Ricoh R5C841 - Manual (Page 52)

R5C841 PCI-CardBus/IEEE 1394/SD Card/Memory Stick/xD/ExpressCard Data Sheet
12345  2004 R EV .1.10 4-27
4.24 Internal Regulator
The R5C841 has an internal regulator, which converts the single 3.3V power into the power for
the internal core logic. REGEN# signal enables/disables an internal regulator. The following is the
recommended circuit diagram.
R5C841
0.01uF 0.1uF 0.01uF 10uF
0.01uF 0.01uF 0.47uF 0.47uF
0 ohm
open
JP
short
from Regulator
(1.8V)
Regulator Disable Mode
VCC_RIN
VCC_ROUT
REGEN#
R5C841
0.01uF 0.1uF 0.01uF 10uF
0.01uF 0.01uF 0.47uF 0.47uF
open
100k ohm
JP
open
from Regulator
(3.3V)
Regulator Enable Mode
VCC_RIN
VCC_ROUT
REGEN#