RT9801A/B
User Programmable Micro-Power Voltage Detectors
General Description
The RT9801A/B is a micro-power voltage detector
supervising the power supply voltage level for
microprocessors (μP) or digital systems. It provides user
programmable threshold levels with 0.1V step ranging
from 1.5V to 5V, which covers most digital applications. It
features low supply current of 3μA. Selection of V
TH
is
easily achieved through 3 pins connected to GND, V
DD
or
floating for different threshold voltage settings. Two versions
of threshold voltages, 1.5V to 4V and 2.5V to 5V, which
are programmed in factory are offered by customer
demands.
The RT9801A/B performs supervisory function by sending
out a reset signal whenever the V
DD
voltage falls below a
preset threshold level. This reset signal will last the whole
period before V
DD
recovering. Reset signal will release after
V
DD
is recovered and last for the whole period of Reset
Active Time-out period.
RT9801A/B is N-Channel, open-drain output and provided
in SOT-23-6 package.
Features
User Programmable Threshold 1.5V to 5V in 0.1V
Step with
±
3% Accuracy
Low Supply Current 3μA
μ
Quick Reset within 20μs
μ
Built-in Recovery Delay 200ms
Low Functional Supply Voltage 0.9V
Small SOT-23-6 Package
RoHS Compliant and 100% Lead (Pb)-Free
Applications
Computers
Controllers
Intelligent Instruments
Critical
μP
and
μC
Power Monitoring
Portable/Battery-Powered Equipment
Pin Configurations
(TOP VIEW)
VSET1 VSET2 VDD
6
1
5
2
4
3
Ordering Information
RT9801
Package Type
E : SOT-23-6
Operating Temperature Range
P : Pb Free with Commercial Standard
G : Green (Halogen Free with Commer-
cial Standard)
Reset Threshold
A : 2.5V to 5V
B : 1.5V to 4V
VSET0 GND RESET
SOT-23-6
Note
: There is no pin1 indicator on top mark for SOT-23-6
type, and pin 1 will be lower left pin when reading top mark
from left to right.
Note :
RichTek Pb-free and Green products are :
RoHS compliant and compatible with the current require-
ments of IPC/JEDEC J-STD-020.
Suitable for use in SnPb or Pb-free soldering processes.
100%matte tin (Sn) plating.
Typical Application Circuit
μP
VDD
GND
RESET
VSET0
VSET1
RT9801
GND
VSET2
RESET
Pull Up
VDD
Marking Information
For marking information, contact our sales representative
directly or through a RichTek distributor located in your
area, otherwise visit our website for detail.
DS9801AB-11 March 2007
RT9801 V
TH
= 2.5V in this example
www.richtek.com
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