Typical Applications
1.2V-25V Adjustable Regulator
Regulator with Trimmable Output Voltage
DS009134-3
Full output current not available at high input-output voltages
DS009134-4
†
C1 = 1 µF solid tantalum or 10 µF aluminum electrolytic required for
stability
*C2 = 1 µF solid tantalum is required only if regulator is more than 4" from
power supply filter capacitor
Trim Procedure:
— If V
OUT
is −23.08V or bigger, cut out R3 (if smaller, don’t cut it out).
— Then if V
OUT
is −22.47V or bigger, cut out R4 (if smaller, don’t).
— Then if V
OUT
is −22.16V or bigger, cut out R5 (if smaller, don’t).
This will trim the output to well within 1% of −22.00 V
DC
, without any of the
expense or trouble of a trim pot (see LB-46). Of course, this technique can
be used at any output voltage level.
3
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