SP809 / SP810 3 Pin Microprocessor Supervisor Circuit February 2011 Rev. 2.0.0 GENERAL DESCRIPTION APPLICATIONS The SP809/SP810 are low power microprocessor (P) supervisory circuits used to monitor power supplies in P and digital systems. * Portable Electronic Devices They provide applications with benefits of circuit reliability and low cost by eliminating external components. If the VCC supply voltage falls below preset threshold then a reset signal is asserted for at least 140ms after VCC has risen above the reset threshold. * P Power Monitoring Both the SP809 and SP810 were designed with a reset comparator to help identify invalid signals, which last less than 140ms. The only difference between them is that they have an active-low RESET output and active-high RESET output, respectively. Low supply current (1A) makes SP809/SP810 ideal for portable equipment. * Electrical Power Meters * Digital Still Cameras FEATURES * Ultra Low Supply Current 1A (typ) * Guaranteed Reset valid to VCC = 0.9V * 140ms Power-On Reset Pulse Width * Internally Fixed Threshold 2.3V, 2.6V, 2.9V, 3.1V, 4.4V, 4.6V * 1.5% Voltage Threshold Tolerance * 3 Pin SOT-23 Package The devices are available in 3 pin SOT-23 package. Part Number Output Type SP809N SP809 SP810 Open Drain Active Low Push-Pull Low Push-Pull Active High TYPICAL APPLICATION DIAGRAM Fig. 1: SP809 / SP810 Application Diagram Exar Corporation 48720 Kato Road, Fremont CA 94538, USA www.exar.com Tel. +1 510 668-7000 - Fax. +1 510 668-7001 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit ABSOLUTE MAXIMUM RATINGS OPERATING RATINGS These are stress ratings only and functional operation of the device at these ratings or any other above those indicated in the operation sections of the specifications below is not implied. Exposure to absolute maximum rating conditions for extended periods of time may affect reliability. Input Voltage Range VCC ................................ 0.9V to 6V Junction Temperature Range ..................... -40C to 85C VCC .......................................................... -0.3V to 6.5V RESET, RESET .................................... -0.3V to VCC+0.3V Output Current (RESET, RESET) ............................. 20mA Power Dissipation (TA=70C) .............................. 320mW Junction Temperature .......................................... 125C Storage Temperature .............................. -65C to 150C ELECTRICAL SPECIFICATIONS Specifications with standard type are for an Operating Temperature of TA = 25C only; limits applying over the full Operating Temperature range are denoted by a "*". Minimum and Maximum limits are guaranteed through test, design, or statistical correlation. Typical values represent the most likely parametric norm at TA = 25C, and are provided for reference purposes only. Unless otherwise indicated, TA= 25C. Parameter Operating Voltage Range VCC Min. Typ. 2.265 6.0 V 3.0 A 2.3 2.335 2.6 2.857 Reset Threshold VTH 2.9 3.054 3.1 4.4 4.6 VCC Reset Delay VTRIP Reset Active Timeout Period TRP RESET Output Voltage VOH 100 RESET Output Voltage VOL 1030 0.3 0.8VCC 0.3 TA=-40C to 85C TA=+25C * TA=-40C to 85C TA=+25C * ms V V TA=-40C to 85C VCC=VTH to (VTH + 0.1V), VTH=3.1V s 560 TA=-40C to 85C TA=+25C * 4.669 0.8VCC RESET Output Voltage VOL RESET Output Voltage VOH 230 * 4.466 20 140 V 4.692 4.508 TA=-40C to 85C TA=+25C 4.488 4.312 4.531 3.147 TA=-40C to 85C TA=+25C * 3.162 3.038 4.334 * 2.944 2.958 2.842 VCC=VTH+0.1V 2.639 2.652 2.548 Conditions TA=+25C 2.346 2.254 2.561 Units 1.0 0.9 Supply Current ICC Max. TA=+25C * TA=-40C to 85C VCC=VTH - 0.1V, ISOURCE = 1.2mA VCC=VTH + 0.1V, ISINK = 1.2mA VCC=VTH + 0.1V, ISOURCE = 1.2mA VCC=VTH - 0.1V, ISINK = 1.2mA Note 1: RESET output is for SP809; RESET output is for SP810. (c) 2011 Exar Corporation 2/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit BLOCK DIAGRAM Fig. 2: SP809 / SP810 Block Diagram PIN ASSIGNMENT Fig. 3: SP809 / SP810 Pin Assignment PIN DESCRIPTION Name Pin Number GND 1 RESET 2 RESET VCC 3 (c) 2011 Exar Corporation Description Ground Signal Active Low Output Pin. RESET Output remains high while VCC is below the reset threshold Active High Output Pin. RESET Output remains high while VCC is below the reset threshold Supply Voltage 3/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit ORDERING INFORMATION Temperature Range Marking SP809EK-L-2-3/TR -40CTA+85C N4WW SP809EK-L-2-6/TR -40CTA+85C P4WW SP809EK-L-2-9/TR -40CTA+85C Q4WW SP809EK-L-3-1/TR -40CTA+85C R4WW SP809EK-L-4-6/TR -40CTA+85C U4WW SP809NEK-L-2-3/TR -40CTA+85C SP809NEK-L-2-9/TR -40CTA+85C V4WW Part Number Packing Quantity Package SOT23-3 Note 1 Note 2 2.5K/Tape & Reel Lead Free X4WW Y4WW SP809NEK-L-3-1/TR -40CTA+85C SP809NEK-L-4-6/TR -40CTA+85C C5WW SP810EK-L-2-6/TR -40CTA+85C E5WW SP810EK-L-4-4/TR -40CTA+85C J5WW "YY" = Year - "WW" = Work Week - "X" = Lot Number; when applicable. (c) 2011 Exar Corporation 4/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit TYPICAL PERFORMANCE CHARACTERISTICS All data taken at TA = 25C, unless otherwise specified - Schematic and BOM from Application Information section of this datasheet. Fig. 4: Supply Current versus Temperature Fig. 5: Power-Down Reset Delay versus Temperature Fig. 6: Power-Down Reset Delay versus Temperature Fig. 7: Power-Down Reset Delay versus Temperature Fig. 8: Normalized Reset Threshold versus Temperature Fig. 9: Power-Up Reset Time-out versus Temperature (c) 2011 Exar Corporation 5/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit VCC returns above the reset threshold, and RESET remains low for the reset timeout period. THEORY OF OPERATION P will be activated at a valid reset state. These P supervisory circuits assert reset to prevent code execution errors during powerup, power-down, or brownout conditions. BENEFIT OF HIGHLY ACCURATE RESET THRESHOLD Reset is guaranteed to be a logic low for VTH>VCC>0.9V. Once VCC exceeded the reset threshold, an internal timer keeps RESET low for the reset timeout period; after this interval, RESET goes high. SP809/810 with specified voltage as 5V10% or 3V10% are ideal for systems using a 5V5% or 3V5% power supply. The reset is guaranteed to assert after the power supply falls below the minimum specified operating voltage range of the system ICs. The pretrimmed thresholds are reducing the range over which an undesirable reset may occur. If a brownout condition occurs (VCC drops below the reset threshold), RESET goes low. Any time VCC goes below the reset threshold, the internal timer resets to zero, and RESET goes low. The internal timer is activated after APPLICATION INFORMATION INTERFACING TO P WITH BIDIRECTIONAL RESET PINS NEGATIVE GOING VCC TRANSIENTS The RESET output on the SP809N is open drain, this device interfaces easily with Ps that have bidirectional reset pins. Connecting the P supervisor's RESET output directly to the microcontroller's RESET pin with a single pull-up resistor allows either device to assert reset. In addition to issuing a reset to the P during power-up, power-down, and brownout conditions, SP809 series are relatively resistant to short-duration negative-going VCC transient. ENSURING A VALID RESET OUTPUT DOWN TO VCC=0 TEST CIRCUIT When VCC falls below 0.9V, SP809 RESET output no longer sinks current; it becomes an open circuit. In this case, high-impedance CMOS logic inputs connecting to RESET can drift to undetermined voltages. Therefore, SP809/810 with CMOS is perfect for most applications of VCC down to 0.9V. However in applications where RESET must be valid down to 0V, adding a pull-down resistor to RESET causes any leakage currents to flow to ground, holding RESET low. (c) 2011 Exar Corporation Fig. 10: Test Circuit 6/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit PACKAGE SPECIFICATION 3-PIN SOT23 (c) 2011 Exar Corporation 7/8 Rev. 2.0.0 SP809 / SP810 3 Pin Microprocessor Supervisor Circuit REVISION HISTORY Revision Date 2.0.0 Description Reformat of Datasheet Correction of package drawing FOR FURTHER ASSISTANCE Email: customersupport@exar.com Exar Technical Documentation: http://www.exar.com/TechDoc/default.aspx? EXAR CORPORATION HEADQUARTERS AND SALES OFFICES 48720 Kato Road Fremont, CA 94538 - USA Tel.: +1 (510) 668-7000 Fax: +1 (510) 668-7030 www.exar.com NOTICE EXAR Corporation reserves the right to make changes to the products contained in this publication in order to improve design, performance or reliability. EXAR Corporation assumes no responsibility for the use of any circuits described herein, conveys no license under any patent or other right, and makes no representation that the circuits are free of patent infringement. Charts and schedules contained here in are only for illustration purposes and may vary depending upon a user's specific application. While the information in this publication has been carefully checked; no responsibility, however, is assumed for inaccuracies. EXAR Corporation does not recommend the use of any of its products in life support applications where the failure malfunction of the product can reasonably be expected to cause failure of the life support system or to significantly affect safety or effectiveness. Products are not authorized for use in such applications unless EXAR Corporation receives, writing, assurances to its satisfaction that: (a) the risk of injury or damage has been minimized; (b) the user assumes such risks; (c) potential liability of EXAR Corporation is adequately protected under the circumstances. or its in all Reproduction, in part or whole, without the prior written consent of EXAR Corporation is prohibited. (c) 2011 Exar Corporation 8/8 Rev. 2.0.0