Product Folder Sample & Buy Support & Community Tools & Software Technical Documents LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 LPV521 NanoPower, 1.8-V, RRIO, CMOS Input, Operational Amplifier 1 Features 3 Description * The LPV521 is a single nanopower 552-nW amplifier designed for ultra long life battery applications. The operating voltage range of 1.6 V to 5.5 V coupled with typically 351 nA of supply current make it well suited for RFID readers and remote sensor nanopower applications. The device has input common mode voltage 0.1 V over the rails, guaranteed TCVOS and voltage swing to the rail output performance. The LPV521 has a carefully designed CMOS input stage that outperforms competitors with typically 40 fA IBIAS currents. This low input current significantly reduces IBIAS and IOS errors introduced in megohm resistance, high impedance photodiode, and charge sense situations. The LPV521 is a member of the PowerWiseTM family and has an exceptional power-to-performance ratio. 1 For VS = 5 V, Typical Unless Otherwise Noted - Supply Current at VCM = 0.3 V 400 nA (Max) - Operating Voltage Range 1.6 V to 5.5 V - Low TCVOS 3.5 V/C (Max) - VOS 1 mV (Max) - Input Bias Current 40 fA - PSRR 109 dB - CMRR 102 dB - Open-Loop Gain 132 dB - Gain Bandwidth Product 6.2 kHz - Slew Rate 2.4 V/ms - Input Voltage Noise at f = 100 Hz 255 nV/Hz - Temperature Range -40C to 125C The wide input common mode voltage range, guaranteed 1 mV VOS and 3.5 V/C TCVOS enables accurate and stable measurement for both high-side and low-side current sensing. 2 Applications * * * * * * * * Wireless Remote Sensors Powerline Monitoring Power Meters Battery Powered Industrial Sensors Micropower Oxygen sensor and Gas Sensor Active RFID Readers Zigbee Based Sensors for HVAC Control Sensor Network Powered by Energy Scavenging EMI protection was designed into the device to reduce sensitivity to unwanted RF signals from cell phones or other RFID readers. The LPV521 is offered in the 5-pin SC70 package. Device Information(1) PART NUMBER LPV521 PACKAGE BODY SIZE (NOM) SC70 (5) 2.00 mm x 1.25 mm (1) For all available packages, see the orderable addendum at the end of the datasheet. Nanopower Supply Current SUPPLY CURRENT (nA) 125C 800 700 600 500 400 300 200 100 0 85C 25C -40C VCM = VS 0.3V 1 2 3 4 5 6 SUPPLY VOLTAGE (V) 1 An IMPORTANT NOTICE at the end of this data sheet addresses availability, warranty, changes, use in safety-critical applications, intellectual property matters and other important disclaimers. PRODUCTION DATA. LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Table of Contents 1 2 3 4 5 6 7 Features .................................................................. Applications ........................................................... Description ............................................................. Revision History..................................................... Pin Configuration and Functions ......................... Specifications......................................................... 1 1 1 2 3 3 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 6.9 6.10 6.11 3 3 4 4 4 5 6 7 7 8 9 Absolute Maximum Ratings ...................................... ESD Ratings.............................................................. Recommended Operating Conditions....................... Thermal Information .................................................. 1.8-V DC Electrical Characteristics........................... 1.8-V AC Electrical Characteristics ........................... 3.3-V DC Electrical Characteristics........................... 3.3-V AC Electrical Characteristics ........................... 5-V DC Electrical Characteristics.............................. 5-V AC Electrical Characteristics ............................ Typical Characteristics ............................................ Detailed Description ............................................ 19 7.1 7.2 7.3 7.4 8 Overview ................................................................. Functional Block Diagram ....................................... Feature Description................................................. Device Functional Modes........................................ 19 19 19 19 Applications and Implementation ...................... 20 8.1 Application Information............................................ 20 8.2 Typical Applications ................................................ 21 9 Power Supply Recommendations...................... 25 10 Layout................................................................... 26 10.1 Layout Guidelines ................................................. 26 10.2 Layout Example .................................................... 26 11 Device and Documentation Support ................. 27 11.1 11.2 11.3 11.4 11.5 Device Support .................................................... Documentation Support ........................................ Trademarks ........................................................... Electrostatic Discharge Caution ............................ Glossary ................................................................ 27 27 27 27 27 12 Mechanical, Packaging, and Orderable Information ........................................................... 27 4 Revision History NOTE: Page numbers for previous revisions may differ from page numbers in the current version. Changes from Revision C (Feburary 2013) to Revision D * 2 Page Added Pin Configuration and Functions section, ESD Ratings table, Feature Description section, Device Functional Modes, Application and Implementation section, Power Supply Recommendations section, Layout section, Device and Documentation Support section, and Mechanical, Packaging, and Orderable Information section .............................. 