2001 Fairchild Semiconductor Corporation
www.fairchildsemi.com
Rev. 1.0.4
Features
1A / 5V Output low dropout voltage regulator
TO220 Full-Mold package (4PIN)
Overcurrent protection, Thermal shutdown
Overvoltage protection, Short-Circuit protection
With output disable function
Description
The KA78R05 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 KA78R05 is below 0.5V in full rated
current(1A). This regulator has various function such as
peak current protection, thermal shut down, overvoltage
protection and output disable function.
TO-220F-4L
1. Vin 2. V
O
3. GND 4. Vdis
1
Internal Block Diagram
THERMAL SHUTDOWN
BANDGAP REFERENCE
OVERVOLTAGE
PROTECTION
SOA PROTECTION
SHORTCIRCUIT
PROTECTION
1
4
3
2
Vin
Vdis
Vo
GND
HIGH / LOW
OUTPUT
ON / OFF
Q1
R1
R2
-
+
-
+
1.4V
SHORT-CIRCUIT
KA78R05
Low Dropout Voltage Regulator
KA78R05
2
Absolute Maximum Ratings
Electrical Characteristics
(Vin = 7V, Io = 0.5A, Ta = 25
C, unless otherwise specified)
Note:
1.These parameters, although guaranteed, are not 100% tested in production.
2. Junction -to -case thermal resistance test enviroments.
-. Pneumatic heat sink fixture.
-. Clamping pressure 60psi through 12mm diameter cylinder.
-. Thermal grease applied between PKG and heat sink fixture
Parameter
Symbol
Value
Unit
Remark
Input Voltage
Vin
35
V
-
Disable Voltage
Vdis
35
V
-
Output Current
Io
1.0
A
-
Power Dissipation 1
Pd1
1.5
W
No Heatsink
Power Dissipation 2
Pd2
15
W
With Heatsink
Junction Temperature
Tj
+150
C
-
Operating Temperature
Topr
-20 ~ +80
C
-
Thermal Resistance, Junction-to Case (Note2)
R
jc
4.31
C/W
-
Thermal Resistance, Junction-to-Air (Note2)
R
ja
48.83
C/W
-
Thermal Shutdown Temperature
Ttsd
150
C
-
Parameter
Symbol
Conditions
Min.
Typ.
Max.
Unit
Output Voltage
Vo
-
4.88
5
5.12
V
Load Regulation
Rload
5mA < Io < 1A
-
0.1
2.0
%
Line Regulation
Rline
6V < Vin < 12V
-
0.5
2.5
%
Ripple Rejection Ratio
RR
note1
45
55
-
dB
Dropout Voltage
Vdrop
Io = 1A
-
-
0.5
V
Disable Voltage High
VdisH
Output Active
2.0
-
-
V
Disable Voltage Low
VdisL
Output Disabled
-
-
0.8
V
Disable Bias Current High
IdisH
Vdis = 2.7V
-
-
20
A
Disable Bias Current Low
IdisL
Vdis = 0.4V
-
-
-0.4
mA
Quiescent Current
Iq
Io = 0A
-
-
10
mA
KA78R05
3
Typical Perfomance Characteristics
Figure 1. Output Voltage vs. Input Voltage
Figure 3. Output Voltage vs. Disable Voltage
Figure 5. Quiescent Current vs. Temperature(Tj)
Figure 2. Quiescent Current vs. Input Voltage
Figure 4. Output Voltage vs. Temperature(Tj)
Figure 6. Dropout Voltage vs. Junction Temperature
5
10
15
Input voltage Vin (V)
6
5
4
3
2
1
7
0
0
O
u
t
put
v
o
l
t
ag
e
V
o
(
V
)
RL=
RL=5
8
7
6
5
4
3
0
0
Out
p
ut vol
t
ag
e
V
o
(V
)
3
Disable voltage Vdis (V)
0.5
1.5
2
1
1
2
2.5
10
8
6
4
2
0
Q
u
es
c
e
nt
c
u
r
r
e
n
t
I
q
(
