nanoPower Supervisor and Watchdog Timer
Ultra-Low-Current Supervisor with Dynamic Watchdog in Tiny SOT Package
DescriptionThe MAX16152/MAX16153/MAX16154/MAX16155 ultra-low-current supervisory circuits monitor a single system supply voltage and the integrity of code execution by a microprocessor or microcontroller. These supervisors assert the reset output whenever the VCC supply voltage is greater than the minimum operating voltage, but less than the reset threshold. After the supply voltage rises above the reset threshold, the reset output remains asserted for the reset timeout period, and then de-asserts. Reset voltage thresholds are available from 1.50V to 5.0V in approximately 100mV increments.
A watchdog timer circuit monitors microprocessor or microcontroller activity. During normal operation, the microprocessor or microcontroller should repeatedly toggle the watchdog input (WDI) before the supervisor’s watchdog timeout period elapses to confirm that the system is executing code properly. If the microprocessor or microcontroller does not provide a valid watchdog input transition before the timeout period expires, the supervisor asserts a watchdog (active-low WDO) output to signal that the system is not executing code as expected. The watchdog output pulse can be used to reset the microprocessor or microcontroller, or it may be used to interrupt the system to warn of execution errors. The MAX16152 and MAX16153 feature a manual reset input (active-low MR) to allow an external pushbutton or logic signal to initiate a reset pulse. The MAX16154 and MAX16155 feature a logic input (WD_EN) that allows the system to enable and disable the watchdog function.
The MAX16152 and MAX16154 are offered in a 0.86mm x 1.27mm, 6-bump WLP, while the MAX16153 and MAX16155 are offered in 6-pin SOT23 package. All devices operate over the -40°C to +125°C temperature range.
- 400nA (typ) Supply Current
- 1.2V to 5.5V Operating Supply Range
- Monitors Supply Voltage and Provides System Reset Signal
- 1.5V to 5V Input Threshold Range in 100mV Increments
- Watchdog Function Detects Faulty Code Execution
- Open-Drain Reset and Watchdog Outputs
- Watchdog Timer Enable Input
- 6-Bump WLP Package
- 6-Pin SOT23 Package
- -40°C to +125°C Operating Temperature Range
- Glucose Monitors/Patient Monitor
- Portable/Battery-Powered Equipment
- Tablets/e-Readers/Mobile Devices
|Part Number||Reset Thresh.|
|Reset Out||tRESET||Watchdog Feature||Watchdog Timeout||Supervisor Features||Reset Thresh. Accur.|
|min||@ +25°C||See Notes|
|Adjustable||Watchdog Timer Enable Input||2.5|
|Part Number||Watchdog Startup Delay||Watchdog Output||Package/Pins|
|Device||Fab Process||Technology||Sample size||Rejects||FIT at 25°C||FIT at 55°C||Material Composition|