Preliminary
RT9811
Micro-Power Voltage Detectors
General Description
The RT9811 is a micro-power voltage detector with
de-glitched manual reset input supervising the power
supply voltage level for microprocessors (碌P) or
digital systems. It provides internally fixed threshold
levels with 0.1V per step ranging from 1.5V to 5V,
which covers most digital applications. It features low
supply current of 2.5碌A(chǔ).
The RT9811 performs supervisory function by
sending out a reset signal whenever the VDD voltage
falls below a preset threshold level. This reset signal
will last the whole period before VDD recovering.
Once VDD recovered up-crossing the threshold level,
the reset signal will be released after a certain delay
time. A 5% hysteresis splits the rising and falling
threshold levels. To pull reset signal low manually,
just pull the manual reset input (MR) below the
specified V
IL
level.
RT9811 is provided in SOT-25 package.
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Features
Internally Fixed Threshold 1.5V to 5V in 0.1V
Step
鹵
2% Accuracy
Low Supply Current 2.5碌A(chǔ)
碌
No External Components Required
Quick Reset within 20碌S
碌
Built-in Recovery Delay 400mS
100nS Glitch Immunity of Manual Reset Input
Low Functional Supply Voltage 0.9V
Small 4-Pin SOT-25 Package
Pin Configurations
Part Number
RT9811-
(SOT-25)
CB
Pin Configurations
TOP VIEW
5
4
1.
2.
3.
4.
5.
GND
NC
RESET
MR
VDD
Applications
Computers
Controllers
Intelligent Instruments
Critical
碌P
and
碌C
Power Monitoring
Portable/Battery-Powered Equipment
Typical Application Circuit
VDD
碌P
RESET
RT9811
GND
VDD
Ordering Information
RT9811-
Package Type
B : SOT-25
Operating temperature range
C: Commercial standard
Reset Threshold
15 : 1.5V
16 : 1.6V
:
49 : 4.9V
50 : 5.0V
RESET
MR
DS9811-00 June 2001
www.richtek-ic.com.tw
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