Features
■ Output current up to 100 mA
■ Output voltages of 3.3; 5; 6; 8; 9; 10; 12; 15; 18;
24 V
■ Thermal overload protection
■ Short circuit protection
■ No external components are required
■ Available in either ± 4 % (AC) or ± 8 % (C)
selection
L78LxxAB
L78LxxAC - L78LxxC
Positive voltage regulators
TO-92
Description
The L78Lxx series of three-terminal positive
regulators employ internal current limiting and
thermal shutdown, making them essentially
indestructible. If adequate heat-sink is provided,
they can deliver up to 100 mA output current.
They are intended as fixed voltage regulators in a
wide range of applications including local or oncard regulation for elimination of noise and
distribution problems associated with single-point
regulation. In addition, they can be used with
power pass elements to make high-current
voltage regulators. The L78Lxx series used as
Zener diode/resistor combination replacement,
offers an effective output impedance improvement
Table 1. Device summary
L78L33C L78L08AC L78L15C
L78L33AC L78L08AB L78L15AC
L78L33AB L78L09C L78L15AB
L78L05C L78L09AC L78L18C
L78L05AC L78L09AB L78L18AC
L78L05AB L78L10AC L78L24C
of typically two orders of magnitude, along with
lower quiescent current and lower noise.
Part numbers
SO-8
SOT-89
L78L06AC L78L12C L78L24AC
L78L06AB L78L12AC L78L24AB
L78L08C L78L12AB
February 2011 Doc ID 2145 Rev 18 1/30
www.st.com
30
Contents L78LxxAB - L78LxxAC - L78LxxC
Contents
1 Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2 Pin configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3 Maximum ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4 Electrical characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
5 Typical performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
6 Typical application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7 Package mechanical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
8 Order codes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
9 Revision history . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
2/30 Doc ID 2145 Rev 18
L78LxxAB - L78LxxAC - L78LxxC Diagram
1 Diagram
Figure 1. Schematic diagram
Doc ID 2145 Rev 18 3/30
Pin configuration L78LxxAB - L78LxxAC - L78LxxC
2 Pin configuration
Figure 2. Pin connection (top view, bottom view for TO-92)
SO-8
Figure 3. Test circuits
SOT-89
PIN 1 = V
OUT
PIN 2 = GND
PIN 3 = V
IN
TO-92
4/30 Doc ID 2145 Rev 18
L78LxxAB - L78LxxAC - L78LxxC Maximum ratings
3 Maximum ratings
Table 2. Absolute maximum ratings
Symbol Parameter Value Unit
V
= 3.3 to 9 V 30
O
V
I
P
T
STG
T
OP
1. Our SO-8 package used for voltage regulators is modified internally to have pins 2, 3, 6 and 7 electrically communed to the
die attach flag. This particular frame decreases the total thermal resistance of the package and increases its ability to
dissipate power when an appropriate area of copper on the printed circuit board is available for heat-sinking. The external
dimensions are the same as for the standard SO-8.
DC Input voltage
I
Output current 100 mA
O
Power dissipation Internally limited
D
= 12 to 15 V 35
O
V
= 18 to 24 V 40
O
Storage temperature range -65 to 150 °C
for L78L00AC 0 to 150
Operating junction temperature range
for L78L00AB -40 to 125
(1)
VV
mW
°C
Table 3. Thermal data
Symbol Parameter SO-8 TO-92 SOT-89 Unit
R
thJC
R
thJA
1. Considering 6 cm² of copper Board heat-sink.
Thermal resistance junction-case. (max) 20 15 °C/W
Thermal resistance junction-ambient. (max) 55
(1)
200 55
(1)
°C/W
Doc ID 2145 Rev 18 5/30
Electrical characteristics L78LxxAB - L78LxxAC - L78LxxC
4 Electrical characteristics
Refer to the test circuits, TJ = 0 to 125 °C, IO = 40 mA, CI = 0.33 µF, CO = 0.1 µF unless
otherwise specified.
