1 Features
• 3-pin SOT-23 package
• Supply current of 9 μA (typical)
• Precision supply voltage monitor
2.5 V, 3 V, 3.3 V, 5 V
• Pin-for-pin compatible with MAX 809
• Temperature range: –40°C to +85°C

2 Applications
• Factory automation
• Wireless speakers
• Motor drives
• Servers
• Appliances
• Electricity meters
• Building automation

3 Description
The TPS3809 family of supervisory circuits provides
circuit initialization and timing supervision, primarily
for DSPs and processor-based systems. The newer
TLV809E device is an alternative with the same pins,
functions and electrical parameters.
During power-on, RESET is asserted when the supply
voltage VDD becomes higher than 1.1 V. Thereafter,
the supervisory circuit monitors VDD and keeps
RESET 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, td(typ) =
200 ms, starts after VDD has risen above the threshold
voltage VIT. When the supply voltage drops below the
threshold voltage VIT, the output becomes active (low)
again. No external components are required. All the
devices of this family have a fixed sense-threshold
voltage VIT set by an internal voltage divider.
The product spectrum is designed for supply voltages
of 2.5 V, 3 V, 3.3 V, and 5 V. The circuits are available
in a 3-pin SOT-23. The TPS3809 devices are
characterized for operation over a temperature range
of –40°C to 85°C.