XRP7665
3A 18V Synchronous Step-Down Converter
1
XRP7665’ s
constitute a zero. The frequency of this
E r r o r
A mp l i f i e r
a n d
=
2 ×
×
compensating zero is given by:
1
=
where Rload is the output load resistance.
2 ×
×
The uncompensated regulator has a constant
gain up to its pole frequency, beyond which
the gain decreases at -20dB/decade. The zero
arising from the output capacitor’s ESR is
inconsequential if ceramic COUT is used. This
simplifies the compensation. The RC and CC,
which are placed between the output of
For the typical application circuit, RC=6.8k Ω
and CC=3.9nF provide a satisfactory
compensation. Please contact EXAR if you
need assistance with the compensation of your
particular circuit.
TYPICAL APPLICATIONS
Fig. 18: XRP7665 Typical Application Diagram - 12V to 3.3V Conversion
© 2013 Exar Corporation
10/12
Rev. 2.0.1
EXAR [ EXAR CORPORATION ]
