Microprocessor a Supervisory Circuits ADM691A/ADM693A/ADM800L/M FUNCTIONAL BLOCK DIAGRAM FEATURES Low Power Consumption: BATT ON Precision Voltage Monitor 62% Tolerance on ADM800L/M 1 4.65V LOW LINE Reset Time Delay200 ms, or Adjustable 1 mA Standby Current V CC Automatic Battery Backup Power Switching V OUT Fast Onboard Gating of Chip Enable Signals Also Available in TSSOP Package (ADM691A) V BATT CHIP ENABLE APPLICATIONS OUTPUT CONTROL Microprocessor Systems CE CE IN OUT Computers Controllers Intelligent Instruments RESET & OSC IN RESET & RESET WATCHDOG GENERATOR Automotive Systems OSC SEL TIMEBASE RESET Critical mP Power Monitoring WATCHDOG WATCHDOG WATCHDOG WATCHDOG OUTPUT (WDO) INPUT (WDI) TRANSITION DETECTOR TIMER POWER FAIL GENERAL DESCRIPTION POWER FAIL INPUT (PFI) 1.25V OUTPUT (PFO) The ADM691A/ADM693A/ADM800L/ADM800M family of ADM691A/ADM693A supervisory circuits offers complete single chip solutions for ADM800L/ADM800M power supply monitoring and battery control functions in 1 microprocessor systems. These functions include P reset, VOLTAGE DETECTOR = 4.4V (ADM693A/ADM800M) backup-battery switchover, watchdog timer, CMOS RAM write protection, and power-failure warning. The family of products provides an upgrade for the MAX691A/93A/800M family of products. INPUT POWER +5V All parts are available in 16-pin DIP and SO packages. The 7805 0.1F V ADM691A is also available in a space-saving TSSOP package. CC CMOS The following functionality is provided: RAM V V BAT 1. Power-on reset output during power-up, power-down and OUT CC V ON BATT ADDRESS CE BATTERY OUT brownout conditions. The circuitry remains operational with R1 DECODE CE ADM691A IN V as low as 1 V. CC ADM693A A0A15 P ADM800L POWER PFI 2. Battery backup switching for CMOS RAM, CMOS micro- ADM800M GND WDI I/O LINE processor or other low power logic. R2 PFO NMI OSC IN P NC RESET RESET 3. A reset pulse if the optional watchdog timer has not been OSC SEL toggled within a specified time. LOW LINE WDO 4. A 1.25 V threshold detector for power fail warning, low bat- tery detection, or to monitor a power supply other than +5 V. SYSTEM STATUS INDICATORS Figure 1. Typical Application REV. 0 Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or Tel: 617/329-4700 World Wide Web Site: ADM691A/ADM693A/ADM800L/MSPECIFICATIONS (V = 4.75 V to 5.5 V (ADM691A, ADM800L) 4.5 V to 5.5 V (ADM693A, ADM800M) V = +2.8 V, T = T to T unless otherwise noted) CC BATT A MIN MAX Parameter Min Typ Max Unit Test Conditions/Comments BATTERY BACKUP SWITCHING V , V Operating Voltage Range 0 5.5 V CC BATT V Output Voltage V 0.05 V 0.02 V I = 25 mA OUT CC CC OUT V 0.3 V 0.2 V I = 250 mA CC CC OUT V to V Output Resistance 0.8 1.2 V = 4.5 V CC OUT CC V in Battery Backup Mode V 0.3 V V = 4.5 V, I = 20 mA OUT BATT BATT OUT V 0.25 V V = 2.8 V, I = 10 mA BATT BATT OUT V 0.15 V V = 2.0 V, I = 5 mA BATT BATT OUT V to V Output Resistance 12 V = 4.5 V BATT OUT BATT 20 V = 2.8 V BATT 25 V = 2.0 V BATT Supply Current (Excludes I ) 70 100 AV > (V 1 V) OUT CC BATT Supply Current in B. Backup (Excludes I ) 0.04 1 AV < (V 1.2 V), V = 2.8 V OUT CC BATT BATT Battery Standby Current 5.5 V > V > V + 0.2 V CC BATT (+ = Discharge, = Charge) 0.1 +0.02 A(V +0.2 V) < V , T = +25C BATT CC A 1.0 +0.02 A(V +0.2 V) < V BATT CC Battery Switchover Threshold V + 0.03 V Power Up BATT V V V 0.03 V Power Down CC BATT BATT Battery Switchover Hysteresis 60 mV BATT ON Output Voltage Low 0.1 0.4 V I = 3.2 mA SINK 0.7 1.5 V I = 25 mA SINK BATT ON Output Short Circuit Current 60 mA Sink Current 1 15 100 A Source Current RESET AND WATCHDOG TIMER Reset Voltage Threshold ADM691A, ADM800L 4.5 4.65 4.75 V ADM693A, ADM800M 4.25 4.40 4.50 V ADM800L, V Falling 4.55 4.70 V T = +25C CC A ADM800M, V Falling 4.3 4.45 V T = +25C CC A Reset Threshold Hysteresis 15 mV V to RESET Delay 80 s Power Down CC LOW LINE to RESET Delay 800 ns Reset Timeout Period Internal Oscillator 140 200 280 ms Power Up Reset Timeout Period External Clock 2048 Cycles Power Up Watchdog Timeout Period, Internal Oscillator 1.0 1.6 2.25 s Long Period 70 100 140 ms Short Period Watchdog Timeout Period, External Clock 4096 Cycles Long Period 1024 Cycles Short Period Minimum WDI Input Pulse Width 100 ns V = 0.4, V = 0.75 V IL IH CC RESET Output Voltage 0.004 0.3 V I = 50 A, V = 1 V, V = 0 V SINK CC BATT 0.1 0.4 V I = 3.2 mA, V = 4.25 V SINK CC 3.5 V I = 1.6 mA, V = 5 V SOURCE CC RESET Output Short Circuit Current 7 20 mA RESET Output Voltage Low 0.1 0.4 V I = 3.2 mA SINK LOW LINE Output Voltage 0.4 V I = 3.2 mA, V = 4.25 V SINK CC 3.5 V I = 1 A, V = 5 V SOURCE CC LOW LINE Short Circuit Source Current 1 15 100 A WDO Output Voltage 0.4 V I = 3.2 mA, V = 4.25 V SINK CC 3.5 V I = 500 A, V = 5 V SOURCE CC WDO Short Circuit Source Current 3 10 mA WDI Input Threshold Logic Low 0.8 V Logic High 0.75 V V CC WDI Input Current 50 10 A WDI = 0 V 20 50 A WDI = V OUT POWER FAIL DETECTOR PFI Input Threshold ADM69xA 1.2 1.25 1.3 V V = 5 V CC PFI Input Threshold ADM800L/M 1.225 1.25 1.275 V V = 5 V CC PFI Input Current 0.01 25 nA PFO Output Voltage 0.4 V I = 3.2 mA SINK 3.5 I = 1 A SOURCE PFO Short Circuit Source Current 1 15 100 A PFI to PFO Delay 25 sV = 20 mV IN 60 sV = 20 mV IN REV. 0 2