L79xxAC
2 % negative voltage regulators
Features
■
■
■
■
■
Output current to 1.5 A
Output voltages of -5; -8; -12; -15; -24 V
Thermal overload protection
Short circuit protection
Output transition SOA protection
TO-220
D
2
PAK
Description
The L79xxAC series of three-terminal negative
regulators is available in TO-220 and D
2
PAK
packages and several fixed output voltages.
These regulators can provide local on-card
regulation, eliminating the distribution problems
associated with single point regulation;
furthermore, having the same voltage option as
the L78xxA positive standard series, they are
particularly suited for split power supplies. If
adequate heat sinking is provided, they can
deliver over 1.5 A output current.
Although designed primarily as fixed voltage
regulators, these devices can be used with
external components to obtain adjustable
voltages and currents.
Although designed primarily as fixed voltage
regulators, these devices can be used with
external components to obtain adjustable
voltages and currents.
Table 1.
Device summary
Order codes
Part number
TO-220
L7905AC
L7908AC
L7912AC
L7915AC
L7924AC
L7905ACV
L7908ACV
L7912ACV
L7915ACV
L7924ACV
D
2
PAK
L7905ACD2T-TR
L7908ACD2T-TR
L7912ACD2T-TR
Out. Volt.
-5 V
-8 V
-12 V
-15 V
-24 V
December 2007
Rev 8
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www.st.com
22
Contents
L79xxAC
Contents
1
2
3
4
5
6
7
8
Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Application information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
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L79xxAC
Diagram
1
Figure 1.
Diagram
Schematic diagram
3/22
Pin configuration
L79xxAC
2
Figure 2.
Pin configuration
Pin connections (top view)
TO-220
D
2
PAK
4/22
L79xxAC
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
Operating junction temperature range
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
°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
D
2
PAK
3
62.5
TO-220
3
50
Unit
°C/W
°C/W
Table 3.
Symbol
R
thJC
R
thJA
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