®
RT9742
70mΩ/55mΩ, 3A/2.5A/2A/1.5A/1A/0.5A High-Side Power
Switches with Flag
General Description
Features
70mΩ/55mΩ (typ.) N-MOSFET Switch
Operating Range : 2.7V to 6V
Reverse Blocking Current
Under Voltage Lockout
The RT9742 is a cost-effective, low-voltage, single
N-MOSFET high-side Power Switch IC for USB application.
Low switch-on resistance and low supply current are
realized in this IC.
Deglitched Fault Report (FLG)
Thermal Protection with Fold-back
Over Current Protection
The RT9742 integrates an over-current protection circuit,
a short fold back circuit, a thermal shutdown circuit and
an under-voltage lockout circuit for overall protection.
Besides, a flag output is available to indicate fault
conditions to the local USB controller. Furthermore, the
chip also integrates an embedded delay function to prevent
miss-operation from happening due to inrush-current. The
RT9742 is an ideal solution for USB power supply and
can support flexible applications since it is available in
TSOT-23-5, TSOT-23-5 (FC) and SOT-23-3 package.
Short Circuit Protection
UL Approved−E219878
Nemko Approved-NO109777
Applications
USB Peripherals
Notebook PCs
Pin Configuration
(TOP VIEW)
VIN
EN/EN
VOUT
VIN
VOUT
EN
GND
5
4
5
4
5
4
3
2
3
2
3
2
3
2
VIN
VOUT
VOUT GND VIN
VOUT GND FLG
EN GND FLG
TSOT-23-5 /
TSOT-23-5 (FC)
TSOT-23-5
For RT9742M/V only
TSOT-23-5
For RT9742U only
SOT-23-3
Simplified Application Circuit
USB Controller
Over-Current
Supply Voltage
2.7V to 6V
VIN
FLG
C
IN
RT9742
V
VOUT
Chip Enable
BUS
EN/EN
D+
C
OUT
GND
D-
GND
Data
is a registered trademark of Richtek Technology Corporation.
Copyright 2020 Richtek Technology Corporation. All rights reserved.
©
DS9742-10 January 2020
www.richtek.com
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