CS5651
CS5651
High Performance Dual Channel
Current Mode Controller with ENABLE
Description
The CS5651 is a high performance,
fixed frequency, dual current mode
controller specifically designed for
Off-Line and DC to DC converter
applications. It offers the designer a
cost effective solution with minimal
external components. This integrat-
ed circuit features a unique oscilla-
tor for precise duty cycle limit and
frequency control, a temperature
compensated reference, two high
gain error amplifiers, two current
sensing comparators, and two high
current totem pole outputs ideally
suited for driving power MOSFETs.
One of the outputs, V
OUT2
is switch-
able via the ENABLE
2
pin.
Also included are protective fea-
tures consisting of input and refer-
ence undervoltage lockouts, each
with hysteresis; cycle-by-cycle cur-
rent limiting; and a latch for single
pulse metering of each output.
The CS5651 is pin compatible with
the MC34065H.
Features
s
Oscillator has Precise
Duty Cycle
Limit and Frequency
Control
s
500kHz Current Mode
Operation
s
Automatic Feed Forward
Compensation
s
Separate Latching PWMs
for Cycle-By-Cycle
Current Limiting
s
Internally Trimmed
Reference with
Undervoltage Lockout
s
Switchable Second
Output
s
Two High Current Totem
Pole Outputs
s
Input Undervoltage
Lockout with Hysteresis
Block Diagram
V
CC
V
REF
5.0V Ref
V
CC
Undervoltage
Lockout
V
REF
Undervoltage
Lockout
SYNC
C
T
R
T
Latching
PWM 1
Oscillator
V
OUT1
+
Sense
1
Package Options
16L PDIP & SO Wide
V
FB1
-
Error
Amp 1
COMP
1
ENABLE
2
Latching
PWM 2
V
OUT2
SYNC
1
C
T
2
R
T
3
16
15
14
13
12
11
10
9
V
CC
V
REF
ENABLE
2
V
FB2
COMP
2
Sense
2
V
OUT2
Pwr Gnd
V
FB2
+
-
Error
Amp 2
COMP
2
Sense
2
V
FB1
4
COMP
1
5
SENSE
1
6
V
OUT1
7
Gnd
Pwr Gnd
Gnd
8
Cherry Semiconductor Corporation
2000 South County Trail, East Greenwich, RI 02818
Tel: (401)885-3600 Fax: (401)885-5786
Email: info@cherry-semi.com
Web Site: www.cherry-semi.com
Rev. 3/9/99
1
A
®
Company
CHERRY [ CHERRY SEMICONDUCTOR CORPORATION ]
