LM317L
Typical Applications
(Continued)
Precision High Voltage Regulator
DS009064-30
Q1, Q2: NSD134 or similar
C1, C2: 1µF, 200V mylar
**
*
Heat sink
**
Mylar is a registered trademark of DuPont Co.
Tracking Regulator
Regulator With Trimmable Output Voltage
DS009064-32
Trim Procedure:
— If V
OUT
is 23.08V or higher, cut out R3 (if lower, don’t cut it out).
— Then if V
OUT
is 22.47V or higher, cut out R4 (if lower, don’t).
— Then if V
OUT
is 22.16V or higher, cut out R5 (if lower, don’t).
This will trim the output to well within
±
1% of 22.00 V
DC
, without any of
the expense or uncertainty of a trim pot (see LB-46). Of course, this
technique can be used at any output voltage level.
DS009064-31
A1 = LM301A, LM307, or LF13741 only
R1, R2 = matched resistors with good TC tracking
13
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