Definition of Terms
(Continued)
Quiescent Current:
That part of the positive input current
that does not contribute to the positive load current. The
regulator ground lead current.
Ripple Rejection:
The ratio of the peak-to-peak input ripple
voltage to the peak-to-peak output ripple voltage.
Temperature Stability of V
O
:
The percentage change in
output voltage for a thermal variation from room temperature
to either temperature extreme.
Typical Applications
5V to 20V Adjustable Regulator
DS008823-3
Note:
Using 1k for R1 will ensure that the input bias current error of the adjust pin will be negligible. Do not bypass R1 or R2. This will lead to instabilities.
* Required if regulator is located far from power supply filter.
*
* C
OUT
must be at least 22 µF to maintain stability. May be increased without bound to maintain regulation during transients. Locate as close as possible to the
regulator. This capacitor must be rated over the same operating temperature range as the regulator and the ESR is critical; see curve.
1A Switch
DS008823-6
**
* To assure shutdown, select Resistor R3 to guarantee at least 300 µA of pull-up current when S1 is open. (Assume 2V at the ON/OFF pin.)
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