Datasheet

Electrical characteristics L78xx, L78xxC, L78xxAB, L78xxAC
26/57 DocID2143 Rev 31
Refer to the test circuits, T
J
= 0 to 125 °C, V
I
= 28 V, I
O
= 500 mA, C
I
= 0.33 µF, C
O
= 0.1 µF
unless otherwise specified.
Table 21. Electrical characteristics of L7820C
Symbol Parameter Test conditions Min. Typ. Max. Unit
V
O
Output voltage T
J
= 25°C 19.2 20 20.8 V
V
O
Output voltage I
O
= 5 mA to 1 A, V
I
= 23 to 33 V 19 20 21 V
V
O
Output voltage I
O
= 1 A, V
I
= 33 to 35 V, T
J
= 25°C 19 20 21 V
V
O
(1)
Line regulation
V
I
= 22.5 to 35 V, T
J
= 25°C 400
mV
V
I
= 26 to 32 V, T
J
= 25°C 200
V
O
(1)
Load regulation
I
O
= 5 mA to 1.5 A, T
J
= 25°C 400
mV
I
O
= 250 to 750 mA, T
J
= 25°C 200
I
d
Quiescent current T
J
= 25°C 8 mA
I
d
Quiescent current change
I
O
= 5 mA to 1 A 0.5
mA
V
I
= 23 to 35 V 1
V
O
/T Output voltage drift I
O
= 5 mA -1 mV/°C
eN Output noise voltage B = 10 Hz to 100 kHz, T
J
= 25°C 150 µV/V
O
SVR Supply voltage rejection V
I
= 24 to 35 V, f = 120 Hz 52 dB
V
d
Dropout voltage I
O
= 1 A, T
J
= 25°C 2 V
R
O
Output resistance f = 1 kHz 24 m
I
sc
Short circuit current V
I
= 35 V, T
J
= 25°C 0.18 A
I
scp
Short circuit peak current T
J
= 25°C 2.1 A
1. Load and line regulation are specified at constant junction temperature. Changes in V
O
due to heating effects must be
taken into account separately. Pulse testing with low duty cycle is used.