Datasheet R1525x for Consumer Applications (Ricoh) - 9

R1525x
NO. EA-520-190109
TECHNICAL NOTES Phase Compensation
Phase compensation is provided to secure stable operation even when the load current is varied. For this purpose, make sure to use 0.1 μF or more of a capacitor (COUT). In case of using a tantalum type capacitor and the ESR (Equivalent Series Resistance) value of the capacitor is large, the output might be unstable. Evaluate the circuit including consideration of frequency characteristics. Connect 0.1 μF or more of a capacitor (CIN) between VDD and GND, and as close as possible to the pins.
PCB Layout
For SOT-23-5 package type, wire the following GND pins together: No. 1 and No. 2 For SOT-89-5 package type, wire the following GND pins together: No. 2 and No. 4. For HSOP-6J package type, wire the following GND pins together: No. 2, No. 4, and No. 5.
Input Transient / Load Transient vs. Output Capacity (COUT)
R1525x performs a stable operation by using 0.1 µF of ceramic capacitor as the output capacitor. However, the variation of output voltage may not meet the demand of the system when input voltage and load current vary. In such cases, the variation of output voltage can be minimized significantly by using 10 µF or higher ceramic capacitor. When using an electrolytic capacitor for the output line, place the electrolytic capacitor outer side of the ceramic capacitor arranged close to the IC.
<Input Transient Response> <Load Transient Response> R1525x033B R1525x033B
16 30 14 20 ) 12 ) Input Voltage ) Output Current (V 1mA 10 ) (V tr=tf=1μs tr=tf=0.5μs A UT 10 (V UT 0 m O IN O 8 rent ( 3.5 6 tage V tage V 3.5 tage V ol ol ol Output Voltage Cur V 3.3 V V 3.4 3.1 Output Voltage 3.3 utput utput Input 2.9 utput O O 3.2 O 2.7 - 3.1 2.5 - 3.0 -1 0 1 2 3 4 5 6 7 -100 0 100 200 300 400 500 600 700 800 Time (ms) Time (us) 9