Table 4. Electrical characteristics of L78L33C (VI = 8.3 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
ΔV
Output voltage TJ = 25 °C 3.036 3.3 3.564 V
O
I
= 1 to 40 mA, VI = 5.3 to 20 V 2.97 3.63
Output voltage
O
Line regulation
O
O
= 1 to 70 mA, VI = 8.3 V 2.97 3.63
I
O
V
= 5.3 to 20 V, TJ = 25 °C 150
I
= 6.3 to 20 V, TJ = 25 °C 100
V
I
IO = 1 to 100 mA, TJ = 25 °C 60
ΔV
Load regulation
O
= 1 to 40 mA, TJ = 25 °C 30
I
O
TJ = 25 °C 6 mA
I
Quiescent current
ΔI
d
Quiescent current change
d
= 125 °C 5.5 mA
T
J
I
= 1 to 40 mA 0.2
O
= 6.3 to 20 V 1.5
V
I
eN Output noise voltage B =10 Hz to 100 kHz, T
= 6.3 to 16.3 V, f = 120 Hz
V
SVR Supply voltage rejection
V
Dropout voltage 1.7 V
d
I
= 40 mA, TJ = 25 °C
I
O
= 25 °C 40 µV
J
41 49 dB
V
mV
mV
mA
6/30 Doc ID 2145 Rev 18
L78LxxAB - L78LxxAC - L78LxxC Electrical characteristics
Table 5. Electrical characteristics of L78L05C (VI = 10 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
Output voltage TJ = 25 °C 4.6 5 5.4 V
O
I
= 1 to 40 mA, VI = 7 to 20 V 4.5 5.5
O
Output voltage
O
= 1 to 70 mA, VI = 10 V 4.5 5.5
I
O
VI = 8.5 to 20 V, TJ = 25 °C 200
ΔV
ΔV
Line regulation
O
Load regulation
O
I
Quiescent current
d
= 9 to 20 V, TJ = 25 °C 150
V
I
I
= 1 to 100 mA, TJ = 25 °C 60
O
= 1 to 40 mA, TJ = 25 °C 30
I
O
T
= 25 °C 6 mA
J
= 125 °C 5.5 mA
T
J
IO = 1 to 40 mA 0.2
ΔI
eN Output noise voltage B =10 Hz to 100 kHz, T
SVR Supply voltage rejection
V
Quiescent current change
d
Dropout voltage 1.7 V
d
= 8 to 20 V 1.5
V
I
= 25 °C 40 µV
J
= 9 to 20 V, f = 120 Hz
V
I
IO = 40 mA, TJ = 25 °C
40 49 dB
V
mV
mV
mA
Table 6. Electrical characteristics of L78L08C (VI = 14 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
ΔV
Output voltage TJ = 25 °C 7.36 8 8.64 V
O
I
= 1 to 40 mA, VI = 8.5 to 20 V 7.2 8.8
Output voltage
O
Line regulation
O
O
= 1 to 70 mA, VI = 12 V 7.2 8.8
I
O
V
= 8.5 to 20 V, TJ = 25 °C 200
I
= 9 to 20 V, TJ = 25 °C 150
V
I
IO = 1 to 100 mA, TJ = 25 °C 80
ΔV
ΔI
Load regulation
O
I
Quiescent current
d
Quiescent current change
d
= 1 to 40 mA, TJ = 25 °C 40
I
O
T
= 25 °C 6 mA
J
T
= 125 °C 5.5 mA
J
I
= 1 to 40 mA 0.2
O
= 8 to 20 V 1.5
V
I
eN Output noise voltage B =10 Hz to 100 kHz, T
= 9 to 20 V, f = 120 Hz
V
SVR Supply voltage rejection
V
Dropout voltage 1.7 V
d
I
IO = 40 mA, TJ = 25 °C
= 25 °C 60 µV
J
36 45 dB
V
mV
mV
mA
Doc ID 2145 Rev 18 7/30
Electrical characteristics L78LxxAB - L78LxxAC - L78LxxC
Table 7. Electrical characteristics of L78L09C (VI = 15 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
Output voltage TJ = 25 °C 8.28 9 9.72 V
O
I
= 1 to 40 mA, VI = 11.5 to 23 V 8.1 9.9
O
Output voltage
O
= 1 to 70 mA, VI = 15 V 8.1 9.9
I
O
VI = 11.5 to 23 V, TJ = 25 °C 250
ΔV
ΔV
Line regulation
O
Load regulation
O
I
Quiescent current
d
= 12 to 23 V, TJ = 25 °C 200
