Preliminary Technical Data Low Voltage Supervisory Circuits with Watchdog & Manual Reset in 5-Lead SOT-23 ADM6821–ADM6825 FEATURES FUNCTIONAL BLOCK DIAGRAM Precision Low Voltage Monitoring down to 1.8V 9 Reset Threshold Options: 1.58V to 4.63V 140ms (Min) Reset Timeout Watchdog Timer with 1.6s Timeout Manual Reset Input Reset Output Stages Push-Pull Active-Low Open-Drain Active-Low Push-Pull Active-High Low Power Consumption (3µA) Guaranteed Reset Output valid to VCC=1V Power Supply Glitch Immunity Specified from -40°C to +125°C 5-Lead SOT-23 Package VCC ADM6821 VCC RESET GENERATOR VREF MR RESET DEBOUNCE WATCHDOG DETECTOR GND WDI APPLICATIONS Microprocessor Systems Computers Controllers Intelligent Instruments Portable Equipment GENERAL DESCRIPTION The ADM6821-ADM6825 are supervisory circuits which monitor power supply voltage levels and code execution integrity in microprocessor-based systems. As well as providing power-on-reset signals, an on-chip watchdog timer can reset the microprocessor if it fails to strobe within a preset timeout period. A reset signal can also be asserted by means of an external push-button, through a manual reset input. The three parts feature different combinations of watchdog input, manual reset input and output stage configuration, as shown in table 1. Each part is available in a choice of 9 reset threshold options ranging from 1.58V to 4.63V. The reset and watchdog timeout periods are fixed at 140ms (min) and 1.6s (typ), respectively. The ADM6821-ADM6825 are available in 5-lead SOT-23 packages and typically consume only 3µA, making them suitable for use in low power portable applications. Table 1. Selection Table Part No. Watchdog Timer Manual Reset ADM6821 ADM6822 ADM6823 ADM6824 ADM6825 Yes Yes Yes Yes - Yes Yes Yes Yes Output Stage RESET RESET Open-Drain Push-Pull Push-Pull Push-Pull Push-Pull Push-Pull Push-Pull Rev. PrA Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties that may result from its use. Specifications subject to change without notice. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices. Trademarks and registered trademarks are the property of their respective companies. One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. www.analog.com Tel: 781.329.4700 Fax: 781.326.8703 © 2004 Analog Devices, Inc. All rights reserved. ADM6821–ADM6825 Preliminary Technical Data ADM6821–ADM6825—SPECIFICATIONS Table 2. VCC=4. 5V to 5.5V for ADM682_L/M, VCC=2.7V to 3.6V for ADM682_T/S/R, VCC=2.1V to 2.75V for ADM682_Z/Y, VCC=1.53V to 2.0V for ADM682_W/V, TA=-40°C to +125°C, unless otherwise noted. Parameter SUPPLY VCC Operating Voltage Range Min Typ Max Units 10 5.5 5.5 24 V V µA 30 µA 16 µA 25 µA 12 µA 20 µA 4.75 4.78 4.50 4.53 3.15 3.17 3.00 3.02 2.70 2.72 2.38 2.40 2.25 2.27 1.71 1.72 1.62 0.4 V V V V V V V V V V V V V V V V V ppm/°C mV ms ms µs V 0.3 V 0.3 V 0.3 V 1 1.2 Supply Current (WDI and MR unconnected) 7 5 RESET THRESHOLD VOLTAGE ADM682_L ADM682_M ADM682_T ADM682_S ADM682_R ADM682_Z ADM682_Y ADM682_W ADM682_V RESET THRESHOLD TEMPERATURE COEFFICIENT RESET THRESHOLD HYSTERESIS RESET TIMEOUT PERIOD 4.50 4.47 4.25 4.22 3.00 2.97 2.85 2.83 2.55 2.53 2.25 2.24 2.12 2.11 1.62 1.61 1.52 140 100 VCC TO RESET DELAY RESET Output Voltage Low RESET Output Voltage High 4.63 4.38 3.08 2.93 2.63 2.32 2.19 1.67 1.58 60 2x VTH 200 280 320 20 0.8×VCC Rev.PrA | Page 2 of 7 V Test Conditions/Comments TA=0°C to +70°C TA=--40°C to +125°C VCC=5.5V, no load, TA=--40°C