R1234D Datasheet, PDF (16/26 Pages) RICOH electronics devices division – PWM/VFM Step-Down DC/DC CONVERTER with Synchronous Rectifier

R1234D
TYPICAL CHARACTERISTICS
1) Output Voltage vs. Output Current
R1234D181A
1.90
R1234D181B
1.90
1.85
1.85
1.80
1.75
1.70
1
VIN=3.3V PWM
VIN=3.3V VFM
VIN=5.0V PWM
VIN=5.0V VFM
10
100
Output Current IOUT(mA)
1000
2) Efficiency vs. Output Current
R1234D181A
100
90
80
70
60
50
40
30
20
10
0
1
VIN=3.3V PWM
VIN=3.3V VFM
VIN=5.0V PWM
VIN=5.0V VFM
10
100
Output Current IOUT(mA)
1000
3) Output Waveform (COUT=10µF, tantalum, PWM)
R1234D181A
0.06
VIN=5V, IOUT=200mA
ESR=400mΩ
0.04
0.02
0
-0.02
-0.04
-0.06
-0.08
0 1 2 3 4 5 6 7 8 9 10
Time t(µs)
1.80
1.75
1.70
1
VIN=3.3V PWM
VIN=3.3V VFM
VIN=5.0V PWM
VIN=5.0V VFM
10
100
Output Current IOUT(mA)
1000
100
90
80
70
60
50
40
30
20
10
0
1
R1234D181B
VIN=3.3V PWM
VIN=3.3V VFM
VIN=5.0V PWM
VIN=5.0V VFM
10
100
Output Current IOUT(mA)
1000
R1234D181B
0.05
VIN=5V, IOUT=10mA
ESR=400mΩ
0.04
0.03
0.02
0.01
0
-0.01
-0.02
-0.03
-0.04
0 1 2 3 4 5 6 7 8 9 10
Time t(µs)
16