R1218N021A Datasheet, PDF (2/21 Pages) RICOH electronics devices division – Step-up DC/DC converter for White LED Backlight

R1218x
BLOCK DIAGRAMS
VFB
R1218xxx1A
VIN
Error Amp
Vref
PWM Comp
RQ
S
OSC
Slope
Compensation
Σ
Shutdown
delay
Chip Enable
UVLO
Switch
Control
Current
Protect
LX
VOUT
OVP
Current
sense
CE
R1218xxx2A
VFB
VIN
Error Amp
Vref
PWM Comp
RQ
S
OSC
Slope
Compensation
Σ
Shutdown
delay
Chip Enable
UVLO
Switch
Control
Current
Protect
GND
LX
VOUT
OVP
Current
sense
CE
GND
2