ADM698SQ

ADM698SQ Datasheet


GENERAL DESCRIPTION The ADM698/ADM699 supervisory circuits provide power supply monitoring and watchdog timing for microprocessor systems. The ADM698 monitors the 5 V VCC power supply and generates a RESET pulse during power up, power down and during low voltage “Brown Out” conditions. The RESET output is guaranteed to be functional logic low with VCC as low as 1 V. The ADM699 features an identical monitoring circuit as in the ADM698 plus an additional watchdog timer input to monitor microprocessor activity. The RESET output is forced low if the watchdog input is not toggled within the 1 second watchdog timeout period. Both parts are available in 8-pin plastic DIP and 16-lead SOIC packages. The 16-lead SOIC contains additional outputs RESET without inversion and Watchdog Output WDO ADM699 only .

Part Datasheet
ADM698SQ ADM698SQ ADM698SQ (pdf)
Related Parts Information
ADM699SQ ADM699SQ ADM699SQ
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FEATURES Superior Upgrade for MAX698/MAX699 Guaranteed RESET Assertion with VCC = 1 V Low mA Supply Current Precision V Voltage Monitor Power OK/Reset Time Delay Watchdog Timer Minimum Component Count Performance Specified over Temperature

APPLICATIONS Microprocessor Systems Computers Controllers Intelligent Instruments Automotive Systems Critical Power Monitoring

GENERAL DESCRIPTION The ADM698/ADM699 supervisory circuits provide power supply monitoring and watchdog timing for microprocessor systems. The ADM698 monitors the 5 V VCC power supply and generates a RESET pulse during power up, power down and during low voltage “Brown Out” conditions. The RESET output is guaranteed to be functional logic low with VCC as low as 1 V. The ADM699 features an identical monitoring circuit as in the ADM698 plus an additional watchdog timer input to monitor microprocessor activity. The RESET output is forced low if the watchdog input is not toggled within the 1 second watchdog timeout period. Both parts are available in 8-pin plastic DIP and 16-lead SOIC packages. The 16-lead SOIC contains additional outputs RESET without inversion and Watchdog Output WDO ADM699 only .

Microprocessor Supervisory Circuits ADM698/ADM699

FUNCTIONAL BLOCK DIAGRAM

VCC 4.65V

ADM698/ ADM699

RESET GENERATOR

WATCHDOG INPUT WDI*

WATCHDOG TRANSITION DETECTOR
1 sec

RESET* RESET

WATCHDOG OUTPUT WDO*
*WDI ADM699 ONLY RESET SOIC ONLY WDO ADM699 SOIC ONLY

TYPICAL APPLICATION CIRCUIT

VCC RESET
µP POWER µP RESET

ADM698/ ADM699

WDI*
µP SYSTEM

I/O LINE
*ADM699 ONLY

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= +5 V 10%, TA = TMIN to TMAX unless otherwise noted

Parameter

Units Test Conditions/Comments

VCC Operating Voltage Range Supply Current

Power-Down Reset Assertion Power-Up Reset Deassertion Reset Threshold Hysteresis Reset Active Time

Watchdog Timeout Period ADM699 Minimum WDI Input Pulse Width

RESET Output Voltage RESET Output Voltage VCC = 1 V

RESET and WDO Output Voltage

RESET Output Short Circuit Current

TA = +25°C, VCC = +5 V

TA = +25°C, VCC = +5 V

VIL = VIH = V

ISINK = mA, Vcc = V

ISINK = 10 µA, VCC = V

ISOURCE = 1 µA, VCC = 5 V
ORDERING GUIDE

Temperature Range
to +85°C to +85°C to +85°C to +125°C
to +85°C to +85°C to +85°C to +125°C

Package Option

N-8 R-16 Q-8 Q-8

N-8 R-16 Q-8 Q-8

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 the ADM698/ADM699 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.

WARNING!

ESD SENSITIVE DEVICE

PIN FUNCTION DESCRIPTION

Mnemonic Function

VCC GND RESET

RESET WDO
+5 V Power Supply Input.
0 V. Ground reference for all signals.

Logic Output. RESET goes low whenever VCC falls below the reset voltage threshold V typ . RESET remains low for a minimum of 140 ms after VCC returns to 5 V. RESET also goes low for a minimum of 140 ms if the watchdog timer is enabled but not serviced within its timeout period.

Watchdog Input. WDI is a three level input. If WDI remains either high or low for longer than the watchdog timeout period, RESET pulses low and WDO goes low. The timer resets with each transition on the WDI line. The watchdog timer may be disabled if WDI is left floating or is driven to midsupply.

SOIC packages only Logic Output. RESET is an active high output. It is the inverse of RESET.

SOIC ADM699 only Logic Output. The Watchdog Output, WDO, goes low if WDI remains either high or low for longer than the watchdog timeout period. WDO is set high by the next transition at WDI. If WDI is unconnected or at midsupply, the watchdog timer is disabled and WDO remains high.

TYPICAL PERFORMANCE CURVES
100 90

ADM698/ADM699

PIN CONFIGURATION DIP

VCC 1 VCC 2 GND 3

GND 4

ADM698/ ADMO699

TOP VIEW Not to Scale
8 GND 7 RESET
6 NC WDI *
* ADM699 ONLY

PIN CONFIGURATION SOIC

GND 1
16 RESET

ATDOPMV6IE9W8/ NAoDt tMo S6c9a9le

RESET NC WDO *

GND 4 TOP VIEW 13 NC

NC 5 Not to Scale 12 NC
11 NC WDI *
10 NC
9 GND
More datasheets: BXRA-40E0600-A-00 | BXRA-27E0740-A-00 | BXRA-30E0540-A-00 | BXRA-30G0540-A-00 | BXRA-30G0740-A-00 | BXRA-30E0740-A-00 | BXRA-27G0540-A-00 | BXRA-27G0740-A-00 | BXRA-40E0810-A-00 | BXRA-27E0540-A-00


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Datasheet ID: ADM698SQ 517840