Linear Integrated Circuit
CURRENT−MODE PWM CONTROLLER
−
The KA3842A
KA3842AM
are fixe frequency current-mode
PWM controller. They are specially designed for OFF−Line and DC−to−DC converter
applications with minimal external components. These integrated circuits feature a
trimmed oscillator for precise duty cycle control, a temperature compensated reference,
high gain error amplifier, current sensing comparator, and a high current totempole
output ideally suited for driving a power MOSFET.
Protection circuity includes built under−voltage lockout and current limiting.
The
KA3842A,KA3842AM
have UVLO thresholds of 16 V(on) and 10 V (off).
The KA3842A ,KA384AM
can
operate
within 100%
duty cycle
The KA3842A has been proven
in applications
using the same
external components as Motorola's parts,among others .The
KA3842AM
has been optimized for compatibility with Samsung's parts
Many applications can use either
The KA3842A
KA3842AM
have Start-Up Current 0,45 mA
KA3842A or KA3842AM
KA3842A
KA3842AM
PIN CONNECTION
FEATURES
•
•
•
•
Low Start-Up Current
Maximum Duty Cycle
U/V Lockout With Hysteresis
Operating Freguency Up To 500khz
SO-8
DIP-8
ordering
information
Device
KA3842AM
KA3842AMM
KA3842AN
KA3842AMN
Package
SO-8
SO-8
DIP-8
DIP-8
Operating temperature
0 to +70
0
C
"
"
"
BLOCK DIAGRAM
Absolute Maximum Ratings
Characteristic
Supply Voltage
Output Current
Analog Inputs
Error Amp Output Sink Current
Power Dissipation (T
A
=25
0
C)
Symbol
V
CC
I
O
V
I
I
SINK (E.A)
P
O
Value
30
±1
−0.3
to V
CC
10
1
Unit
V
A
V
mA
W
Wing Shing Computer Components Co., (H.K.)Ltd.
Homepage:
http://www.wingshing.com
Tel:(852)2341 9276 Fax:(852)2797 8153
E-mail: wsccltd@hkstar.com
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