1 Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 5 Pin Configuration and Functions SC70-5 Top View 1 5 OUT V - + V 2 + - 3 4 IN- IN+ Pin Functions PIN TYPE DESCRIPTION NO. NAME 1 OUT O Output 2 V- P Negative Power Supply 3 IN+ I Noninverting Input 4 IN- I Inverting Input 5 V+ P Positive Power Supply 6 Specifications 6.1 Absolute Maximum Ratings (1) MIN MAX UNIT -0.3 6 V V- - 0.3 V V+ + 0.3 V V 40 mA Differential Input Voltage (VIN+ - VIN-) -300 300 mV Junction Temperature (2) -40 150 C 260 C 260 C 150 C Any pin relative to VIN+, IN-, OUT Pins + - V , V , OUT Pins Mounting Temperature Infrared or Convection (30 sec.) Wave Soldering Lead Temp. (4 sec.) -65 Storage temperature, Tstg (1) (2) Absolute Maximum Ratings indicate limits beyond which damage may occur. Recommended Operating Conditions indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and test conditions, see the Electrical Characteristics. The maximum power dissipation is a function of TJ(MAX), JA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/ JA. All numbers apply for packages soldered directly onto a PC Board. 6.2 ESD Ratings VALUE Human-body model (HBM), per ANSI/ESDA/JEDEC JS-001 V(ESD) (1) (2) Electrostatic discharge (1) UNIT 2000 Charged-device model (CDM), per JEDEC specification JESD22C101 (2) 1000 Machine Model 200 V JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process. JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 3 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com 6.3 Recommended Operating Conditions (1) MIN MAX UNIT Temperature Range (2) -40 125 C Supply Voltage (VS = V+ - V-) 1.6 5.5 V (1) (2) Absolute Maximum Ratings indicate limits beyond which damage may occur. Recommended Operating Conditions indicate conditions for which the device is intended to be functional, but specific performance is not guaranteed. For guaranteed specifications and test conditions, see Electrical Characteristics. The maximum power dissipation is a function of TJ(MAX), JA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/ JA. All numbers apply for packages soldered directly onto a PC Board. 6.4 Thermal Information DCK THERMAL METRIC (1) RJA (1) (2) Junction-to-ambient thermal resistance UNIT 5 PINS (2) 456 C/W For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953. The maximum power dissipation is a function of TJ(MAX), JA. The maximum allowable power dissipation at any ambient temperature is PD = (TJ(MAX) - TA)/ JA. All numbers apply for packages soldered directly onto a PC Board. 6.5 1.8-V DC Electrical Characteristics Unless otherwise specified, all limits for TA = 25C, V+ = 1.8 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. (1) PARAMETER VOS Input Offset Voltage TEST CONDITIONS VCM = 0.3 V Temperature extremes VCM = 1.5 V TCVOS IBIAS Input Offset Voltage Drift -1 0.1 -1.23 -1 Temperature extremes -1.23 Temperature extremes -3 Input Offset Current CMRR Common Mode Rejection Ratio Power Supply Rejection Ratio Common Mode Voltage Range 0.1 -1 (1) (2) 4 Large Signal Voltage Gain 1 3 0.01 1 50 10 66 Temperature extremes 60 0 V VCM 0.7 V 75 Temperature extremes 74 1.2 V VCM 1.8 V 75 Temperature extremes 53 1.6 V V+ 5.5 V VCM = 0.3 V 85 Temperature extremes 76 CMRR 67 dB CMRR 60 dB mV 1.23 -50 0 V VCM 1.8 V UNIT 1 1.23 V/C pA fA 92 101 dB 120 dB 109 0 0 V 1.8 Temperature extremes AVOL MAX 0.4 Input Bias Current IOS CMVR TYP (2) Temperature extremes PSRR MIN 1.8 VO = 0.5 V to 1.3 V RL = 100 k to V+/2 74 Temperature extremes 73 125 dB Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. The offset voltage average drift is determined by dividing the change in VOS at the temperature extremes by the total temperature change. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 1.8-V DC Electrical Characteristics (continued) Unless otherwise specified, all limits for TA = 25C, V+ = 1.8 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M.(1) PARAMETER VO Output Swing High TEST CONDITIONS MIN + RL = 100 k to V /2 VIN(diff) = 100 mV TYP MAX 2 50 Temperature extremes Output Swing Low 50 RL = 100 k to V+/2 VIN(diff) = -100 mV 2 Temperature extremes Sourcing, VO to V- VIN(diff) = 100 mV IO Output Current (3) Sinking, VO to V+ VIN(diff) = -100 mV Supply Current 3 0.5 1 Temperature extremes IS mA 3 0.5 VCM = 0.3 V 345 Temperature extremes 400 580 VCM = 1.5 V 472 Temperature extremes (3) mV from either rail 50 1 Temperature extremes 50 UNIT nA 600 850 The short circuit test is a momentary open-loop test. 6.6 1.8-V AC Electrical Characteristics Unless otherwise specified, all limits for TA = 25C, V+ = 1.8 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. (1) PARAMETER TEST CONDITIONS MIN TYP GBW Gain-Bandwidth Product CL = 20 pF, RL = 100 k 6.1 SR Slew Rate AV = +1, VIN = 0V to 1.8V Falling Edge 2.9 Rising Edge 2.3 MAX UNIT kHz V/ms m Phase Margin CL = 20 pF, RL = 100 k 72 deg Gm Gain Margin CL = 20 pF, RL = 100 k 19 dB en Input-Referred Voltage Noise Density f = 100 Hz 265 nV/Hz Input-Referred Voltage Noise 0.1 Hz to 10 Hz Input-Referred Current Noise f = 100 Hz In (1) 24 VPP 100 fA/Hz Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 5 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com 6.7 3.3-V DC Electrical Characteristics Unless otherwise specified, all limits for TA = 25C, V+ = 3.3 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. (1) PARAMETER VOS Input Offset Voltage TEST CONDITIONS VCM = 0.3 V Temperature extremes VCM = 3 V TCVOS IBIAS Input Offset Voltage Drift Input Offset Current CMRR Common Mode Rejection Ratio VO 0.1 -1 -1.23 Temperature extremes -3 Power Supply Rejection Ratio Common Mode Voltage Range Large Signal Voltage Gain Output Swing High 0.1 -1 3 0.01 IS Output Current (3) Supply Current 20 72 Temperature extremes 70 0 V VCM 2.2 V 78 Temperature extremes 75 2.7 V VCM 3.3 V 77 Temperature extremes 76 1.6 V V+ 5.5 V VCM = 0.3 V 85 Temperature extremes 76 CMRR 72 dB CMRR 70 dB 106 121 109 dB 0 3.3 Temperature extremes 76 RL = 100 k to V+/2 VIN(diff) = 100 mV dB Temperature extremes 4 Sinking, VO to V+ VIN(diff) = -100 mV 5 Temperature extremes 4 Temperature extremes (2) (3) 6 50 mV from either rail 50 5 VCM = 3 V 50 50 2 Sourcing, VO to V- VIN(diff) = 100 mV VCM = 0.3 V V 120 3 RL = 100 k to V+/2 VIN(diff) = -100 mV pA dB 3.4 82 V/C fA -0.1 VO = 0.5 V to 2.8 V RL = 100 k to V+/2 mV 97 11 mA 12 346 Temperature extremes (1) 1 50 Temperature extremes IO 1 1.23 -50 0 V VCM 3.3 V UNIT 1 1.23 Temperature extremes Output Swing Low MAX 0.4 Temperature extremes AVOL -1 -1.23 Temperature extremes Input Bias Current IOS CMVR TYP (2) Temperature extremes PSRR MIN 400 600 471 600 nA 860 Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. The offset voltage average drift is determined by dividing the change in VOS at the temperature extremes by the total temperature change. The short circuit test is a momentary open-loop test. