RH5RH301A Datasheet, PDF (28/29 Pages) RICOH electronics devices division – PWM STEP-UP DC/DC CONVERTER

• Step-up/Step-down Circuit with Flyback
Trance1:1
Diode
RH5RH ××1A
Lx
OUT
VIN
Vss
VOUT
+
Capacitor
RH5RH
Starter Circuit
(Note) Use a RH5RH××2B,depend on the Output Current.
FIG. 8
*^{The Starter Circuit is necessary for all above circuits.}
1.for Step-up Circuit.
Starter Circuit
VIN side
VOUT side
2.for Step-down and Step-up/Step-down Circuit.
VIN side
Starter Circuit
Tr
RST
VOUT side
ZDST
ZDst 2.5V≤/ZDst≤Designation of Output Voltage
Rst Input Bias Current of ZDst and Tr.
(several kΩ to several hundreds kΩ)
27