ADVANCED LINEAR DEVICES, INC. TM e (R) EPAD D LE AB EN ALD2721E/ALD2721 DUAL EPAD(R) MICROPOWER CMOS OPERATIONAL AMPLIFIER KEY FEATURES BENEFITS * * * * * * * * * * * * * Eliminates manual and elaborate system trimming procedures * Remote controlled automated trimming * In-System Programming capability * No external components * No internal clocking noise source * Simple and cost effective * Small package size * Extremely small total functional volume size * Low system implementation cost * Micropower and Low Voltage EPAD (Electrically Programmable Analog Device) User programmable VOS trimmer Computer-assisted trimming Rail-to-rail input/output Compatible with standard EPAD Programmer Each amplifier VOS can be trimmed to a different VOS level High precision through in-system circuit precision trimming Reduces or eliminates VOS, PSRR, CMRR and TCVOS errors System level "calibration" capability Application Specific Programming mode In-System Programming mode Electrically programmable to compensate for external component tolerances * Achieves 0.01pA input bias current and 35V input offset voltage simultaneously * Low voltage operation GENERAL DESCRIPTION The ALD2721E/ALD2721 is a dual monolithic rail-to-rail precision CMOS operational amplifier with integrated user programmable EPAD (Electrically Programmable Analog Device) based offset voltage adjustment. The ALD2721E/ALD2721 is a dual version of the ALD1721E/ALD2721 operational amplifier. Each ALD2721E/ALD2721 operational amplifier features individual user-programming offset voltage trimming, resulting in significantly enhanced total system performance and user flexibility. EPAD technology is an exclusive ALD design which has been refined for analog applications where precision voltage trimming is necessary to achieve a desired performance. It utilizes CMOS FETs as in-circuit elements for trimming of offset voltage bias characteristics with the aid of a personal computer under software control. Once programmed, the set parameters are stored indefinitely within the device even after power-down. EPAD offers the circuit designer a convenient and cost-effective trimming solution for achieving the very highest amplifier/system performance. The ALD2721E/ALD2721 dual operational amplifier features rail-to-rail input and output voltage ranges, tolerance to over-voltage input spikes of 300mV beyond supply rails, capacitive loading up to 50pF, extremely low input currents of 0.01pA typical, high open loop voltage gain, useful bandwidth of 700KHz, slew rate of 0.7V/s, and low typical supply current of 200A for both amplifiers. ORDERING INFORMATION Operating Temperature Range 0C to +70C 0C to +70C -55C to +125C 14-Pin Small Outline Package (SOIC) 14-Pin Plastic Dip Package 14-Pin CERDIP Package ALD2721ESB ALD2721SB ALD2721EPB ALD2721PB ALD2721EDB ALD2721DB * Contact factory for high temperature versions. APPLICATIONS * * * * * * * * * * * * * * Sensor interface circuits Transducer biasing circuits Capacitive and charge integration circuits Biochemical probe interface Signal conditioning Portable instruments High source impedance electrode amplifiers Precision Sample and Hold amplifiers Precision current to voltage converter Error correction circuits Sensor compensation circuits Precision gain amplifiers Periodic In-system calibration System output level shifter PIN CONFIGURATION -IN A 1 14 VE 2A +IN A 2 13 VE 1A V- 3 12 OUT A N/C 4 11 V+ N/C 5 10 OUT B +IN B 6 9 VE 1B -IN B 7 8 VE 2B TOP VIEW SB, PB, DB PACKAGES * N/C Pins are internally connected. Do not connect externally. Rev 2.1 (c)2011 Advanced Linear Devices, Inc. 415 Tasman Drive, Sunnyvale, CA 94089-1706 