© Semiconductor Components Industries, LLC, 2006
September, 2006 − Rev. 6
1 Publication Order Number:
NCP346/D
NCP346
Overvoltage Protection IC
The NCP346 Overvoltage Protection circuit (OVP) protects
sensitive electronic circuitry from overvoltage transients and power
supply faults when used in conjunction with an external P−channel
FET. The device is designed to sense an overvoltage condition and
quickly disconnect the input voltage supply from the load before any
damage can occur. The OVP consists of a precise voltage reference, a
comparator with hysteresis, control logic, and a MOSFET gate driver.
The OVP is designed on a robust BiCMOS process and is intended to
withstand voltage transients up to 30 V.
The device is optimized for applications that have an external
AC/DC adapter or car accessory charger to power the product and/or
recharge the internal batteries. The nominal overvoltage thresholds are
4.45 and 5.5 V and can be adjusted upward with a resistor divider
between the V
CC
, IN, and GND pins. It is suitable for single cell
Li−Ion applications as well as 3/4 cell NiCD/NiMH applications.
Features
• Overvoltage Turn−Off Time of Less Than 1.0 msec
• Accurate Voltage Threshold of 4.45 V and 5.5 V (Nominal)
• CNTRL Input Compatible with 1.8 V Logic Levels
• These are Pb−Free Devices
Typical Applications
• Cellular Phones
• Digital Cameras
• Portable Computers and PDAs
• Portable CD and other Consumer Electronics
−
+
OUT
IN
V
ref
GND CNTRL
+
V
CC
Logic
FET
Driver
LOAD
AC/DC Adapter or
Accessory Charger
C1
Schottky
Diode
Microprocessor port
P−CH
Figure 1. Simplified Application Diagram
NCP346
Note: This device contains 89 active transistors
(optional)
(optional)
THIN SOT−23−5
SN SUFFIX
CASE 483
PIN CONNECTIONS &
MARKING DIAGRAM
Device Package Shipping
†
ORDERING INFORMATION
NCP346SN1T1G
SOT−23−5
(Pb−Free)
3000 / Tape & Ree
(7 inch Reel)
xxx = SQZ for NCP346SN1
= SRD for NCP346SN2
A = Asembly Location
Y = Year
W = Work Week
G = Pb−Free Package
(Note: Microdot may be in either location
NCP346SN2T1G
1
5
†For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specification
Brochure, BRD8011/D.
http://onsemi.com
1
3
IN
OUT
2
GND
CNTRL
4
V
CC
5
(Top View)
xxxAYWG
G