V
I
I
= 1 to 100 mA, TJ = 25 °C 80
O
= 1 to 40 mA, TJ = 25 °C 40
I
O
T
= 25 °C 6 mA
J
= 125 °C 5.5 mA
T
J
IO = 1 to 40 mA 0.2
ΔI
eN Output noise voltage B =10 Hz to 100 kHz, T
SVR Supply voltage rejection
V
Quiescent current change
d
Dropout voltage 1.7 V
d
= 12 to 23 V 1.5
V
I
= 25 °C 70 µV
J
= 12 to 23 V, f = 120 Hz
V
I
IO = 40 mA, TJ = 25 °C
36 44 dB
V
mV
mV
mA
Table 8. Electrical characteristics of L78L10C (VI = 16 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
ΔV
ΔV
ΔI
eN Output noise voltage B =10Hz to 100kHz, T
SVR Supply voltage rejection
V
Output voltage TJ = 25 °C 9.2 10 10.8 V
O
I
= 1 to 40 mA, VI = 12.5 to 23 V 9 11
O
Output voltage
O
= 1 to 70 mA, VI = 16 V 9 11
I
O
VI = 12.5 to 23 V, TJ = 25 °C 230
Line regulation
O
Load regulation
O
I
Quiescent current
d
= 13 to 23 V, TJ = 25 °C 170
V
I
I
= 1 to 100 mA, TJ = 25 °C 80
O
= 1 to 40 mA, TJ = 25 °C 40
I
O
T
= 25 °C 6 mA
J
= 125 °C 5.5 mA
T
J
IO = 1 to 40 mA 0.1
Quiescent current change
d
= 13 to 23 V 1.5
V
I
V
= 14 to 23 V, f = 120Hz
I
IO = 40 mA, TJ = 25 °C
Dropout voltage 1.7 V
d
= 25 °C 60 µV
J
37 45 dB
V
mV
mV
mA
8/30 Doc ID 2145 Rev 18
L78LxxAB - L78LxxAC - L78LxxC Electrical characteristics
Table 9. Electrical characteristics of L78L12C (VI = 19 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
Output voltage TJ = 25 °C 11.1 12 12.9 V
O
I
= 1 to 40 mA, VI = 14.5 to 27 V 10.8 13.2
O
Output voltage
O
= 1 to 70 mA, VI = 19 V 10.8 13.2
I
O
VI = 14.5 to 27 V, TJ = 25 °C 250
ΔV
ΔV
Line regulation
O
Load regulation
O
I
Quiescent current
d
= 16 to 27 V, TJ = 25 °C 200
V
I
I
= 1 to 100 mA, TJ = 25 °C 100
O
= 1 to 40 mA, TJ = 25 °C 50
I
O
T
= 25 °C 6.5 mA
J
= 125 °C 6 mA
T
J
IO = 1 to 40 mA 0.2
ΔI
eN Output noise voltage B =10 Hz to 100 kHz, T
SVR Supply voltage rejection
V
Quiescent current change
d
Dropout voltage 1.7 V
d
= 16 to 27 V 1.5
V
I
= 25 °C 80 µV
J
= 15 to 25 V, f = 120 Hz
V
I
IO = 40 mA, TJ = 25 °C
36 42 dB
V
mV
mV
mA
Table 10. Electrical characteristics of L78L15C (VI = 23 V)
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
V
ΔV
Output voltage TJ = 25 °C 13.8 15 16.2 V
O
I
= 1 to 40 mA, VI = 17.5 to 30 V 13.5 16.5
Output voltage
O
Line regulation
O
O
= 1 to 70 mA, VI = 23 V 13.5 16.5
I
O
V
= 17.5 to 30 V, TJ = 25 °C 300
I
= 20 to 30 V, TJ = 25 °C 250
V
I
IO = 1 to 100 mA, TJ = 25 °C 150
ΔV
ΔI
Load regulation
O
I
Quiescent current
d
Quiescent current change
d
= 1 to 40 mA, TJ = 25 °C 75
I
O
T
= 25 °C 6.5 mA
J
T
= 125 °C 6 mA
J
I
= 1 to 40 mA 0.2
O
= 20 to 30 V 1.5
V
I
eN Output noise voltage B =10 Hz to 100 kHz, T
= 18.5 to 28.5 V, f = 120 Hz
V
SVR Supply voltage rejection
V
Dropout voltage 1.7 V
d
I
IO = 40 mA, TJ = 25 °C
= 25 °C 90 µV
J
33 39 dB
V
mV
mV
mA
Doc ID 2145 Rev 18 9/30
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