L78MxxAB
L78MxxAC
Precision 500 mA regulators
Features
■
■
■
■
■
■
■
Output current to 0.5 A
Output voltages of 5; 6; 8; 9; 10; 12; 15; 18;
24 V
Thermal overload protection
Short circuit protection
Output transition SOA protection
± 2 % Output voltage tolerance
Guaranteed in extended temperature range
with external components to obtain adjustable
voltage and currents.
TO-220
DPAK
Description
The L78MxxAB series of three-terminal positive
regulators is available in TO-220 and DPAK
packages and with several fixed output voltages,
making it useful in a wide range of applications.
These regulators can provide local on-card
regulation eliminating the distribution problems
associated with single point regulation. Each type
employs internal current limiting, thermal shut-
down and safe area protection, making it
essentially indestructible. If adequate heat sinking
is provided, they can deliver over 0.5 A output
current. Although designed primarily as fixed
voltage regulators, these devices can be used
Table 1.
Device summary
Part number
L78M05AB
L78M05AC
L78M06AB
L78M08AB
L78M08AC
L78M09AB
L78M10AB
L78M12AB
L78M12AC
L78M15AB
L78M24AB
L78M24AC
February 2008
Rev 6
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www.st.com
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Contents
L78MxxAB - L78MxxAC
Contents
1
2
3
4
5
6
7
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Test circuits
............................................... 6
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Typical performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Applications information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
7.1
Design considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
8
9
10
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Order codes
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
2/29
L78MxxAB - L78MxxAC
Maximum ratings
3
Table 2.
Symbol
V
I
I
O
P
D
T
STG
T
OP
Maximum ratings
Absolute maximum ratings
Parameter
DC input voltage
Output current
Power dissipation
Storage temperature range
for L78M00AC
Operating junction temperature range
for L78M00AB
-40 to 125
for V
O
= 5 to 18V
for V
O
= 20, 24V
Value
35
V
40
Internally limited
Internally limited
-65 to 150
0 to 125
°C
mA
mW
°C
Unit
Note:
Absolute maximum ratings are those values beyond which damage to the device may occur.
Functional operation under these condition is not implied
Thermal data
Parameter
Thermal resistance junction-case
Thermal resistance junction-ambient
TO-220
3
50
DPAK
8
100
Unit
°C/W
°C/W
Table 3.
Symbol
R
thJC
R
thJA
Figure 4.
Application circuit
5/29
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