1FEATURES
• Supply Current of 40 mA (Max)
• Battery-Supply Current of 100 nA (Max)
• Precision Supply-Voltage Monitor 3.3 V, 5 V,
and 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-to-Pin Compatible With MAX819, MAX703,
and MAX704
• 8-Pin Mini Small-Outline Package (MSOP)
Package

APPLICATIONS
• Fax Machines
• Set-Top Boxes
• Advanced Voice-Mail Systems
• Portable Battery-Powered Equipment
• Computer Equipment
• Advanced Modems
• Automotive Systems
• Portable Long-Time Monitoring Equipment
• Point-of-Sale Equipment

SUPPORTS DEFENSE, AEROSPACE,
AND MEDICAL APPLICATIONS
• Controlled Baseline
• One Assembly/Test Site
• One Fabrication Site
• Available in Military (–55°C/125°C)
Temperature Range(1)
• Extended Product Life Cycle
• Extended Product-Change Notification
• Product Traceability

DESCRIPTION
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 –55°C to 125°C.