Tel: (408) 747-1155 Fax: (408) 747-1286 www.aldinc.com FUNCTIONAL DESCRIPTION Functional Description of ALD2721 The ALD2721E/ALD2721 uses EPADs as in-circuit elements for trimming of offset voltage bias characteristics. Each ALD2721E/ALD2721 has a pair of EPAD-based circuits connected such that one circuit is used to adjust VOS in one direction and the other circuit is used to adjust VOS in the other direction. While each of the EPAD devices is a monotonically adjustable programmable device, the VOS of the ALD2721E can be adjusted many times in both directions. Once programmed, the set VOS levels are stored permanently, even when the device power is removed. The ALD2721 is pre-programmed at the factory under standard operating conditions for minimum equivalent input offset voltage. The ALD2721 offers similar programmable features as the ALD2721E, but with a more limited offset voltage program range. In is intended for standard operational amplifier applications, where little or no electrical porggramming by the user is necessary. Functional Description of ALD2721E The ALD2721E is pre-programmed at the factory under standard operating conditions for minimum equivalent input offset voltage. It also has a guaranteed offset voltage program range, which is ideal for applications that require electrical offset voltage programming. The ALD2721E is an operational amplifier that can be trimmed with user application-specific programming or insystem programming conditions. User application-specific circuit programming refers to the situation where the Total Input Offset Voltage of the ALD2721E can be trimmed with the actual intended operating conditions. For example, an application circuit may have +1V and -1V power supplies, and the operational amplifier input is biased at +1V, and an average operating temperature at +85C. The circuit can be wired up to these conditions within an environmental chamber with the ALD2721E inserted into a test socket connected to this circuit while it is being electrically trimmed. Any error in VOS due to these bias conditions can be automatically zeroed out. The Total VOS error is now limited only by the adjustable range and the stability of VOS, and the input noise voltage of the operational amplifier. Therefore, this Total VOS error now includes VOS as VOS is traditionally specified; plus the VOS error contributions from PSRR, CMRR, TCVOS, and noise. Typically this total VOS error (VOST) is approximately 35V for the ALD2721E. In-System Programming refers to the condition where the EPAD adjustment is made after the ALD2721E has been inserted into a circuit board. In this case, the circuit design must provide for the ALD2721E to operate in normal mode and in programming mode. One of the benefits of in-system programming is that not only is the ALD2721E offset voltage from operating bias conditions accounted for, any residual errors introduced by other circuit components, such as resistor or sensor induced voltage errors, can also be corrected. In this way, the "in-system" circuit output can be adjusted to a desired level, eliminating the need for another trimming function. ALD2721E/ALD2721 USER PROGRAMMABLE VOS FEATURE Each ALD2721E/ALD2721 has four additional pins, compared to a conventional dual operational amplifier which has eight pins. These four additional pins are named VE1A, VE2A for op amp A and VE1B, VE2B for op amp B. Each of these pins VE1A, VE2A, VE1B, VE2B (represented by VExx) are connected to a separate, internal offset bias circuit. VExx pins have initial internal bias voltage values of approximately 1V to 2V. The voltage on these pins can be programmed using the ALD