LM317
3-TERMINAL ADJUSTABLE REGULATOR
SLVS044H – SEPTEMBER 1997 – REVISED DECEMBER 2001
APPLICATION INFORMATION
LM317
VI
INPUT
OUTPUT
R1
240
Ω
Cin (Note A)
0.1
µF
IAdj
Vref = 1.25 V
CO (Note B)
1.0
µF
VO
ADJUST
R2
NOTES: A. Cin is not required if the regulator is close enough to the power-supply filter.
B. CO improves transient response, but is not needed for stability.
Vout is calculated as:
V
out
+
V
ref
1
Since IAdj is typically 50
µA,
it is negligible in most applications.
)
R2
)
(I
R1
Adj
R2)
Figure 1. Adjustable Voltage Regulator
LM317
+35 V
INPUT
OUTPUT
R1
120
Ω
VO
ADJUST
–10 V
C1
0.1
µF
R3
680
Ω
R2
3 kΩ
Vout is calculated as:
V
out
+
V
ref
1
)
)
R2 R1 R3
)
I
Adj
(R2
)
R3) – 10 V
Since IAdj is typically 50
µA,
it is negligible in most applications.
Figure 2. 0-V to 30-V Regulator Circuit
4
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
TI [ TEXAS INSTRUMENTS ]