to +85°C VCC=5.5V, no load, TA=--40°C to +125°C VCC=3.6V, no load, TA=--40°C to +85°C VCC=3.6V, no load, TA=--40°C to +125°C VCC=3.6V, no load, TA=--40°C to +85°C (ADM6825 only) VCC=3.6V, no load, TA=--40°C to +125°C (ADM6825 only) TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C TA=-40°C to +125°C TA=-40°C to +85°C VCC = VTH to (VTH - 100mV) VCC>=4.25V, ISINK=3.2mA, reset asserted VCC>=2.55V, ISINK=1.2mA, reset asserted VCC>=1.25V, ISINK=100uA, reset asserted VCC>=1.0V, ISINK=50uA, reset asserted, TA=-40°C to +85°C VCC>=4.75V, ISOURCE=800uA, reset not asserted Preliminary Technical Data ADM6821–ADM6825 Parameter Min 0.8×VCC Typ Max V 0.8×VCC RESET Output Voltage High Units V 0.8×VCC 0.8×VCC 0.8×VCC 0.8×VCC RESET Output Voltage Low WATCHDOG INPUT (ADM6821-ADM6824) Watchdog Timeout Period WDI Pulse Width WDI Input Threshold VIL VIH WDI Input Current 1.12 50 1.6 0.3 V 0.3 V 2.40 s ns VIL=0.4V, VIH=0.8×VCC, V V µA µA 120 -15 VWDI= VCC, time average VWDI=0, time average 160 0.3xVCC V V µs ns 75 k⍀ ns 0.7xVCC 1 MR Input Pulse Width MR Glitch Rejection MR Pull-up Resistance MR to Reset Delay 25 ABSOLUTE MAXIMUM RATINGS Table 3. TA = 25°C unless otherwise noted. θJA Thermal Impedance Lead Temperature Soldering (10 sec) Vapour Phase (60 sec) Infrared (15 sec) V 0.3xVCC MANUAL RESET INPUT (ADM6821-ADM6823/ADM6825) MR Input Threshold Parameter VCC Output Current (RESET, RESET) Operating Temperature Range Storage Temperature Range 0.4 0.7xVCC -20 Rating -0.3V to +6V 20mA -40°C to +125°C -65°C to +150°C 270°C/W 100 50 200 Test Conditions/Comments VCC>=3.15V, ISOURCE=500uA, reset not asserted VCC>=1.8V, ISOURCE=200uA, reset not asserted VCC>=4.25V, ISOURCE=800uA, reset asserted VCC>=2.55V, ISOURCE=500uA, reset asserted VCC>=1.50V, ISOURCE=100uA, reset asserted VCC>=1.0V, ISOURCE=1uA, reset asserted, TA=-40°C to +85°C VCC>=4.75V, ISINK=3.2mA, reset not asserted VCC>=3.15V, ISINK=1.2mA, reset not asserted VCC>=1.8V, ISINK=500uA, reset not asserted Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. This is a stress rating only and functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. 300°C 215°C 220°C Rev.PrA | Page 3 of 7 ADM6821–ADM6825 Preliminary Technical Data PIN CONFIGURATIONS AND FUNCTIONAL DESCRIPTIONS 5 RESET 1 GND 2 VCC ADM6821 TOP VIEW RESET 1 GND 2 (Not to Scale) MR 3 RESET 1 2 4 WDI 5 VCC MR 3 RESET 1 3 VCC TOP VIEW 4 WDI 5 VCC ADM6825 GND TOP VIEW 2 (Not to Scale) RESET 5 (Not to Scale) ADM6824 GND ADM6822/ ADM6823 TOP VIEW (Not to Scale) 4 WDI RESET 3 4 MR Table 4. Pin Functional Descriptions Pin No. 1 Name RESET (ADM6822/23/24/25) 2 3 RESET (ADM6821) GND MR (ADM6821/22/23) 4 RESET (ADM6824/ADM6825) WDI (ADM6821/22/23/24) 5 MR (ADM6825) Description Active-Low Reset Output, which is asserted whenever VCC is below the reset.threshold, VTH. Open-Drain Output Stage for ADM6822. Push-Pull Output Stage for ADM6823/24/25. Active-High Reset Output Ground Manual Reset Input. This is an active-low input which, when forced low for at least 1µs, generates a reset. Features a 52k⍀ internal pull-up. Active-High Push-Pull Reset Output. Watchdog Input. Generates a reset if the voltage on the pin remains low or high for the duration of the watchdog timeout. The timer is cleared if a logic transition occurs on this pin or if a reset is generated. Manual Reset Input. VCC Power Supply Voltage being Monitored ESD CAUTION ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although this product