E100 EPAD Programmer and the appropriate Adapter Module. The useful programming range of voltages on VExx pins are 1V to 3V. VExx pins are programming pins, used during electrical programming mode to inject charge into the internal EPADs. Increasing voltage on VE1A/VE1B increases the offset voltage whereas increasing voltage on VE2A/VE2B decreases the offset voltage of op amp A and op amp B, respectively. The injected charge is then permanently stored. After programming, VExx pins must be left open in order for these voltages to remain at the programmed levels. During programming, voltages on VExx pins are increased incrementally to program the offset voltage of the operational amplifier to the desired VOS. Note that desired VOS can be any value within the offset voltage programmable ranges, and can be equal zero, a positive value or a negative value. This VOS value can also be reprogrammed to a different value at a later time, provided that the useful VE1x or VE2x programming voltage range has not been exceeded. VExx pins can also serve as capacitively coupled input pins. Internally, VE1 and VE2 are programmed and connected differentially. Temperature drift effects between the two internal offset bias circuits cancel each other and introduce less net temperature drift coefficient change than offset voltage trimming techniques such as offset adjustment with an external trimmer potentiometer. While programming, V+, VE1 and VE2 pins may be alternately pulsed with 12V (approximately) pulses generated by the EPAD Programmer. In-system programming requires the ALD2721E application circuit to accommodate these programming pulses. This can be accomplished by adding resistors at certain appropriate circuit nodes. For more information, see Application Note AN1700. Advanced Linear Devices 2 of 13 ABSOLUTE MAXIMUM RATINGS Supply voltage, V+ Differential input voltage range Power dissipation Operating temperature range SB, PB packages DB package Storage temperature range Lead temperature, 10 seconds CAUTION: ESD Sensitive Device. Use static control procedures in ESD controlled environment. 10.6V -0.3V to V+ +0.3V 600 mW 0C to +70C -55C to +125C -65C to +150C +260C OPERATING ELECTRICAL CHARACTERISTICS TA = 25oC VS = 2.5V unless otherwise specified Parameter Symbol Supply Voltage VS V+ Initial Input Offset Voltage1 VOS i Offset Voltage Program Range 2 VOS Programmed Input Offset Voltage Error 3 VOS Total Input Offset Voltage 4 VOST Input Offset Current 5 Min 2721E Typ 1.0 2.0 Max 5.0 10.0 35 5 2721 Typ 1.0 2.0 100 7 50 Min 50 0.5 100 Max Unit Test Conditions 5.0 10.0 V V Dual Supply Single Supply 150 V RS 100K 2 50 mV 150 V At user specified target offset voltage 50 100 50 150 V At user specified target offset voltage IOS 0.01 10 240 0.01 10 240 pA pA TA = 25C 0C TA +70C Input Bias Current 5 IB 0.01 10 240 0.01 10 240 pA pA TA = 25C 0C TA +70C Input Voltage Range 6 VIR 5.3 +2.8 V V V+ = +5V VS = 2.5V Input Resistance RIN Input Offset Voltage Drift 7 -0.3 -2.8 5.3 +2.8 -0.3 -2.8 1014 1014 TCVOS 7 7 Initial Power Supply Rejection Ratio 8 PSRR i 90 Initial Common Mode CMRR i 90 V/C RS 100K 90 dB RS 100K 90 dB RS 100K V/mV V/mV RL =100K 0C TA +70C V V RL =1M V =5V 0C TA +70C V V RL =100K 0C TA +70C Rejection Ratio 8 Large Signal Voltage Gain AV Output Voltage Range Output Short Circuit Current 15 10 100 VO low VO high 4.99 4.999 VO low VO high 2.40 -2.48 2.48 0.001 ISC 15 10 100 4.99 4.999 2.40 -2.48 2.48 0.01 0.001 -2.40 1 1 0.01 -2.40 mA * NOTES 1 through 9, see section titled "Definitions and Design Notes". ALD2721E/ALD2721 Advanced Linear Devices 3 of 13 OPERATING ELECTRICAL CHARACTERISTICS (cont'd) TA = 25oC VS = 