Datasheet

LM317M
http://onsemi.com
11
Figure 21. Adjustable Current Limiter Figure 22. 5 V Electronic Shutdown Regulator
Figure 23. Slow Turn−On Regulator Figure 24. Current Regulator
V
ref
+25V
V
in
LM317M
V
out
R
1
V
O
1.25k
Adjust
I
O
D2
1N914
1N5314
R
2
500
* To provide current limiting of I
O

to the system ground, the source of
the current limiting diode must be tied to
 a negative voltage below −7.25 V.
R
2
≥
V
ref
R
1
=
V
SS
*
D1
1N914
V
O
< P
OV
+ 1.25 V + V
SS
I
Lmin
− I
P
< I
O
< 500 mA − I
P
As shown O < I
O
< 495 mA
+
10F
V
in
V
out
240
1N4001
LM317M
Adjust
MPS2907
R
2
50k
V
in
D
1
1N4002
V
out
120
Adjust
720
+
1.0F
MPS2222
1.0k
TTL
Control
LM317M
Minimum V
out
= 1.25 V
D
1
protects the device during an input short circuit.
LM317M
V
in
R
1
R
2
Adjust
I
Adj
I
out
5.0 mA < I
out
< 100 mA
V
out
I
outmax
=
V
ref
+ I
Adj

1.25 V
R
1
+ R
2
V
out
V
out
V
in
I
DSS
I
Omax
+ I
DSS
R
1
+ R
2
40
50
60
70
80
90
100
0
0.4
0.8
1.2
1.6
2.0
2.4
010203025155.0
L, LENGTH OF COPPER (mm)
P
D(max)
for T
A
= 50°C
Minimum
Size Pad
L
L
Free Air
Mounted
Vertically
R

JA
2.0 oz. Copper
Figure 25. DPAK Thermal Resistance and Maximum
Power Dissipation versus PCB Copper Length
Figure 26. SOT−223 Thermal Resistance and Maximum
Power Dissipation versus PCB Copper Length
40
80
120
160
200
240
280
0.35
0.42
0.50
0.63
0.83
1.25
2.50
010203025155.0
L, LENGTH OF COPPER (mm)
P
D(max)
for T
A
= 50°C
Minimum
Size Pad
L
L
Free Air
Mounted
Vertically
R

JA
2.0 oz. Copper
R , THERMAL RESISTANCE,
JAθ
JUNCTION−TO−AIR ( C/W)°