CALIFORNIA MICRO DEVICES
CMPWR160
USB Peripheral Power Management
Features
• 3.3V regulated output up to 500mA
• Quiescent current 35µA (typical)
• Shutdown mode current 7µA (typical)
• 30ms active LOW Power-On Reset (POR) pulse
• Thermal overload protection
• Foldback current limiting protection
• Reverse-current protection
• 8 pin SOIC power package
Applications
• Bus-powered USB peripherals
• Self-powered USB peripherals
• Portable/battery-powered devices
• Critical power monitoring, hot-insertion devices
The SmartOR
TM
CMPWR160 combines a Low Dropout
Regulator (LDO) with a Power-On Reset (POR) pulse
generator, and is intended for Universal Serial Bus
(USB) peripherals. To meet the specification require-
ments of both USB 1.0 and USB 2.0, the CMPWR160
draws a very low quiescent current (35µA), and delivers
up to 500mA of load current at a fixed 3.3V output.
The POR pulse (active LOW) has a typical duration of
30ms after the output has exceeded and stabilized
above 2.9V. Thus a new POR pulse is developed each
time the regulator power is interrupted and restored,
which occurs often on USB buses when cables are
connected (or disconnected) by the user. It is not
necessary to have a V
CC
supply for POR to operate,
allowing the CMPWR160 to work in Wired-ORed power
systems.
When V
CC
is powered down, the device will automatically
enter reverse-current protection mode and maintain
isolation between V
OUT
and V
CC
. This is useful for applica-
tions that can use power from the USB port in addition to
internal batteries or an AC adapter supply (Wired-ORed
power systems). In the event of V
CC
collapsing below
V
OUT
, the device will automatically enter shutdown mode
and fully isolate the V
CC
power source from the output.
A ShutDown input (SD ) forces the regulator to be
powered down on demand. While in shutdown mode the
POR circuitry will remain active, making the device
suitable for systems which contain backup or alternative
power sources.
The CMPWR160 is available in an 8-pin SOIC thermally
enhanced package, ideal for applications where space
is tight.
Block Diagram
Top View
V
CC
SD
POR
V
OUT
1
2
3
4
8
7
6
5
GND
GND
GND
GND
GND
V
REF
3.3V
V
CC
SD
+
–
SD
V
OUT
3.3V/500mA
+
30ms
CMPWR160
8 LEAD SOIC
POR
–
Pin Diagram
2.9V
Simplified Electrical Schematic
Standard Part Ordering Information
Package
Pin
8
Style
Power SOIC
Tubes
CMPWR160SA/T
Ordering Part Number
Tape & Reel
CMPWR160SA/R
Part Marking
CMPWR160SA
C1571000
©2000 California Micro Devices Corp. All rights reserved. SmartOR™ is a trademark of California Micro Devices Corporation.
215 Topaz Street, Milpitas, California 95035
12/5/2000
Tel: (408) 263-3214
Fax: (408) 263-7846
www.calmicro.com
1
CALMIRCO [ CALIFORNIA MICRO DEVICES CORP ]