2.5V unless otherwise specified 2721E Typ Max IS 200 Power Dissipation PD 1.00 Input Capacitance CIN 1 1 pF Maximum Load Capacitance CL 50 50 pF Equivalent Input Noise Voltage en 55 55 nV/Hz f = 1KHz Equivalent Input Noise Current in 0.6 0.6 fA/Hz f =10Hz Bandwidth BW 700 700 KHz Slew Rate SR 0.7 0.7 V/s AV = +1 RL = 100K Rise time tr 0.2 0.2 s RL = 100K 20 20 % RL=100K CL=50pF Parameter Symbol Supply Current Min Overshoot Factor 2721 Typ Max 400 200 400 A VIN = 0V No Load 2.00 1.00 2.00 mW VS = 2.5V Min Unit Test Conditions Settling Time tS 10 10 s 0.1% AV = -1 RL= 100K CL = 50pF Channel Separation CS 140 140 dB AV =100 TA = 25oC VS = 2.5V unless otherwise specified 2721E Parameter Symbol Average Long Term Input Offset Voltage Stability 9 VOS time Initial VE Voltage VE1 i, VE2 i Programmable Change of VE Range VE1, VE2 Programmed VE Voltage Error e(VE1-VE2) VE Pin Leakage Current ieb Min Typ 2721 Max Min 0.02 Typ 0.02 Max Unit Test Conditions V/ 1000 hrs 1.5 1.2 1.7 V 2.5 1.0 V 0.1 0.1 % -5 -5 A * NOTES 1 through 9, see section titled "Definitions and Design Notes". ALD2721E/ALD2721 Advanced Linear Devices 4 of 13 OPERATING ELECTRICAL CHARACTERISTICS (cont'd) VS = 2.5V -55C TA +125C unless otherwise specified 2721E Min Typ 2721 Parameter Symbol Max Min Initial Input offset Voltage VOS i Input Offset Current IOS 2.0 2.0 nA Input Bias Current IB 2.0 2.0 nA Initial Power Supply PSRR i 85 85 dB RS 100K Initial Common Mode Rejection Ratio 8 CMRR i 83 83 dB RS 100K Large Signal Voltage Gain AV 15 50 V/mV RL = 100K Output Voltage Range VO low VO high 2.35 V V RL = 100K Unit Test Conditions 0.7 Typ Max 0.7 Unit Test Conditions mV RS 100K Rejection Ratio 8 50 -2.47 2.45 15 -2.40 2.35 -2.47 2.45 -2.40 TA = 25oC VS = 5.0V unless otherwise specified 2721E Min Symbol Initial Power Supply 8 Rejection Ratio PSRR i 85 85 dB RS 100K Initial Common Mode 8 Rejection Ratio CMRRi 83 83 dB RS 100K Large Signal Voltage Gain AV 250 250 V/mV RL = 100K Output Voltage Range VO low VO high V RL = 100K 4.90 Typ 2721 Parameter -4.98 4.98 Max Min -4.90 4.90 Typ -4.98 4.98 Max -4.90 Bandwidth BW 1.0 1.0 MHz Slew Rate SR 1.0 1.0 V/s ALD2721E/ALD2721 Advanced Linear Devices AV = +1, CL = 50pF 5 of 13 DEFINITIONS AND DESIGN NOTES: ADDITIONAL DESIGN NOTES: 1. Initial Input Offset Voltage is the initial offset voltage of the ALD2721E/ALD2721 operational amplifier when shipped from the factory. The device has been pre-programmed and tested for programmability. A. The ALD2721E/ALD2721 is internally compensated for unity gain stability using a novel scheme which produces a single pole role off in the gain characteristics while providing more than 70 degrees of phase margin at unity gain frequency. A unity gain buffer using the ALD2721E/ALD2721 will typically drive 50pF of external load capacitance. 2. Offset Voltage Program Range is the range of adjustment of user specified target offset voltage. This is typically an adjustment in either the positive or the negative direction of the input offset voltage from an initial input offset voltage. The input offset programming pins, VE1A/VE1B or VE2A/VE2B, change the input offset voltage in the negative or positive direction, for each of the amplifiers, A or B respectively. User specified target offset voltage can be any offset voltage within this programming range. 3. Programmed Input Offset Voltage Error is the final offset voltage error after programming when the Input Offset Voltage is at target Offset Voltage. This parameter is sample tested. 