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 6.8 3.3-V AC Electrical Characteristics Unless otherwise is specified, all limits for TA = 25C, V+ = 3.3 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. (1) PARAMETER TEST CONDITIONS MIN TYP GBW Gain-Bandwidth Product CL = 20 pF, RL = 100 k 6.2 SR Slew Rate AV = +1, VIN = 0V to 3.3V Falling Edge 2.9 Rising Edge 2.5 m Phase Margin CL = 20 pF, RL = 10 k Gm Gain Margin CL = 20 pF, RL = 10 k en Input-Referred Voltage Noise Density f = 100 Hz Input-Referred Voltage Noise 0.1 Hz to 10 Hz Input-Referred Current Noise f = 100 Hz In (1) MAX UNIT kHz V/ms 73 deg 19 dB 259 nV/Hz 22 VPP 100 fA/Hz Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. 6.9 5-V DC Electrical Characteristics Unless otherwise specified, all limits for TA = 25C, V+ = 5 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. (1) PARAMETER VOS Input Offset Voltage TEST CONDITIONS MIN VCM = 0.3 V Temperature extremes IBIAS Input Offset Voltage Drift Temperature extremes -1.23 Temperature extremes -3.5 Common Mode Rejection Ratio CMVR Power Supply Rejection Ratio Common Mode Voltage Range (1) (2) Large Signal Voltage Gain V/C 1 50 60 0 V VCM 5.0 V 75 Temperature extremes 74 0 V VCM 3.9 V 84 Temperature extremes 80 Temperature extremes 76 1.6 V V+ 5.5 V VCM = 0.3 V 85 Temperature extremes 76 CMRR 75 dB CMRR 74 dB Temperature extremes AVOL mV 3.5 -50 77 PSRR 1 UNIT 1.23 0.04 Temperature extremes Input Offset Current 1.23 0.4 Input Bias Current CMRR 1 0.1 (2) IOS MAX 0.1 -1.23 VCM = 4.7 V TCVOS TYP pA fA 102 108 dB 115 109 dB -0.1 5.1 0 5 V VO = 0.5 V to 4.5 V RL = 100 k to V+/2 84 Temperature extremes 76 132 dB Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. The offset voltage average drift is determined by dividing the change in VOS at the temperature extremes by the total temperature change. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 7 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com 5-V DC Electrical Characteristics (continued) Unless otherwise specified, all limits for TA = 25C, V+ = 5 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M.(1) PARAMETER VO Output Swing High TEST CONDITIONS MIN + RL = 100 k to V /2 VIN(diff) = 100 mV TYP MAX 3 50 Temperature extremes Output Swing Low 50 RL = 100 k to V+/2 VIN (diff) = -100 mV 3 Temperature extremes IO Output Current Sourcing, VO to V- VIN(diff) = 100 mV Sinking, VO to V+ VIN(diff) = -100 mV Supply Current 23 8 15 Temperature extremes IS mV from either rail 50 15 Temperature extremes 50 UNIT mA 22 8 VCM = 0.3 V 351 Temperature extremes 400 620 VCM = 4.7 V 475 Temperature extremes 600 nA 870 6.10 5-V AC Electrical Characteristics (1) Unless otherwise specified, all limits for TA = 25C, V+ = 5 V, V- = 0 V, VCM = VO = V+/2, and RL > 1 M. PARAMETER TEST CONDITIONS GBW Gain-Bandwidth Product CL = 20 pF, RL = 100 k SR Slew Rate AV = +1, VIN = 0 V to 5 V MIN (2) TYP (3) 6.2 Falling Edge 1.1 Temperature extremes 1.2 Rising Edge 1.1 Temperature extremes 1.2 MAX (2) UNIT kHz 2.7 2.4 V/ms m Phase Margin CL = 20 pF, RL = 100 k 73 deg Gm Gain Margin CL = 20 pF, RL = 100 k 20 dB en Input-Referred Voltage Noise Density f = 100 Hz 255 nV/Hz Input-Referred Voltage Noise 0.1 Hz to 10 Hz In Input-Referred Current Noise EMIRR EMI Rejection Ratio, IN+ and IN- (4) (1) (2) (3) (4) 8 22 VPP f = 100 Hz 100 fA/Hz VRF_PEAK = 100 mVP (-20 dBP), f = 400 MHz 121 VRF_PEAK = 100 mVP (-20 dBP), f = 900 MHz 121 VRF_PEAK = 100 mVP (-20 dBP), f = 1800 MHz 124 VRF_PEAK = 100 mVP (-20 dBP), f = 2400 MHz 142 dB Electrical Characteristics values apply only for factory testing conditions at the temperature indicated. Factory testing conditions result in very limited self-heating of the device such that TJ = TA. No guarantee of parametric performance is indicated in the electrical tables under conditions of internal self-heating where TJ TA. Absolute Maximum Ratings indicate junction temperature limits beyond which the device may be permanently degraded, either mechanically or electrically. All limits are guaranteed by testing, statistical analysis or design. Typical values represent the most likely parametric norm at the time of characterization. Actual typical values may vary over time and will also depend on the application and configuration. The typical values are not tested and are not guaranteed on shipped production material. The EMI Rejection Ratio is defined as EMIRR = 20log (VRF_PEAK/VOS). Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 6.11 Typical Characteristics At TJ = 25C, unless otherwise specified. 800 700 600 500 400 300 200 100 0 SUPPLY CURRENT (nA) SUPPLY CURRENT (nA) 125C 125C 85C 25C VCM = 0.3V -40C 1 2 3 4 5 800 700 600 500 400 300 200 100 0 6 85C 25C -40C VCM = VS 0.3V 1 2 SUPPLY VOLTAGE (V) 3 4 Figure 1. Supply Current vs. Supply Voltage Figure 2. Supply Current vs. Supply Voltage VS = 1.8V VS = 1.8V -40oC = TA = 125oC o TA = 25 C 25 VCM = VS/2 VCM = VS/2 PERCENTAGE (%) PERCENTAGE (%) 20 15 10 5 20 15 10 5 0 -3.0 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 -2.0 VOS (mV) -1.0 0.0 1.0 2.0 3.0 TCVOS (PV/C) Figure 3. Offset Voltage Distribution Figure 4. TcvOS Distribution 30 20 VS = 3.3V 18 VS = 3.3V 16 TA = 25oC VCM = VS/2 14 12 10 8 6 -40oC d TA d 125oC 25 PERCENTAGE (%) PERCENTAGE (%) 6 30 25 0 5 SUPPLY VOLTAGE (V) VCM = VS/2 20 15 10 4 5 2 0 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 0 -3.0 VOS (mV) -2.0 -1.0 0.0 1.0 2.0 3.0 TCVOS (PV/C) Figure 5. Offset Voltage Distribution Figure 6. TcvOS Distribution Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 9 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 30 25 VS = 5V VS = 5V 15 10 PERCENTAGE (%) PERCENTAGE (%) VCM = VS/2 VCM = VS/2 20 15 10 5 0 -40oC d TA d 125oC 25 TA = 25oC 20 5 0 -3.0 -1.0 -0.8 -0.6 -0.4 -0.2 0.0 0.2 0.4 0.6 0.8 1.0 -2.0 -1.0 VOS (mV) Figure 7. Offset Voltage Distribution -40C 100 0 -100 -300 3.0 100 25C -200 2.0 VS = 3.3V -40C 150 VOS (eV) VOS (eV) 200 1.0 Figure 8. TcvOS Distribution VS = 1.8V 300 0.0 TCVOS (PV/C) 50 25C 0 -50 -100 85C 125C 85C -150 125C 0.0 0.3 0.6 0.9 1.2 1.5 1.8 -0.1 0.4 0.9 Figure 9. Input Offset Voltage vs. Input Common Mode VS = 5V 100 50 50 25C 0 -50 2.9 3.4 25C 0 -50 -100 85C -150 85C -150 125C 125C -0.50.