features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality. ` Rev.PrA | Page 4 of 7 Preliminary Technical Data ADM6821–ADM6825 ORDERING GUIDE Model ADM6821LART-RL ADM6821LART-RL7 ADM6821MART-RL ADM6821MART-RL7 ADM6821TART-RL ADM6821TART-RL7 ADM6821SART-RL ADM6821SART-RL7 ADM6821RART-RL ADM6821RART-RL7 ADM6821ZART-RL ADM6821ZART-RL7 ADM6821YART-RL ADM6821YART-RL7 ADM6821WART-RL ADM6821WART-RL7 ADM6821VART-RL ADM6821VART-RL7 ADM6822LART-RL ADM6822LART-RL7 ADM6822MART-RL ADM6822MART-RL7 ADM6822TART-RL ADM6822TART-RL7 ADM6822SART-RL ADM6822SART-RL7 ADM6822RART-RL ADM6822RART-RL7 ADM6822ZART-RL ADM6822ZART-RL7 ADM6822YART-RL ADM6822YART-RL7 ADM6822WART-RL ADM6822WART-RL7 ADM6822VART-RL ADM6822VART-RL7 ADM6823LART-RL ADM6823LART-RL7 ADM6823MART-RL ADM6823MART-RL7 ADM6823TART-RL ADM6823TART-RL7 ADM6823SART-RL ADM6823SART-RL7 ADM6823RART-RL ADM6823RART-RL7 ADM6823ZART-RL ADM6823ZART-RL7 ADM6823YART-RL ADM6823YART-RL7 Reset Threshold (V) 4.63 4.63 4.38 4.38 3.08 3.08 2.93 2.93 2.63 2.63 2.32 2.32 2.19 2.19 1.67 1.67 1.58 1.58 4.63 4.63 4.38 4.38 3.08 3.08 2.93 2.93 2.63 2.63 2.32 2.32 2.19 2.19 1.67 1.67 1.58 1.58 4.63 4.63 4.38 4.38 3.08 3.08 2.93 2.93 2.63 2.63 2.32 2.32 2.19 2.19 Temperature Range -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C Rev. PrA | Page 5 of 7 Quantity 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k Package Type SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 Branding N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0A N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0B N0C N0C N0C N0C N0C N0C N0C N0C N0C N0C N0C N0C N0C N0C ADM6821–ADM6825 Preliminary Technical Data ORDERING GUIDE (CONTD.) Model ADM6823WART-RL ADM6823WART-RL7 ADM6823VART-RL ADM6823VART-RL7 ADM6824LART-RL ADM6824LART-RL7 ADM6824MART-RL ADM6824MART-RL7 ADM6824TART-RL ADM6824TART-RL7 ADM6824SART-RL ADM6824SART-RL7 ADM6824RART-RL ADM6824RART-RL7 ADM6824ZART-RL ADM6824ZART-RL7 ADM6824YART-RL ADM6824YART-RL7 ADM6824WART-RL ADM6824WART-RL7 ADM6824VART-RL ADM6824VART-RL7 ADM6825LART-RL ADM6825LART-RL7 ADM6825MART-RL ADM6825MART-RL7 ADM6825TART-RL ADM6825TART-RL7 ADM6825SART-RL ADM6825SART-RL7 ADM6825RART-RL ADM6825RART-RL7 ADM6825ZART-RL ADM6825ZART-RL7 ADM6825YART-RL ADM6825YART-RL7 ADM6825WART-RL ADM6825WART-RL7 ADM6825VART-RL ADM6825VART-RL7 Reset Threshold (V) 1.67 1.67 1.58 1.58 4.63 4.63 4.38 4.38 3.08 3.08 2.93 2.93 2.63 2.63 2.32 2.32 2.19 2.19 1.67 1.67 1.58 1.58 4.63 4.63 4.38 4.38 3.08 3.08 2.93 2.93 2.63 2.63 2.32 2.32 2.19 2.19 1.67 1.67 1.58 1.58 Temperature Range -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C -40°C to +125°C Rev.PrA | Page 6 of 7 Quantity 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k 10k 3k Package Type SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 SOT-23-5 Branding N0C N0C N0C N0C N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0D N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E N0E Preliminary Technical Data ADM6821–ADM6825 OUTLINE DIMENSIONS 2.90 BSC 5 4 2.80 BSC 1.60 BSC 1 2 3 PIN 1 0.95 BSC 1.90 BSC 1.30 1.15 0.90 1.45 MAX 0.15 MAX 0.50 0.3 0.22 0.08 SEATING PLANE 10 5 0 COMPLIANT TO JEDEC STANDARDS MO-178AA Figure 1. 5-Lead Small Outline Transistor Package [SOT-23] (RT-5) Dimensions shown in millimeters © 2004 Analog Devices, Inc. All rights reserved. Trademarks and registered trademarks are the property of their respective companies. Printed in the U.S.A. PR04535-0-2/04(PrA) Rev. PrA | Page 7 of 7 0.$ 0.45 0.3