4. Total Input Offset Voltage is the same as Programmed Input Offset Voltage, corrected for system offset voltage error. Usually this is an all inclusive system offset voltage, which also includes offset voltage contributions from input offset voltage, PSRR, CMRR, TCVOS and noise. It can also include errors introduced by external components, at a system level. Programmed Input Offset Voltage and Total Input Offset Voltage is not necessarily zero offset voltage, but an offset voltage set to compensate for other system errors as well. This parameter is sample tested. 5. The Input Offset and Bias Currents are essentially input protection diode reverse bias leakage currents. This low input bias current assures that the analog signal from the source will not be distorted by it. For applications where source impedance is very high, it may be necessary to limit noise and hum pickup through proper shielding. 6. Input Voltage Range is determined by two parallel complementary input stages that are summed internally, each stage having a separate input offset voltage. While Total Input Offset Voltage can be trimmed to a desired target value, it is essential to note that this trimming occurs at only one user selected input bias voltage. Depending on the selected input bias voltage relative to the power supply voltages, offset voltage trimming may affect one or both input stages. For the ALD2721E/ ALD2721, the switching point between the two stages occurs at approximately 1.5V below the positive supply voltage. 7. Input Offset Voltage Drift is the average change in Total Input Offset Voltage as a function of ambient temperature. This parameter is sample tested. 8. Initial PSRR and initial CMRR specifications are provided as reference information. After programming, error contribution to the offset voltage from PSRR and CMRR is set to zero under the specific power supply and common mode conditions, and becomes part of the Programmed Input Offset Voltage Error. 9. Average Long Term Input Offset Voltage Stability is based on input offset voltage shift through operating life test at 125C extrapolated to TA = 25C, assuming activation energy of 1.0eV. This parameter is sample tested. ALD2721E/ALD2721 B. The ALD2721E/ALD2721 has complementary p-channel and n-channel input differential stages connected in parallel to accomplish rail-to-rail input common mode voltage range. The switching point between the two differential stages is 1.5V below positive supply voltage. For applications such as inverting amplifiers or non-inverting amplifiers with a gain larger than 2.5 (5V operation), the common mode voltage does not make excursions below this switching point. However, this switching does take place if the operational amplifier is connected as a railto-rail unity gain buffer and the design must allow for input offset voltage variations. C. The output stage consists of class AB complementary output drivers. The oscillation resistant feature, combined with the railto-rail input and output feature, makes the ALD2721E/ ALD2721 an effective analog signal buffer for high source impedance sensors, transducers, and other circuit networks. D. The ALD2721E/ALD2721 has static discharge protection. However, care must be exercised when handling the device to avoid strong static fields that may degrade a diode junction, causing increased input leakage currents. The user is advised to power up the circuit before, or simultaneously with, any input voltages applied and to limit input voltages not to exceed 0.3V of the power supply voltage levels. E. VExx are high impedance terminals, as the internal bias currents are set very low to a few microamperes to conserve power. For some applications, these terminals may need to be shielded from external coupling sources. For example, digital signals