Fairchild Semiconductor KA78RM33D, KA78RM33 Datasheet

KA78RM33

Low Dropout Voltage Regulator

www.fairchildsemi.com

Features

• 0.5A / 3.3V Output low dropout vo l tag e regula t o r

• Low dropout voltage (Max. 0.6V)

• Over current protection, Thermal shutdown

• SOA prote ction, Short circuit protection

Internal Block Digram

Description

The KA78RM33 is a low-dropout voltage regulator suitable
for various electronic equipment. It provide constant voltage
power source with surface mount type package (D-PAK).
dropout volta ge of KA78RM33 is be low 0.6V in full rated
current(0.5A). This regulator has various function such as
over current protection, thermal shut down and SOA (Safe
operating Area) protection.

D-PAK

1

TO-220

1

1. Vin 2. GND 3. Vout

1Vin

Current
Generator

Bandgap
Reference

2

3

GND

©2001 Fairchild Semiconductor Corporation

Thermal
Shutdown
Protection

Short Circuit
Protection

Error
Amp.

SOA
Protection

Output
Drive

Q1

R1

R2

3

Vout

Rev. 1.0.1

KA78RM33

Absolute Maximum Ratings

Parameter Symbol Value Unit Remark

Input Voltage
Output Current I
Thermal Resistance Junction-Air R
Power Dissipation

Vin

O

θJA

Pd

20 V -

0.5 Α -

110 °C/W No Heatsink

Interally limited − -
Junction Temperature Tj 150 °C-
Operating Temperature T

OPR

-25~ + 125 °C-

Electrical Characteristics

(Vin = 5V, IO= 0.25A, Ta = 25

°C , unless otherwise specified

Parameter Symbol Conditions Min. Typ. Max. Unit

Output Voltage V
Load Regulation Rl
Line Regulation R

Out
Oad
line

Ripple Rejection Ratio RR f=120Hz, Vin=5V ±0.5Vrms 55 - - dB
Dropout Voltage V
Quiescent Current Ι
Peak Current I
Output Noise Voltage V
Temperature Coefficient of Output

Voltage

∆V

drop

q

PK

OUT

n

/∆T

)

IO =10mA 3.22 3.3 3.38 V
5mA < IO < 0.5A - 2 20 mV

4.3V <Vin < 16V - 2 20 mV

IO=0.5A - - 0.6 V
IO = 0A - 5 10 mA
Vin = 5V 0.5 1 - A
10Hz < f < 100KHz - 50 - uVrms

-25°C < Tj < 125°C
I

= 100mA

O

--0.2-mV/°C

2