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 1 2 3 4 5 6 VS (V) VCM (V) Figure 11. Input Offset Voltage vs. Input Common Mode 10 2.4 VCM = 0.3V -40C 150 -40C 100 -100 1.9 Figure 10. Input Offset Voltage vs. Input Common Mode VOS (eV) VOS (eV) 150 1.4 VCM (V) VCM (V) Figure 12. Input Offset Voltage vs. Supply Voltage Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 100 50 50 VOS (eV) 100 0 85C -50 25C 0 -50 85C 125C -100 VS = 1.8V 150 -40C 25C VOS (eV) -40C VCM = VS - 0.3V 150 -100 -150 -150 125C 1 2 3 4 5 0.0 6 0.5 VS (V) Figure 13. Input Offset Voltage vs. Supply Voltage 150 150 0 -50 85C -100 VS = 5V -40C 50 25C 0 -50 85C -100 -150 -150 125C 0.0 0.5 1.0 1.5 125C 2.0 2.5 3.0 3.5 0.0 1.0 Figure 15. Input Offset Voltage vs. Output Voltage 150 0 -50 4.0 5.0 VS = 3.3V -40C 100 25C VOS (eV) VOS (eV) 100 50 3.0 Figure 16. Input Offset Voltage vs. Output Voltage VS = 1.8V -40C 2.0 VOUT (V) VOUT (V) 150 2.0 100 25C VOS (eV) VOS (eV) 100 50 1.5 Figure 14. Input Offset Voltage vs. Output Voltage VS = 3.3V -40C 1.0 VOUT (V) 85C -100 50 25C 0 -50 85C -100 -150 -150 125C 125C 0.0 0.5 1.0 1.5 2.0 0.0 0.5 1.0 1.5 2.0 ISOURCE (mA) ISOURCE (mA) Figure 17. Input Offset Voltage vs. Sourcing Current Figure 18. Input Offset Voltage vs. Sourcing Current Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 11 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. VS = 5V -40C 150 100 VS = 1.8V -40C 150 100 25C VOS (eV) VOS (eV) 25C 50 0 -50 -100 50 0 -50 85C -100 85C -150 -150 125C 125C 0.0 0.5 1.0 1.5 2.0 0.0 0.5 Figure 19. Input Offset Voltage vs. Sourcing Current 2.0 VS = 5V -40C 150 100 100 25C VOS (eV) 50 VOS (eV) 1.5 Figure 20. Input Offset Voltage vs. Sinking Current VS = 3.3V -40C 150 1.0 ISOURCE (mA) ISOURCE (mA) 0 -50 85C -100 25C 50 0 -50 -100 -150 85C -150 125C 0.0 0.5 1.0 125C 1.5 2.0 0.0 0.5 ISOURCE (mA) 1.0 1.5 2.0 ISOURCE (mA) Figure 21. Input Offset Voltage vs. Sinking Current Figure 22. Input Offset Voltage vs. Sinking Current 5 5 VS = 1.8V VS = 1.8V -40C 4 -40C 4 ISINK (mA) ISOURCE (mA) 25C 25C 3 2 3 2 85C 85C 1 1 125C 0 0.0 0.5 1.0 1.5 2.0 0 0.0 OUTPUT VOLTAGE REFERENCED TO V (V) 12 0.5 1.0 1.5 2.0 OUTPUT VOLTAGE REFERENCED TO V- (V) + Figure 23. Sourcing Current vs. Output Voltage 125C Figure 24. Sinking Current vs. Output Voltage Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 16 16 VS = 3.3V 12 25C ISINK (mA) ISOURCE (mA) 12 8 85C 4 25C 8 85C 4 125C 125C 0 0.0 0.5 1.0 1.5 2.0 2.5 3.0 0 0.0 3.5 0.5 1.0 1.5 2.0 2.5 3.0 3.5 - + OUTPUT VOLTAGE REFERENCED TO V (V) OUTPUT VOLTAGE REFERENCED TO V (V) Figure 25. Sourcing Current vs. Output Voltage Figure 26. Sinking Current vs. Output Voltage 30 30 VS = 5V -40C VS = 5V -40C 25 25 25C 25C 20 20 ISINK (mA) ISOURCE (mA) -40C VS = 3.3V -40C 15 10 15 85C 10 85C 125C 5 0 0 5 125C 1 2 3 4 0 0 5 OUTPUT VOLTAGE REFERENCED TO V+ (V) 2 3 4 5 - OUTPUT VOLTAGE REFERENCED TO V (V) Figure 27. Sourcing Current vs. Output Voltage Figure 28. Sinking Current vs. Output Voltage 40 40 VCM = VS/2 VCM = VS/2 -40C 30 30 -40C ISINK (mA) ISOURCE (mA) 1 25C 20 10 25C 20 10 85C 85C 125C 0 1 2 3 4 125C 5 6 0 1 VS (V) 2 3 4 5 6 VS (V) Figure 29. Sourcing Current vs. Supply Voltage Figure 30. Sinking Current vs. Supply Voltage Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 13 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 5 125C 4 VOUT FROM RAIL (mV) VOUT FROM RAIL (mV) 5 RL = 100 k: 85C 3 2 25C 1 RL = 100 k: 125C 4 85C 3 -40C 0 1 -40C 3 2 2 4 5 25C 6 1 2 3 4 Figure 31. Output Swing High vs. Supply Voltage 15 VS = 1.8V VS = 1.8V 10 10 5 125C 5 25C IBIAS (pA) IBIAS (fA) 6 Figure 32. Output Swing Low vs. Supply Voltage 15 0 -5 5 VS (V) VS (V) 0 -5 -40C -10 85C -10 -15 0.0 0.5 1.0 1.5 -15 0.0 2.0 0.5 1.0 1.5 2.0 VCM (V) VCM (V) Figure 33. Input Bias Current vs. Common Mode Voltage Figure 34. Input Bias Current vs. Common Mode Voltage 50 15 VS = 3.3V 40 VS = 3.3V 10 30 25C 10 0 -10 -20 125C 5 IBIAS (pA) IBIAS (fA) 20 0 -5 85C -40C -10 -30 -40 0.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 -15 0.0 1.0 1.5 2.0 2.5 3.0 3.5 VCM (V) VCM (V) Figure 35. Input Bias Current vs. Common Mode Voltage 14 0.5 Figure 36. Input Bias Current vs. Common Mode Voltage Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 400 30 VS = 5V VS = 5V 25 300 20 200 15 IBIAS (pA) IBIAS (fA) 25C 100 0 125C 10 5 0 -5 -100 85C -40C -10 -200 -15 -300 0 1 2 3 4 -20 0 5 1 2 VCM (V) 3 4 5 VCM (V) Figure 37. Input Bias Current vs. Common Mode Voltage Figure 38. Input Bias Current vs. Common Mode Voltage 100 VS = 5V VS = 5V VS = 1.8V, 3.3V, 5V VS = 1.8V, 3.3V, 5V 100 90 80 VS = 3.3V CMRR (dB) PSRR (dB) 80 60 VS = 1.8V +PSRR 40 VS = 1.8V 70 60 20 -PSRR 50 0 100 1k 10k 40 10 1e1 100k 100 1e2 FREQUENCY (Hz) 130 110 90 70 25C 50 30 10 -40C -10 -30 0 -20 100 GAIN (dB) 125C 130 110 90 70 25C 50 30 10 -40C -10 -30 RL = 1 M: 40 PHASE () GAIN (dB) GAIN CL = 20 pF PHASE RL = 1 M: 85C 20 VS = 3.3V 60 CL = 20 pF 40 100k 1e5 Figure 40. CMRR vs. Frequency VS = 1.8V PHASE 10k 1e4 FREQUENCY (Hz) Figure 39. PSRR vs. Frequency 60 1k 1e3 85C 20 GAIN 125C 0 PHASE () 10 -20 1k 10k 100k 100 FREQUENCY (Hz) 1k 10k 100k FREQUENCY (Hz) Figure 41. Frequency Response vs. Temperature Figure 42. Frequency Response vs. Temperature Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 15 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. 