running nearby may cause unwanted offset voltage fluctuations. Care during the printed circuit board layout, to place ground traces around these pins and to isolate them from digital lines, will generally eliminate such coupling effects. In addition, optional decoupling capacitors of 1000pF or greater value can be added to VExx terminals. F. The ALD2721E/ALD2721 is designed for use in low voltage, micropower circuits. The maximum operating voltage during normal operation should remain below 10V at all times. Care should be taken to insure that the application in which the device is used does not experience any positive or negative transient voltages that will cause any of the terminal voltages to exceed this limit. G. All inputs or unused pins except VExx pins should be connected to a supply voltage such as Ground so that they do not become floating pins, since input impedance at these pins is very high. If any of these pins are left undefined, they may cause unwanted oscillation or intermittent excessive current drain. As these devices are built with CMOS technology, normal operating and storage temperature limits, ESD and latchup handling precautions pertaining to CMOS device handling should be observed. Advanced Linear Devices 6 of 13 TYPICAL PERFORMANCE CHARACTERISTICS OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF SUPPLY VOLTAGE AND TEMPERATURE OUTPUT VOLTAGE SWING (V) OPEN LOOP VOLTAGE GAIN (V/mV) 1000 OUTPUT VOLTAGE SWING AS A FUNCTION OF SUPPLY VOLTAGE 100 10 -55C TA +125C RL = 100K 2 4 6 -55C TA +125C RL = 100K 5 4 3 2 1 1 0 6 0 8 1 1000 4 5 6 7 500 VS = 2.5V 100 SUPPLY CURRENT (A) INPUT BIAS CURRENT (pA) 3 SUPPLY CURRENT AS A FUNCTION OF SUPPLY VOLTAGE INPUT BIAS CURRENT AS A FUNCTION OF AMBIENT TEMPERATURE 10 1.0 0.1 0.01 INPUTS GROUNDED OUTPUT UNLOADED 400 +25C -25C 300 TA = -55C 200 +125C 100 +70C 0 -50 -25 0 25 50 75 100 125 0 1 2 3 4 5 AMBIENT TEMPERATURE (C) SUPPLY VOLTAGE (V) ADJUSTMENT IN INPUT OFFSET VOLTAGE AS A FUNCTION OF CHANGE IN VE1 AND VE2 OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF FREQUENCY 6 120 OPEN LOOP VOLTAGE GAIN (dB) 10 8 6 VE1 4 2 0 -2 -4 -6 -8 VE2 -10 VS = 2.5V TA = 25C 100 80 60 0 40 45 20 90 0 135 180 -20 0.50 0.75 1.00 1.25 1.50 1.75 2.00 CHANGE IN VE1 AND VE2 (V) ALD2721E/ALD2721 Advanced Linear Devices 1 10 100 1K 10K 100K FREQUENCY (Hz) 1M PHASE SHIFT IN DEGREES ADJUSTMENT IN INPUT OFFSET VOLTAGE VOS (mV) 2 SUPPLY VOLTAGE (V) SUPPLY VOLTAGE (V) 10M 7 of 13 TYPICAL PERFORMANCE CHARACTERISTICS (cont'd) COMMON MODE INPUT VOLTAGE RANGE AS A FUNCTION OF SUPPLY VOLTAGE OPEN LOOP VOLTAGE GAIN AS A FUNCTION OF LOAD RESISTANCE 7 1000 OPEN LOOP VOLTAGE GAIN (V/mV) COMMON MODE INPUT VOLTAGE RANGE (V) 6 TA = 25C 5 4 3 2 1 100 10 VS = 2.5V TA = 25C 0 1 0 1 2 3 4 5 6 7 10K 100K SUPPLY VOLTAGE (V) 1M 10M LOAD RESISTANCE () LARGE - SIGNAL TRANSIENT RESPONSE LARGE - SIGNAL TRANSIENT RESPONSE 5V/div VS = 2.5V TA = 25C RL = 100K CL = 50pF 2V/div VS = 1.0V TA = 25C RL = 100K CL = 50pF 2V/div 5s/div 500mV/div 5s/div SMALL - SIGNAL TRANSIENT RESPONSE DISTRIBUTION OF TOTAL INPUT OFFSET VOLTAGE BEFORE AND AFTER EPAD PROGRAMMING 100mV/div VS = 2.5V TA = 25C RL = 100K CL = 50pF PERCENTAGE OF UNITS (%) 100 80 EXAMPLE A: VOST AFTER EPAD PROGRAMMING VOST TARGET = 0.0V EXAMPLE B: VOST AFTER EPAD PROGRAMMING VOST TARGET = -750V 60 VOST BEFORE EPAD PROGRAMMING 40 20 20mV/div 2s/div 0 -2500 -2000 -1500 -1000 -500 0 500 1000 1500 2000 2500 TOTAL INPUT OFFSET VOLTAGE (V) ALD2721E/ALD2721 Advanced Linear Devices 8 of 13 EQUIVALENT INPUT OFFSET VOLTAGE DUE TO CHANGE IN SUPPLY VOLTAGE (V) TYPICAL PERFORMANCE CHARACTERISTICS (cont'd) TWO EXAMPLES OF EQUIVALENT INPUT OFFSET VOLTAGE