Ripple Noise Measurement Conditions

Characteristics, Functions, and Applications

connectorOutput	+	Load
	+
	C1	C2

Output ripple and noise measurement point (20MHz)

C1: 100µF Electrolytic capacitor

C2: 0.1µF Film capacitor

L : 150mm

SERIES OPERATION (TO INCREASE OUTPUT VOLTAGE OR

TO OBTAIN SEPARATE ±OUTPUT)

When the output voltage of a single power supply is insufficient, several power supplies can be connected in series in order to obtain a higher voltage or separate ±outputs.

If power supplies A and B in the illustration below are 5V each, a 10V output can be obtained in this connection. It should be noted that, however, the output current is limited to the lower rated cur- rent value of the power supplies A and B. There is no problem if the voltages of A and B are different from each other.

D1 and D2 in the illustration designate diodes for preventing reverse voltage application. They are provided for preventing inter- nal components of the power supply having the lower rated voltage from being damaged by an applied reverse voltage caused by a short circuit in the load or the like.

Use diodes which meet the following requirements:

Reverse withstanding voltage: Over twice that of the combined output voltage

Forward current: Over twice that of the output current

Forward voltage drop: As small as possible (e.g. Shottkey diode, etc.)

SERIES CONNECTION FOR INCREASING OUTPUT VOLTAGE

Power supply A	+
Power supply A	D1
	–	Load
	(A)∗	Load
Power supply B	+
Power supply B	D2
	–

∗For obtaining separate ±outputs, (A) should be zero voltage.

• All specifications are subject to change without notice.

(18/30)

INSULATION AND WITHSTAND VOLTAGE TESTS

The insulation and withstand voltage tests may cause deteriora- tion. Care must be taken for execution of the tests. The potential must be equal among input, output, and FG (frame ground) termi- nals. It is preferable to use testers that gently start up at the test- ON and automatically discharge charged energy at the test-OFF. Manual discharging after the tests should be through a resistor around 100kΩ to 1MΩ (Do not perform discharging at low imped- ance. It may cause deterioration.)

In any case, take full countermeasures for electric-shock preven- tion.

OTHER CONDITIONS

•Unless conditions are otherwise specified in the specifications or standards, 25°C and rated input-output should be applied.

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