R1234D Datasheet, PDF (9/26 Pages) RICOH electronics devices division – PWM/VFM Step-Down DC/DC CONVERTER with Synchronous Rectifier

TEST CIRCUITS
1 ^VIN
Lx 8
R1234D
Series
3 ^VDD
CE 4
7 ^AGND 5 VOUT
A
2 ^{PGND MODE} 6
R1234D
1 ^VIN
Lx 8
R1234D
Series
3 ^VDD
CE 4
7 ^AGND 5 VOUT
2 ^{PGND MODE} 6
OSCILLOSCOPE
Test Circuit for Input Current and Leakage Current Test Circuit for Input Voltage and UVLO voltage
1 ^VIN
Lx 8
R1234D
Series
3 ^VDD
CE 4
7 ^AGND 5 VOUT
OSCILLOSCOPE
VOUT
L
10µF
2 ^{PGND MODE} 6
Test Circuit for Output Voltage, Oscillator Frequency, Soft-Starting Time
1 ^VIN
Lx 8
R1234D
Series
A
3 ^VDD
CE 4
7 ^AGND 5 VOUT
2 ^{PGND MODE} 6
1 ^VIN
Lx 8
R1234D
Series
3 ^VDD
CE 4
OSCILLOSCOPE
A
7 ^AGND 5 VOUT
2 ^{PGND MODE} 6
Test Circuit for Supply Current and Standby Current
Test Circuit for ON resistance of LX,
Limit Voltage, Delay Time of Protection Circuit
The bypass capacitor between power supply and GND is a ceramic capacitor 10µF.
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