3-TERMINAL ADJUSTABLE REGULATOR
SLVS044R – SEPTEMBER 1997 – REVISED APRIL 2007
www.ti.com
APPLICATION INFORMATION (continued)
LM317
+35 V
INPUT
OUTPUT
R1
120
Ω
V
O
ADJUST
−10 V
C1
0.1
µF
R3
680
Ω
R2
3 kΩ
V
O
is calculated as:
V
O
+
V
ref
1
)
R2
)
R3
)
I
Adj
(R2
)
R3) – 10 V
R1
Since I
Adj
typically is 50
µA,
it is negligible in most applications.
Figure 2. 0-V to 30-V Regulator Circuit
LM317
V
I
INPUT
OUTPUT
R1
240
Ω
D1
1N4002
(see Note A)
C3
1
µF
R2
5 kΩ
C2
10
µF
V
O
ADJUST
C1
0.1
µF
NOTE A: D1 discharges C2 if the output is shorted to ground.
Figure 3. Adjustable Regulator Circuit With Improved Ripple Rejection
LM317
V
I
INPUT
OUTPUT
R1
I
limit
+
1.2
R1
ADJUST
Figure 4. Precision Current-Limiter Circuit
8
TI [ TEXAS INSTRUMENTS ]
