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KA7500C
SMPS Controller
Features
• Internal Regulator Provides a Stable 5V Reference Supply
Trimmed to
±1%
Accuracy.
• Uncommitted Output TR for 200mA Sink or Source
Current
• Output Control for Push-Pull or Single-Ended Operation
• Variable Duty Cycle by Dead Time Control (Pin 4)
Complete PWM Control Circuit
• On-Chip Oscillator With Master or Slave Operation
• Internal Circuit Prohibits Double Pulse at Either Output
Description
The KA7500C is used for the control circuit of the pulse
width modulation switching regulator. The KA7500C
consists of 5V reference voltage circuit, two error amplifiers,
flip flop, an output control circuit, a PWM comparator, a
dead time comparator and an oscillator. This device can be
operated in the switching frequency of 1kHz to 300kHz. The
precision of voltage reference (Vref) is improved up to
±1%
with trimming. This provides a better output voltage
regulation. The operating temperature range is
-25°C ~ +85°C.
16-DIP
16-SOP
1
1
Internal Block Diagram
OUTPUT CONTROL
13
R
T
C
T
6
OSCILLATOR
5
D
Q
9
E1
8
C1
11 C2
DEAD 4
TIME
CONTROL
CK
1.2V
Q
10 E2
PWM
COMP
EA(+) 1
EA(-)
2
5V
12 V
CC
+
_ 1
0.7MA
2
7 GND
BAND GAP
REFERENCE
14 V
REF
EA(+) 16
EA(-) 15
+
_
3
COMP INPUT
Rev. 1.0.1
©2003 Fairchild Semiconductor Corporation
FAIRCHILD [ FAIRCHILD SEMICONDUCTOR ]
