KA7552A Datasheet, PDF (1/6 Pages) Fairchild Semiconductor – SMPS Controller

KA7552A/KA7553A
SMPS Controller
www.fairchildsemi.com
Features
• Built-in drive circuits for direct connection power
MOSFET (lO = ±1.5A)
• Wide operating frequency range (5kHz ~ 600kHz)
• Pulse by pulse over current limiting
• Over load protection
• On/off control by external trigger
• Internal UVLO
• Low standby current (typ. 90uA)
• Soft start circuit
Description
The KA7552A/KA7553A are switching power control IC
for wide operating frequency range. The internal circuits
include pulse by pulse current limiting, protection, on/off
control by external trigger, low standby current, soft start,
and high current totempole output for driving a POWER
MOSFET. Maximum duty of the KA7552A is 70% and the
KA7553A is 46%. When duty is maximum, the input
threshold voltage of pin2 & pin8 are not same in KA7552A
and KA7553A.
8-DIP
1
Internal Block Diagram
BIAS
OFF
(4V)
4.3K
2.8V
+
-
CS
8
0.56 ~ 0.42V
+
_
+
7V
-
CT RT
7
1
10uA
OSC
UVLO
3.6V
2.4V
1.9V
+
-
-
- _PWM
0.24V _{_}
+
O.C.P
R
Q
S
2
3
FB
IS(+)
©2004 Fairchild Semiconductor Corporation
VCC
6
5
OUTPUT
4
GND
Rev. 1.0.2