130 110 90 70 25C 50 30 10 -40C -10 -30 125C 0 20 GAIN 0 -20 RL = 10 k: -20 100 1k 10k 100k 100 1k Figure 43. Frequency Response vs. Temperature GAIN 0 40 GAIN (dB) 20 100 20 GAIN 0 RL = 10 k: -20 10k 100k 100 1k FREQUENCY (Hz) 20 GAIN CL = 200 pF 0 -20 40 CL = 100 pF 20 GAIN CL = 200 pF 0 130 110 CL = 20 pF 90 70 50 30 10 -10 -30 -20 100 1k 10k 100k FREQUENCY (Hz) 100 1k 10k 100k FREQUENCY (Hz) Figure 47. Frequency Response vs. CL 16 RL = 10 M: CL = 50 pF PHASE GAIN (dB) CL = 100 pF 130 110 CL = 20 pF 90 70 50 30 10 -10 -30 PHASE () GAIN (dB) 40 VS = 3.3V 60 RL = 10 M: CL = 50 pF 100k Figure 46. Frequency Response vs. RL VS = 1.8V PHASE 10k FREQUENCY (Hz) Figure 45. Frequency Response vs. RL 60 130 110 RL = 10 M: 90 70 50 30 10 -10 -30 RL = 10 k: -20 1k CL = 20 pF RL = 1 M: PHASE PHASE () GAIN (dB) 40 130 110 RL = 10 M: 90 70 50 30 10 -10 -30 VS = 5V RL = 100 k: 60 CL = 20 pF RL = 1 M: PHASE 100k Figure 44. Frequency Response vs. RL VS = 3.3V RL = 100 k: 10k FREQUENCY (Hz) FREQUENCY (Hz) 60 130 110 RL = 10 M: 90 70 50 30 10 -10 -30 PHASE () GAIN GAIN (dB) 85C 20 40 PHASE () GAIN (dB) 40 CL = 20 pF RL = 1 M: PHASE RL = 1 M: PHASE () PHASE VS = 1.8V RL = 100 k: 60 CL = 20 pF PHASE () VS = 5V 60 Submit Documentation Feedback Figure 48. Frequency Response vs. CL Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. VS = 5V 60 GAIN CL = 200 pF 0 FALLING EDGE 3.0 SLEW RATE (V/ms) GAIN (dB) CL = 100 pF PHASE () 130 110 CL = 20 pF 90 70 50 30 10 -10 -30 40 20 3.3 RL = 10 M: CL = 50 pF PHASE 2.7 2.4 RISING EDGE 2.1 AV = +1 1.8 -20 VOUT = VS 100 1k 10k 100k 1.5 FREQUENCY (Hz) 2.3 3.1 3.9 4.7 5.5 SUPPLY VOLTAGE (V) Figure 49. Frequency Response vs. CL Figure 50. Slew Rate vs. Supply Voltage 15 1000 VS = 1.8V VCM = VS/2 VOLTAGE NOISE (nV/iHz) 10 5 PV/DIV 5 0 -5 -10 VS = 5V 100 1 10 100 1k -15 -2.5 -1.5 -0.5 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 10k FREQUENCY (Hz) 1s/DIV Figure 52. 0.1 to 10 Hz Time Domain Voltage Noise 15 10 10 5 5 5 PV/DIV 5 PV/DIV Figure 51. Voltage Noise vs. Frequency 15 0 -5 VS = 5V VCM = VS/2 0 -5 -10 -10 VS = 3.3V VCM = VS/2 -15 -2.5 -1.5 -0.5 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 -15 -2.5 -1.5 -0.5 0.5 1.5 2.5 3.5 4.5 5.5 6.5 7.5 1s/DIV 1s/DIV Figure 53. 0.1 to 10 Hz Time Domain Voltage Noise Figure 54. 0.1 to 10 Hz Time Domain Voltage Noise Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 17 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Characteristics (continued) At TJ = 25C, unless otherwise specified. INPUT 50 mV/DIV 50 mV/DIV INPUT OUTPUT OUTPUT VS = 5V VS = 1.8V RL = 100 k: RL = 100 k: 200 Ps/DIV 200 Ps/DIV Figure 55. Small Signal Pulse Response Figure 56. Small Signal Pulse Response INPUT 500 mV/DIV 500 mV/DIV INPUT OUTPUT OUTPUT VS = 5V VS = 1.8V RL = 100 k: RL = 100 k: 200 Ps/DIV 200 Ps/DIV Figure 57. Large Signal Pulse Response Figure 58. Large Signal Pulse Response 4 INPUT 3 OUTPUT EMIRRV_PEAK (dB) 2 1V/DIV 1 0 -1 -2 + -3 170 150 130 110 90 70 50 30 10 VS = 5V V = +2.5V VPEAK = -20 dBVp - V = -2.5V -4 2 ms/DIV 0.1 1.0e-1 1 1.0 10 1.0e1 100 1.0e2 1000 1.0e3 10000 1.0e4 FREQUENCY (MHz) Figure 59. Overload Recovery Waveform 18 Submit Documentation Feedback Figure 60. EMIRR vs. Frequency Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 7 Detailed Description 7.1 Overview The LPV521 is fabricated with Texas Instruments' state-of-the-art VIP50 process. This proprietary process dramatically improves the performance of Texas Instruments' low-power and low-voltage operational amplifiers. The following sections showcase the advantages of the VIP50 process and highlight circuits which enable ultralow power consumption. 7.2 Functional Block Diagram Figure 61. Block Diagram 7.3 Feature Description The amplifier's differential inputs consist of a noninverting input (+IN) and an inverting input (-IN). The amplifier amplifies only the difference in voltage between the two inputs, which is called the differential input voltage. The output voltage of the op-amp Vout is given by Equation 1: VOUT = AOL (IN+ - IN-) (1) where AOL is the open-loop gain of the amplifier, typically around 100 dB (100,000x, or 10uV per Volt). 7.4 Device Functional Modes 7.4.1 Input Stage The LPV521 has a rail-to-rail input which provides more flexibility for the system designer. Rail-to-rail input is achieved by using in parallel, one PMOS differential pair and one NMOS differential pair. When the common mode input voltage (VCM) is near V+, the NMOS pair is on and the PMOS pair is off. When VCM is near V-, the NMOS pair is off and the PMOS pair is on. When VCM is between V+ and V-, internal logic decides how much current each differential pair will get. This special logic ensures stable and low distortion amplifier operation within the entire common mode voltage range. Because both input stages have their own offset voltage (VOS) characteristic, the offset voltage of the LPV521 becomes a function of VCM. VOS has a crossover point at 1.0 V below V+. Refer to the 'VOS vs. VCM' curve in the Typical Performance Characteristics section. Caution should be taken in situations where the input signal amplitude is comparable to the VOS value and/or the design requires high accuracy. In these situations, it is necessary for the input signal to avoid the crossover point. In addition, parameters such as PSRR and CMRR which involve the input offset voltage will also be affected by changes in VCM across the differential pair transition region. 7.4.2 Output Stage The LPV521 output voltage swings 3 mV from rails at 3.3-V supply, which provides the maximum possible dynamic range at the output. This is particularly important when operating on low supply voltages. The LPV521 Maximum Output Voltage Swing defines the maximum swing possible under a particular output load. The LPV521 output swings 50 mV from the rail at 5-V supply with an output load of 100 k. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 19 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com 8 Applications and Implementation NOTE Information in the following applications sections is not part of the TI component specification, and TI does not warrant its accuracy or completeness. TI's customers are responsible for determining suitability of components for their purposes. Customers should validate and test their design implementation to confirm system functionality. 8.1 Application Information The LPV521is specified for operation from 1.6 V to 5.5 V (0.8 V to 2.25 V). Many of the specifications apply from -40C to 125C. The LMV521 features rail to rail input and rail-to-rail output swings while consuming only nanowatts of power. Parameters that can exhibit significant variance with regard to operating voltage or temperature are presented in the Typical Characteristics section. 