m
A
)
Junction temperature Tj(
o
C)
75
125
0
25
50
100
-25
i
50
40
30
20
10
0
0
Qu
es
ce
nt
cu
r
r
e
n
t
I
q
(
m
A
)
15
Input voltage Vin (V)
5
10
RL= 8
i
5.04
5.02
5.00
5.06
-25
O
u
t
p
u
t
vo
lt
age
V
o
(
V
)
TEMPERATURE Tj(
o
C )
75
125
0
25
50
100
4.96
4.94
4.92
4.98
Junction temperature Tj(
o
C)
125
0.6
0.5
0.4
0.3
0
D
r
opout
vol
t
age
V
d
r
o
p
(
V
)
0.2
0.1
75
0
25
50
100
-25
Io=3A
2.0A
1.0A
0.5A
KA78R05
4
Typical Perfomance Characteristics
(Continued)
Figure 7. Power Dissipation vs. Temperature(Ta)
-25
P
o
w
e
r
dis
s
ip
a
t
io
n P
D
(W
)
TEMPERATURE T
J
(
o
C)
75
125
0
25
50
100
15
10
5
20
0
D
a
Output Current(A)
0
0.5
1.0
Re
l
a
ti
v
e
o
u
t
p
u
t
v
o
l
t
a
g
e
(
%
)
1.5
2.5
2.0
80
60
20
100
0
40
3.0
Output Current(A)
0
0.5
1.0
Output Current(A)
0
0.5
1.0
Re
l
a
ti
v
e
o
u
t
p
u
t
v
o
l
t
a
g
e
(
%
)
1.5
2.5
2.0
80
60
20
100
0
40
3.0
Re
l
a
ti
v
e
o
u
t
p
u
t
v
o
l
t
a
g
e
(
%
)
1.5
2.5
2.0
80
60
20
100
0
40
3.0
Figure 8. Overcurrent Protection Characteristics
(Typical Value)
KA78R05
5
Typical Application
Figure 1. Application Circuit
Ci is required if regulator is located an appreciable distance from power supply filter.
Co improves stability and transient response.(Co > 47
F)
+
+
1
2
3
4
Vin
Vdis
Vo
GND
Disable Signal
KA78R05
6
Mechanical Dimensions
Package
Dimensions in millimeters
TO-220F-4L
KA78R05
7
Mechanical Dimensions
(Continued)
Package
Dimensions in millimeters
TO-220F-4L(Forming)
KA78R05
8
Mechanical Dimensions
(Continued)
Package
Dimensions in millimeters
SPEC NO.
DWG. NO.
5 : 1
SCALE
N/A
TOLERANCE
mm
UNIT
D
TO-220F-4L , SHORT LEAD
TITLE
1. THESE DIMENSIONS DO NOT INCLUDE MOLD PROTRUSION.
2. ( ) IS REFERENCE
3. [ ] IS ASS'Y OUT QUALITY
NOTE
PKG OUTLINE
TO-220F-4L(Short Lead)
KA78R05
9
Ordering Information
Product Number
Package
Operating Temperature
KA78R05TU
TO-220F-4L
-20
C to + 80
C
KA78R05YDTU
TO-220F-4L(Forming)
KA78R05TSTU
TO-220F-4L(Short Lead)
KA78R05
12/18/01 0.0m 001
Stock#DSxxxxxxxx
2001Fairchild Semiconductor Corporation
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which, (a) are intended for surgical implant into the body,
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perform when properly used in accordance with
instructions for use provided in the labeling, can be
reasonably expected to result in a significant injury of the
user.
2. A critical component in any component of a life support
device or system whose failure to perform can be
reasonably expected to cause the failure of the life support
device or system, or to affect its safety or effectiveness.
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PRODUCTS HEREIN TO IMPROVE RELIABILITY, FUNCTION OR DESIGN. FAIRCHILD DOES NOT ASSUME ANY
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