RH5RH
APPLICATION CIRCUITS
• 12V Step-up Circuit
Inductor
Diode
VOUT
ZD:6.8V
RH5RH502B
Cb
Rb
OUT
EXT
+
Capacitor
VIN
Vss
RZD
Tr
Starter Circuit
(Note) When the Output Current is small or the Output Voltage is unstable,use the Rzd for flowing the bias current through the Zener diode ZD.
FIG. 6
• Step-down Circuit
Inductor
VOUT
PNP
Tr
Diode
RH5RH××1A
OUT
Rb2
Lx
VIN
Rb1
+
Vss
Capacitor
Starter Circuit
(Note) When the LX pin Voltage is over the rating at the time PNP Tr is OFF,use a RH5RH××2B and drive the PNP Tr. by the external NPN Tr.
FIG. 7
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