8.1.1 Driving Capacitive Load The LPV521 is internally compensated for stable unity gain operation, with a 6.2-kHz, typical gain bandwidth. However, the unity gain follower is the most sensitive configuration to capacitive load. The combination of a capacitive load placed at the output of an amplifier along with the amplifier's output impedance creates a phase lag, which reduces the phase margin of the amplifier. If the phase margin is significantly reduced, the response will be under damped which causes peaking in the transfer and, when there is too much peaking, the op amp might start oscillating. - RISO VOUT VIN + CL Figure 62. Resistive Isolation of Capacitive Load In order to drive heavy capacitive loads, an isolation resistor, RISO, should be used, as shown in Figure 62. By using this isolation resistor, the capacitive load is isolated from the amplifier's output. The larger the value of RISO, the more stable the amplifier will be. If the value of RISO is sufficiently large, the feedback loop will be stable, independent of the value of CL. However, larger values of RISO result in reduced output swing and reduced output current drive. Recommended minimum values for RISO are given in the following table, for 5-V supply. Figure 63 shows the typical response obtained with the CL = 50 pF and RISO = 154 k. The other values of RISO in the table were chosen to achieve similar dampening at their respective capacitive loads. Notice that for the LPV521 with larger CL a smaller RISO can be used for stability. However, for a given CL a larger RISO will provide a more damped response. For capacitive loads of 20 pF and below no isolation resistor is needed. 20 CL RISO 0 - 20 pF not needed 50 pF 154 k 100 pF 118 k 500 pF 52.3 k 1 nF 33.2 k 5 nF 17.4 k 10 nF 13.3 k Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 VIN 20 mV/DIV VOUT VS = 5V 200 Ps/DIV Figure 63. Step Response 8.1.2 EMI Suppression The near-ubiquity of cellular, Bluetooth, and Wi-Fi signals and the rapid rise of sensing systems incorporating wireless radios make electromagnetic interference (EMI) an evermore important design consideration for precision signal paths. Though RF signals lie outside the op amp band, RF carrier switching can modulate the DC offset of the op amp. Also some common RF modulation schemes can induce down-converted components. The added DC offset and the induced signals are amplified with the signal of interest and thus corrupt the measurement. The LPV521 uses on chip filters to reject these unwanted RF signals at the inputs and power supply pins; thereby preserving the integrity of the precision signal path. Twisted pair cabling and the active front-end's common-mode rejection provide immunity against low-frequency noise (i.e. 60-Hz or 50-Hz mains) but are ineffective against RF interference. Even a few centimeters of PCB trace and wiring for sensors located close to the amplifier can pick up significant 1 GHz RF. The integrated EMI filters of the LPV521 reduce or eliminate external shielding and filtering requirements, thereby increasing system robustness. A larger EMIRR means more rejection of the RF interference. For more information on EMIRR, please refer to AN-1698. 8.2 Typical Applications 8.2.1 60-Hz Twin T-Notch Filter VBATT = 3V o2V @ end of life CR2032 Coin Cell 225 mAh = 5 circuits @ 9.5 yrs. 10 M: 10 M: VBATT - Remote Sensor 10 M: + VIN Signal + 60 Hz To ADC VOUT 10 M: 270 pF 270 pF 10 M: 10 M: Signal x 2 (No 60 Hz) 60 Hz Twin T Notch Filter 270 pF AV = 2 V/V 270 pF Figure 64. 60-Hz Notch Filter Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 21 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Applications (continued) 8.2.1.1 Design Requirements Small signals from transducers in remote and distributed sensing applications commonly suffer strong 60-Hz interference from AC power lines. The circuit of Figure 64 notches out the 60 Hz and provides a gain AV = 2 for the sensor signal represented by a 1-kHz sine wave. Similar stages may be cascaded to remove 2nd and 3rd harmonics of 60 Hz. Thanks to the nA power consumption of the LPV521, even 5 such circuits can run for 9.5 years from a small CR2032 lithium cell. These batteries have a nominal voltage of 3 V and an end of life voltage of 2 V. With an operating voltage from 1.6 V to 5.5 V the LPV521 can function over this voltage range. 8.2.1.2 Detailed Design Procedure The notch frequency is set by F0 = 1 / 2RC. To achieve a 60-Hz notch use R = 10 M and C = 270 pF. If eliminating 50-Hz noise, which is common in European systems, use R = 11.8 M and C = 270 pF. The Twin T Notch Filter works by having two separate paths from VIN to the amplifier's input. A low frequency path through the resistors R - R and another separate high frequency path through the capacitors C - C. However, at frequencies around the notch frequency, the two paths have opposing phase angles and the two signals will tend to cancel at the amplifier's input. To ensure that the target center frequency is achieved and to maximize the notch depth (Q factor) the filter needs to be as balanced as possible. To obtain circuit balance, while overcoming limitations of available standard resistor and capacitor values, use passives in parallel to achieve the 2C and R/2 circuit requirements for the filter components that connect to ground. To make sure passive component values stay as expected clean board with alcohol, rinse with deionized water, and air dry. Make sure board remains in a relatively low humidity environment to minimize moisture which may increase the conductivity of board components. Also large resistors come with considerable parasitic stray capacitance which effects can be reduced by cutting out the ground plane below components of concern. Large resistors are used in the feedback network to minimize battery drain. When designing with large resistors, resistor thermal noise, op amp current noise, as well as op amp voltage noise, must be considered in the noise analysis of the circuit. The noise analysis for the circuit in Figure 64 can be done over a bandwidth of 5 kHz, which takes the conservative approach of overestimating the bandwidth (LPV521 typical GBW/AV is lower). The total noise at the output is approximately 800 Vpp, which is excellent considering the total consumption of the circuit is only 540 nA. The dominant noise terms are op amp voltage noise (550 Vpp), current noise through the feedback network (430 Vpp), and current noise through the notch filter network (280 Vpp). Thus the total circuit's noise is below 1/2 LSB of a 10 bit system with a 2-V reference, which is 1 mV. 8.2.1.3 Application Curve Figure 65. 