www.fairchildsemi.com
KA78R12
Low Dropout Voltage Regulator
Features
• • • • • 1A / 12V Output low dropout voltage re...
www.fairchildsemi.com
KA78R12
Low Dropout
Voltage Regulator
Features
1A / 12V Output low dropout
voltage regulator TO220 Full-Mold package (4PIN) Overcurrent protection, Thermal shutdown Over
voltage protection, Short-Circuit protection With output disable function
Description
The KA78R12 is a low-dropout
voltage regulator suitable for various electronic equipments. It provides constant
voltage power source with TO-220 4 lead full mold package. Dropout
voltage of KA78R12 is below 0.5V in full rated current(1A). This regulator has various function such as peak current protection, thermal shut down, over
voltage protection and output disable function.
TO-220F-4L
1
1. Vin 2. Vo 3. GND 4. Vdis
Internal Block Diagram
Q1
Vin
1
2
Vo
THERMAL SHUTDOWN
OVER
VOLTAGE PROTECTION
BANDGAP REFERENCE
+ R1
SOA PROTECTION HIGH / LOW Vdis 4 + OUTPUT ON / OFF
R2 1.4V
SHORT-CIRCUIT SHORTCIRCUIT
PROTECTION
3 GND
Rev. 1.0.1
©2001 Fairchild Semiconductor Corporation
KA78R12
Absolute Maximum Ratings
Parameter Input
Voltage Disable
Voltage Output Current Power Dissipation 1 Power Dissipation 2 Junction Temperature Operating Temperature Symbol Vin Vdis Io Pd1 Pd2 Tj Topr Value 35 35 1.0 1.5 15 +150 -20 ~ +80 Unit V V A W W °C °C Remark No Heatsink With Heatsink -
Electrical Characteristics
(Vin =15V, Io = 0.5A, Ta = 25 °C , unless otherwise specified) Parameter Output
Voltage Load Regulation Line Regulation Ripple Rejection Ratio Dropout
Voltage Disable
Voltage High Disable...