Datasheet

IFX27001
Application Information
Data Sheet 17 Rev. 1.01, 2009-10-19
For the variable regulator IFX27001TFV, a minimum load current of 5 mA is necessary in order to keep the output
voltage regulated. If the application does not assure this minimum load requirement, the output voltage divider
should be dimensioned sufficiently
low-ohmic: R
1
≤ 240 Ω.
For the variable voltage type an additional decoupling a capacitor
C
ADJ
at the adjust pin improves the ripple
rejection ratios. Placing
C
ADJ
requires an increased output capacitance of C
Q
≥22 µF.
Output
The output current limitation is reduced as a function of the input voltage for high input voltages above 25 V.
The IFX27001 requires a 10 µF output capacitor with 0.1 Ω ≤ ESR ≤ 10 Ω for the stability of the regulation loop.
At the input of the regulator a capacitor is necessary for compensation of line influences. A series diode should be
used to eliminate negative voltages from the input. As a minimum, a 100 nF ceramic input capacitor should be
used. If the regulator is used in an environment with long input lines, an input capacitance of 10 µF is
recommended.