60-Hz Notch Filter Waveform 22 Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Applications (continued) 8.2.2 Portable Gas Detection Sensor 100 M: V 1 M: + VOUT + - V RL OXYGEN SENSOR Figure 66. Precision Oxygen Sensor 8.2.2.1 Design Requirements Gas sensors are used in many different industrial and medical applications. They generate a current which is proportional to the percentage of a particular gas sensed in an air sample. This current goes through a load resistor and the resulting voltage drop is measured. The LPV521 makes an excellent choice for this application as it only draws 345 nA of current and operates on supply voltages down to 1.6V. Depending on the sensed gas and sensitivity of the sensor, the output current can be in the order of tens of microamperes to a few milliamperes. Gas sensor datasheets often specify a recommended load resistor value or they suggest a range of load resistors to choose from. Oxygen sensors are used when air quality or oxygen delivered to a patient needs to be monitored. Fresh air contains 20.9% oxygen. Air samples containing less than 18% oxygen are considered dangerous. This application detects oxygen in air. Oxygen sensors are also used in industrial applications where the environment must lack oxygen. An example is when food is vacuum packed. There are two main categories of oxygen sensors, those which sense oxygen when it is abundantly present (i.e. in air or near an oxygen tank) and those which detect traces of oxygen in ppm. 8.2.2.2 Detailed Design Procedure Figure 66 shows a typical circuit used to amplify the output of an oxygen detector. The oxygen sensor outputs a known current through the load resistor. This value changes with the amount of oxygen present in the air sample. Oxygen sensors usually recommend a particular load resistor value or specify a range of acceptable values for the load resistor. The use of the nanopower LPV521 means minimal power usage by the op amp and it enhances the battery life. With the components shown in Figure 66 the circuit can consume less than 0.5 A of current ensuring that even batteries used in compact portable electronics, with low mAh charge ratings, could last beyond the life of the oxygen sensor. The precision specifications of the LPV521, such as its very low offset voltage, low TCVOS , low input bias current, high CMRR, and high PSRR are other factors which make the LPV521 a great choice for this application. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 23 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com Typical Applications (continued) 8.2.2.3 Application Curve 5.0 4.5 4.0 VOUT (V) 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0 10 20 30 40 50 VSENSOR (mV) C001 Figure 67. Calculated Oxygen Sensor Circuit Output (Single 5V Supply) 8.2.3 High-Side Battery Current Sensing ICHARGE RSENSE + V - + + V R1 24.9 k: Q1 2N2907 RSENSE X R3 VOUT = R1 - R2 24.9 k: + 10: LOAD X ICHARGE VOUT R3 10 M: Figure 68. High-Side Current Sensing 8.2.3.1 Design Requirements The rail-to-rail common mode input range and the very low quiescent current make the LPV521 ideal to use in high-side and low-side battery current sensing applications. The high-side current sensing circuit in Figure 68 is commonly used in a battery charger to monitor the charging current in order to prevent over charging. A sense resistor RSENSE is connected in series with the battery. 8.2.3.2 Detailed Design Procedure The theoretical output voltage of the circuit is VOUT = [ (R)SENSE x R3) / R1 ] x ICHARGE. In reality, however, due to the finite Current Gain, , of the transistor the current that travels through R3 will not be ICHARGE, but instead, will be x ICHARGE or /( +1) x ICHARGE. A Darlington pair can be used to increase the and performance of the measuring circuit. Using the components shown in Figure 68 will result in VOUT 4000 x ICHARGE. This is ideal to amplify a 1 mA ICHARGE to near full scale of an ADC with VREF at 4.1 V. A resistor, R2 is used at the noninverting input of the amplifier, with the same value as R1 to minimize offset voltage. 24 Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 Typical Applications (continued) Selecting values per Figure 68 will limit the current traveling through the R1 - Q1 - R3 leg of the circuit to under 1 A which is on the same order as the LPV521 supply current. Increasing resistors R1 , R2 , and R3 will decrease the measuring circuit supply current and extend battery life. Decreasing RSENSE will minimize error due to resistor tolerance, however, this will also decrease VSENSE = ICHARGE x RSENSE, and in turn the amplifier offset voltage will have a more significant contribution to the total error of the circuit. With the components shown in Figure 68 the measurement circuit supply current can be kept below 1.5 A and measure 100 A to 1 mA. 8.2.3.3 Application Curve 5.0 4.5 4.0 VOUT (V) 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 0 0.25 0.5 0.75 1 ICHARGE (mA) 1.25 1.5 C001 Figure 69. Calculated High-Side Current Sense Circuit Output 9 Power Supply Recommendations The LPV521 is specified for operation from 1.6 V to 5.5 V (0.8 V to 2.75 V) over a -40C to 125C temperature range. Parameters that can exhibit significant variance with regard to operating voltage or temperature are presented in the Typical Characteristics. CAUTION Supply voltages larger than 6 V can permanently damage the device. Low bandwidth nanopower devices do not have good high frequency (>1KHz) AC PSRR rejection against highfrequency switching supplies and other kHz and above noise sources, so extra supply filtering is recommended if kHz range noise is expected on the power supply lines. