Table of Contents
Advertisement
KA3842B/43B
CURRENT MODE PWM CONTROLLER
•OPTIMIZED FOR OFF-LINE AND DC TO DC CONVERTERS
•LOW START-UP CURRENT(<1mA)
• AUTOMATIC FEED FORWARD COMPENSATION
• PULSE-BY-PULSE CURRENT LIMITING
• ENHANCED LOAD RESPONSE CHARACTERISTICS
• DOUBLE PULSE SUPPRESSION
• HIGH CURRENT TOTEM POLE OUTPUT
• INTERNALLY TRIMMED BANDGAP REFERENCE
• 500kHz OPERATION
• LOW Ro ERROR AMP
PIN CONNECTIONS
Comp
1
V
2
FB
Isense
3
R /
C
4
T
T
BLOCK DIAGRAM
V
rel
8
2.5V
R1
4
C1
Voltage
feedback
input
2
Output/
compensation
1
V
8
REF
Vcc
7
Output
6
GROUND
5
Internal
R
bias
R
3.6 V
Oscillator
+
1.0 mA
2R
Error
R
amplifier
Ground
Reference
regulator
Vcc
UVLO
Vref
UVLO
S
Q
10 V
R
+
Current sense
comparator
5
KA3842
--31--
Minidip
Vcc
7
36 V
+
Vc
7
Output
6
Power ground
5
Current sense
PWM
Input
latch
3
Vcc
Vin
Q
1
R
5
Advertisement
Table of Contents
