
Semiconductor Components Industries, LLC, 2005
October, 2005 Rev. 7
1
Publication Order Number:
CS5112/D
CS5112
1.4 A Switching Regulator
with 5.0 V, 100 mA Linear
Regulator with Watchdog,
RESET and ENABLE
The CS5112 is a dual output power supply integrated circuit. It
contains a 5.0 V
±
2%, 100 mA linear regulator, a watchdog timer, a
linear output voltage monitor to provide a Power On Reset (POR) and a
1.4 A current mode PWM switching regulator.
The 5.0 V linear regulator is comprised of an error amplifier,
reference, and supervisory functions. It has low internal supply current
consumption and provides 1.2 V (typical) dropout voltage at maximum
load current.
The watchdog timer circuitry monitors an input signal (WDI) from
the microprocessor. It responds to the falling edge of this watchdog
signal. If a correct watchdog signal is not received within the externally
programmable time, a reset signal is issued.
The externally programmable active reset circuit operates correctly
for an output voltage (V
LIN
) as low as 1.0 V. During power up, or if the
output voltage shifts below the regulation limit, RESET toggles low and
remains low for the duration of the delay after proper output voltage
regulation is restored. Additionally a reset pulse is issued if the correct
watchdog is not received within the programmed time. Reset pulses
continue until the correct watchdog signal is received. The reset pulse
width and frequency, as well as the Power On Reset delay, are set by one
external RC network.
The current mode PWM switching regulator is comprised of an error
amplifier with selectable feedback inputs, a current sense amplifier, an
adjustable oscillator, and a 1.4 A output power switch with
antisaturation control. The switching regulator can be configured in a
variety of topologies.
The CS5112 is load dump capable and has protection circuitry which
includes current limit on the linear and switcher outputs, and an
overtemperature limiter.
Features
Linear Regulator
5.0 V
±
2% @ 100 mA
Switching Regulator
1.4 A Peak Internal Switch
120 kHz Maximum Switching Frequency
5.0 V to 26 V Operating Supply Range
Smart Functions
Watchdog
RESET
ENABLE
Protection
Overtemperature
Current Limit
Internally Fused Leads in a SOIC Package
PbFree Packages are Available*
*For additional information on our PbFree strategy and soldering details, please
download the ON Semiconductor Soldering and Mounting Techniques
Reference Manual, SOLDERRM/D.
SOIC24
DWF SUFFIX
CASE 751E
1
24
MARKING DIAGRAM
1
CS5112
AWLYYWWG
24
PIN CONNECTIONS
GND
RESET
C
Delay
WDI
GND
V
FB1
V
FB2
GND
GND
GND
GND
GND
GND
I
BIAS
V
V
LIN
NC
V
REG
NC
ENABLE
V
IN
1
24
C
OSC
COMP
SELECT
Device
Package
Shipping
ORDERING INFORMATION
CS5112YDWF24
SOIC24
30 Units/Rail
CS5112YDWFR24
SOIC24 1000/Tape & Reel
CS5112 = Device Code
A
= Assembly Location
WL
= Wafer Lot
YY
= Year
WW
= Work Week
G
= PbFree Package
For information on tape and reel specifications,
including part orientation and tape sizes, please
refer to our Tape and Reel Packaging Specifications
Brochure, BRD8011/D.
CS5112YDWFR24G
SOIC24
(PbFree)
1000/Tape & Reel
CS5112YDWF24G
SOIC24
(PbFree)
30 Units/Rail
http://onsemi.com