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 25 LPV521 SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 www.ti.com 10 Layout 10.1 Layout Guidelines For best operational performance of the device, use good printed circuit board (PCB) layout practices, including: * Noise can propagate into analog circuitry through the power pins of the circuit as a whole and op amp itself. Bypass capacitors are used to reduce the coupled noise by providing low-impedance power sources local to the analog circuitry. * Connect low-ESR, 0.1-F ceramic bypass capacitors between each supply pin and ground, placed as close to the device as possible. A single bypass capacitor from V+ to ground is applicable for singlesupply applications. * Separate grounding for analog and digital portions of circuitry is one of the simplest and most-effective methods of noise suppression. One or more layers on multilayer PCBs are usually devoted to ground planes. A ground plane helps distribute heat and reduces EMI noise pickup. Make sure to physically separate digital and analog grounds paying attention to the flow of the ground current. For more detailed information refer to Circuit Board Layout Techniques, SLOA089. * In order to reduce parasitic coupling, run the input traces as far away from the supply or output traces as possible. If it is not possible to keep them separate, it is much better to cross the sensitive trace perpendicular as opposed to in parallel with the noisy trace. * Place the external components as close to the device as possible. As shown in Layout Example, keeping RF and RG close to the inverting input minimizes parasitic capacitance. * Keep the length of input traces as short as possible. Always remember that the input traces are the most sensitive part of the circuit. * Consider a driven, low-impedance guard ring around the critical traces. A guard ring can significantly reduce leakage currents from nearby traces that are at different potentials. 10.2 Layout Example Figure 70. Noninverting Layout Example 26 Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 LPV521 www.ti.com SNOSB14D - AUGUST 2009 - REVISED DECEMBER 2014 11 Device and Documentation Support 11.1 Device Support 11.1.1 Development Support LPV521 PSPICE Model, SNOM024 TINA-TI SPICE-Based Analog Simulation Program, http://www.ti.com/tool/tina-ti TI Filterpro Software, http://www.ti.com/tool/filterpro DIP Adapter Evaluation Module, http://www.ti.com/tool/dip-adapter-evm TI Universal Operational Amplifier Evaluation Module, http://www.ti.com/tool/opampevm Evaluation board for 5-pin, north-facing amplifiers in the SC70 package, SNOA487. Manual for LMH730268 Evaluation board 551012922-001 11.2 Documentation Support 11.2.1 Related Documentation For related documentation, see the following: * Feedback Plots Define Op Amp AC Performance, SBOA015 (AB-028) * Circuit Board Layout Techniques, SLOA089 * Op Amps for Everyone, SLOD006 * AN-1698 A Specification for EMI Hardened Operational Amplifiers, SNOA497 * EMI Rejection Ratio of Operational Amplifiers, SBOA128 * Capacitive Load Drive Solution using an Isolation Resistor, TIPD128 * Handbook of Operational Amplifier Applications, SBOA092 11.3 Trademarks PowerWise is a trademark of Texas Instruments. All other trademarks are the property of their respective owners. 11.4 Electrostatic Discharge Caution This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with appropriate precautions. Failure to observe proper handling and installation procedures can cause damage. ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more susceptible to damage because very small parametric changes could cause the device not to meet its published specifications. 11.5 Glossary SLYZ022 -- TI Glossary. This glossary lists and explains terms, acronyms, and definitions. 12 Mechanical, Packaging, and Orderable Information The following pages include mechanical, packaging, and orderable information. This information is the most current data available for the designated devices. This data is subject to change without notice and revision of this document. For browser-based versions of this data sheet, refer to the left-hand navigation. Submit Documentation Feedback Copyright (c) 2009-2014, Texas Instruments Incorporated Product Folder Links: LPV521 27 PACKAGE OPTION ADDENDUM www.ti.com 10-Dec-2020 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Pins Package Drawing Qty Eco Plan (2) Lead finish/ Ball material MSL Peak Temp Op Temp (C) Device Marking (3) (4/5) (6) LPV521MG/NOPB ACTIVE SC70 DCK 5 1000 RoHS & Green SN Level-1-260C-UNLIM -40 to 125 AHA LPV521MGE/NOPB ACTIVE SC70 DCK 5 250 RoHS & Green SN Level-1-260C-UNLIM -40 to 125 AHA LPV521MGX/NOPB ACTIVE SC70 DCK 5 3000 RoHS & Green SN Level-1-260C-UNLIM -40 to 125 AHA (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based flame retardants must also meet the <=1000ppm threshold requirement. (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Device Marking for that device. (6) Lead finish/Ball material - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead finish/Ball material values may wrap to two lines if the finish value exceeds the maximum column width. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. 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Addendum-Page 2 PACKAGE MATERIALS INFORMATION www.ti.com 31-Jul-2016 TAPE AND REEL INFORMATION *All dimensions are nominal Device Package Package Pins Type Drawing LPV521MG/NOPB SC70 DCK 5 LPV521MGE/NOPB SC70 DCK LPV521MGX/NOPB SC70 DCK SPQ Reel Reel A0 Diameter Width (mm) (mm) W1 (mm) B0 (mm) K0 (mm) P1 (mm) W Pin1 (mm) Quadrant 1000 178.0 8.4 2.25 2.45 1.2 4.0 8.0 Q3 5 250 178.0 8.4 2.25 2.45 1.2 4.0 8.0 Q3 5 3000 178.0 8.4 2.25 2.45 1.2 4.0 8.0 Q3 Pack Materials-Page 1 PACKAGE MATERIALS INFORMATION www.ti.com 31-Jul-2016 *All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LPV521MG/NOPB SC70 DCK 5 1000 210.0 185.0 35.0 LPV521MGE/NOPB SC70 DCK 5 250 210.0 185.0 35.0 LPV521MGX/NOPB SC70 DCK 5 3000 210.0 185.0 35.0 Pack Materials-Page 2 IMPORTANT NOTICE AND DISCLAIMER TI PROVIDES TECHNICAL AND RELIABILITY DATA (INCLUDING DATASHEETS), DESIGN RESOURCES (INCLUDING REFERENCE DESIGNS), APPLICATION OR OTHER DESIGN ADVICE, WEB TOOLS, SAFETY INFORMATION, AND OTHER RESOURCES "AS IS" AND WITH ALL FAULTS, AND DISCLAIMS ALL WARRANTIES, EXPRESS AND IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT OF THIRD PARTY INTELLECTUAL PROPERTY RIGHTS. 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