Precision High Voltage Regulator
906430
Q1, Q2: NSD134 or similar
C1, C2: 1μF, 200V mylar**
*Heat sink
**Mylar is a registered trademark of DuPont Co.
R1, R2 = matched resistors with good TC tracking
Tracking Regulator
Regulator With Trimmable Output Voltage
906432
Trim Procedure:
—If VOUT is 23.08V or higher, cut out R3 (if lower, don't cut it out).
—Then if VOUT is 22.47V or higher, cut out R4 (if lower, don't).
—Then if VOUT is 22.16V or higher, cut out R5 (if lower, don't).
This will trim the output to well within ±1% of 22.00 VDC, 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.
906431
A1 = LM301A, LM307, or LF13741 only
13
www.national.com