KA3501 Datasheet, PDF (1/6 Pages) Fairchild Semiconductor – PC SMPS Supervisory IC

KA3501
PC SMPS Supervisory IC
www.fairchildsemi.com
Features
• Complete House Keeping Circuit
• Few External Components
• Positive Voltage Protection
• Negative Voltage Protection
• High Current Drive Output for SCR
• Precision Voltage Reference for 5V/12V Outputs
• Power Good Signal Generator with Hysteresis
Description
The KA3501 is complete housekeeping circuits for use in the
secondary side of SMPS(Switched Mode Power Supply).
This IC(Integrated Circuit) contains a precision voltage
reference, protection circuits and a power good signal
generator. It also has a high current drive output for use in
conjunction with an external "crowbar" SCR. The reference
voltage is trimmed to ±2% for correct output voltages(+5V/
+12V) and power good signal generator is to monitor the
voltage level of power good supply for safe operation in a
microprocessor circuit. Using the KA3501 requires few
external components to accomplish a complete
housekeeping circuit for SMPS(Switched Mode Power
Supply). The KA3501 is available in an 14-pin DIP.
14-DIP
Internal Block Diagram
4 V_CC1(+5V)
1
VCC 7
8 Vin1
Vin2
5
GATE
6
Feedback
14
2
Vref
Positive
Voltage
Protection
Negative
Voltage
Protection
+2.5V
REFERENCE
VOLTAGE
START UP
INTERNAL
BIAS
VCC2(+12V) 3
1 Vcont 13 GND
+5V
Detecting
lchg
COMP
VCC
Detecting
COMP
9 _Td
10 Timing
©2002 Fairchild Semiconductor Corporation
11
PG
12
Ve
Rev. 1.0.2