R1221N RICOH electronics devices division, R1221N Datasheet - Page 2

• Manufacturer Part Number: R1221N
• Description: Step-down DC/DC Converter with Voltage Detector
• Manufacturer: RICOH electronics devices division

n BLOCK DIAGRAM
Rev. 1.11
VD
V
EXT
n SELECTION GUIDE
IN
Code
OUT
a
b
c
function, and the taping type for the ICs can be selected at the user’s request.
In the R1221N Series, the output voltage, the detector threshold, the oscillator frequency, the optional
The selection can be made by designating the part number as shown below;
12345
R1221NXXXX-TR
Setting Output Voltage(V
Stepwise setting with a step of 0.1V in the range of 1.5V to 5.0V is possible.
Setting Detector Threshold(-V
Stepwise setting with a step of 0.1V in the range of 1.2V to 4.5V is possible.
A:3.0V
Designation of Oscillator Frequency and Optional Function
A:300kHz, with a PWM/VFM alternative circuit, Latch-type protection
B:500kHz, with a PWM/VFM alternative circuit, Latch-type protection
C:300kHz, without a PWM/VFM alternative circuit, Latch-type protection
D:500kHz, without a PWM/VFM alternative circuit, Latch-type protection
E:300kHz, with a PWM/VFM alternative circuit, Reset-type protection
F:500kHz, with a PWM/VFM alternative circuit, Reset-type protection
G:300kHz, without a PWM/VFM alternative circuit, Reset-type protection
H:500kHz, without a PWM/VFM alternative circuit, Reset-type protection
PWM/VFM
CONTROL
- - -
a b c
GND
OSC
OUT
Protection
Soft Start
):
DET
)
Vref
Vref
Contents
- 2 -
Chip Enable
CE
V
OUT