1 Features
• Power-on reset generator with adjustable delay
time: 1.25 ms to 10 s
• Very low quiescent current: 2.4 μA typical
• High threshold accuracy: 0.5% typical
• Fixed threshold voltages for standard voltage rails
from 0.9 V to 5 V and adjustable voltage down to
0.4 V are available
• Manual reset ( MR) input
• Open-drain RESET output
• Temperature range: –40°C to 125°C
• Small SOT-23 and 2-mm × 2-mm WSON
packages

2 Applications
• DSP or microcontroller applications
• Notebook and desktop computers
• PDAs and hand-held products
• Portable and battery-powered products
• FPGA and ASIC applications

3 Description
The TPS3808 family of microprocessor supervisory
circuits monitors system voltages from 0.4 V to
5 V, asserting an open-drain RESET signal when
the SENSE voltage drops below a preset threshold
or when the manual reset ( MR) pin drops to a
logic low. The RESET output remains low for the
user-adjustable delay time after the SENSE voltage
and manual reset ( MR) return above the respective
thresholds.
The TPS3808 device uses a precision reference to
achieve 0.5% threshold accuracy for VIT ≤ 3.3 V. The
reset delay time can be set to 20 ms by disconnecting
the CT pin, 300 ms by connecting the CT pin to VDD
using a resistor, or can be user-adjusted between
1.25 ms and 10 s by connecting the CT pin to an
external capacitor. The TPS3808 device has a very
low typical quiescent current of 2.4 μA, so it is wellsuited
to battery-powered applications. It is available
in the SOT-23 and 2-mm × 2-mm WSON packages,
and is fully specified over a temperature range of –
40°C to 125°C (TJ).