The TPS3619 and TPS3620 families of supervisory circuits monitor and control processor activity by providing backup-battery switchover for data retention of CMOS RAM.
During power on, RESET is asserted when the supply voltage (VDD or VBAT) becomes higher than 1.1 V. Thereafter, the supply voltage supervisor monitors VDD and keeps RESET output active as long as VDD remains below the threshold voltage (VIT). An internal timer delays the return of the output to the inactive state (high) to ensure proper system reset. The delay time starts after VDD has risen above VIT. When the supply voltage drops below VIT, the output becomes active (low) again.
The product spectrum is designed for supply voltages of 3.3 V and 5 V. The TPS3619 and TPS3620 are available in an 8-pin MSOP package and are characterized for operation over a temperature range of –40°C to +85°C.
Supply Current of 40 µA (Max)
Battery-Supply Current of 100 nA (Max)
Precision Supply Voltage Monitor 3.3 V, 5 V, Other Options on Request
Backup-Battery Voltage Can Exceed VDD
Power On Reset Generator With Fixed 100-ms Reset Delay Time
Voltage Monitor For Power-Fail or Low-Battery Monitoring
Battery Freshness Seal (TPS3619)
Pin-For-Pin Compatible With MAX819, MAX703, and MAX704