DUE TO CHANGE IN SUPPLY VOLTAGE vs. SUPPLY VOLTAGE 500 PSRR = 80 dB 400 EXAMPLE A: VOS EPAD PROGRAMMED AT VSUPPLY = +5V 300 EXAMPLE B: VOS EPAD PROGRAMMED AT VSUPPLY = +8V 200 100 0 1 0 2 3 4 5 6 7 8 9 10 EQUIVALENT INPUT OFFSET VOLTAGE DUE TO CHANGE IN COMMON MODE VOLTAGE (V) SUPPLY VOLTAGE (V) THREE EXAMPLES OF EQUIVALENT INPUT OFFSET VOLTAGE DUE TO CHANGE IN COMMON MODE VOLTAGE vs. COMMON MODE VOLTAGE 500 VSUPPLY = 5V CMRR = 80dB 400 300 EXAMPLE B: VOS EPAD PROGRAMMED AT VIN = -4.3V 200 EXAMPLE A: VOS EPAD PROGRAMMED AT VIN = 0V 100 EXAMPLE C: VOS EPAD PROGRAMMED AT VIN = +5V 0 -5 -4 -3 -1 -2 0 1 2 3 4 5 EQUIVALENT INPUT OFFSET VOLTAGE DUE TO CHANGE IN COMMON MODE VOLTAGE (V) COMMON MODE VOLTAGE (V) EXAMPLE OF MINIMIZING EQUIVALENT INPUT OFFSET VOLTAGE FOR A COMMON MODE VOLTAGE RANGE OF 0.5V 50 COMMON MODE VOLTAGE RANGE OF 0.5V 40 30 VOS EPAD PROGRAMMED AT COMMON MODE VOLTAGE OF 0.25V 20 CMRR = 80dB 10 0 -0.5 -0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4 0.5 COMMON MODE VOLTAGE (V) ALD2721E/ALD2721 Advanced Linear Devices 9 of 13 TYPICAL PERFORMANCE CHARACTERISTICS (cont'd) APPLICATION SPECIFIC / IN-SYSTEM PROGRAMMING 2500 2500 2000 2000 TOTAL INPUT OFFSET VOLTAGE (V) TOTAL INPUT OFFSET VOLTAGE (V) Examples of applications where accumulated total input offset voltage from various contributing sources is minimized under different sets of user-specified operating conditions 1500 1000 VOS BUDGET AFTER EPAD PROGRAMMING 500 0 -500 + X -1000 -1500 -2000 VOS BUDGET BEFORE EPAD PROGRAMMING 1500 VOS BUDGET AFTER EPAD PROGRAMMING 1000 500 + 0 X -500 -1000 VOS BUDGET BEFORE EPAD PROGRAMMING -1500 -2000 -2500 -2500 EXAMPLE B 2500 2500 2000 2000 TOTAL INPUT OFFSET VOLTAGE (V) TOTAL INPUT OFFSET VOLTAGE (V) EXAMPLE A 1500 1000 VOS BUDGET BEFORE EPAD PROGRAMMING 500 0 -500 -1000 + X -1500 -2000 VOS BUDGET AFTER EPAD PROGRAMMING 1500 1000 500 + 0 X -500 -1000 -1500 -2000 -2500 VOS BUDGET AFTER EPAD PROGRAMMING VOS BUDGET BEFORE EPAD PROGRAMMING -2500 EXAMPLE C EXAMPLE D Device input VOS PSRR equivalent VOS + Total Input VOS after EPAD Programming CMRR equivalent VOS TA equivalent VOS X Noise equivalent VOS External Error equivalent VOS ALD2721E/ALD2721 Advanced Linear Devices 10 of 13 SOIC-14 PACKAGE DRAWING 14 Pin Plastic SOIC Package Millimeters E S (45) Dim A Min 1.35 Max 1.75 Min 0.053 Max 0.069 A1 0.10 0.25 0.004 0.010 b 0.35 0.45 0.014 0.018 C 0.18 0.25 0.007 0.010 D-14 8.55 8.75 0.336 0.345 E 3.50 4.05 0.140 0.160 1.27 BSC e D A Inches 0.050 BSC H 5.70 6.30 0.224 0.248 L 0.60 0.937 0.024 0.037 o 0 8 0 8 S 0.25 0.50 0.010 0.020 A1 e b S (45) H L ALD2721E/ALD2721 C o Advanced Linear Devices 11 of 13 PDIP-14 PACKAGE DRAWING 14 Pin Plastic DIP Package Millimeters E E1 D S A2 A1 A L Inches Dim A Min Max Min 3.81 5.08 0.105 Max 0.200 A1 0.38 1.27 0.015 0.050 A2 1.27 2.03 0.050 0.080 b 0.89 1.65 0.035 0.065 b1 0.38 0.51 0.015 0.020 c 0.20 0.30 0.008 0.012 D-14 17.27 19.30 0.680 0.760 E 5.59 7.11 0.220 0.280 E1 7.62 8.26 0.300 0.325 e 2.29 2.79 0.090 0.110 e1 7.37 7.87 0.290 0.310 L 2.79 3.81 0.110 0.150 S-14 1.02 2.03 0.040 0.080 o 0 15 0 15 e b b1 c e1 ALD2721E/ALD2721 o Advanced Linear Devices 12 of 13 CERDIP-14 PACKAGE DRAWING 14 Pin CERDIP Package Millimeters E E1 D A1 s A L L1 L2 b b1 e Inches Dim A Min Max Min Max 3.55 5.08 0.140 0.200 A1 1.27 2.16 0.050 0.085 b 0.97 1.65 0.038 0.065 b1 0.36 0.58 0.014 0.023 C 0.20 0.38 0.008 0.015 D-14 -- 19.94 -- 0.785 E 5.59 7.87 0.220 0.310 E1 7.73 8.26 0.290 0.325 e 2.54 BSC 0.100 BSC e1 7.62 BSC 0.300 BSC L 3.81 5.08 0.150 0.200 L1 3.18 -- 0.125 -- L2 0.38 1.78 0.015 0.070 S -- 2.49 -- 0.098 O 0 15 0 15 C e1 ALD2721E/ALD2721 o Advanced Linear Devices 13 of 13