TDK iFA Series manual ON/OFF Control from Input Side

Advance Data Sheet: MaxetaTM iFA Series

FUSE

	+Vin
C1	R1
	-Vin
SW	+ON/OFF
	-ON/OFF

ION/OFF

ON/OFF Control from Input Side

An alternative way to control ON/OFF is from the output side by utilizing AUX output pin of the same module. To do so, the user must supply a switch between the module sense(-) terminal and the –ON/OFF terminal of ON/OFF pins. A 2.5 KΩ, 0.125W resistor is recommended to connect between the module AUX pin and the +ON/OFF terminal. The maximum current sinking capability of the ON/OFF terminal is 5mA or less. The current required to maintain the module ON status must be greater than 1mA.

Other methods such as using an external power source and a transistor are also possible. Please consult the field application engineering department of TDK Innoveta Inc for details.

AUX

R1

-S

Output Voltage Adjustment: The output voltage of the power module is adjustable by the user using an external resistor or by applying external voltage. However, when the output voltage is increased, the input voltage range is limited as shown in the following figure.

Vin Limit for Trim-up

(%Vo,nom)trim	115
	100
	110
	105
Vo,	95

18 19 20 21 22 23 24 25

Vin (V)

To trim the output voltage up, a fixed or variable resistor, Rext1, shall be connected between the Vout(+) pin and the sense(+) pin while the Vout(-) pin and the sense(-) pin should be shorted by a jumper wire as shown below. The trim pin should be left open. The output voltage trim-up rate is approximately 1V / KΩ. To trim the voltage up to 30.8V from 28V, a 2.87KΩ external resistor needs be used.

Rext1
S(+)
Vo(+)
Co	Load

SW

1K

+ON/OFF

-ON/OFF

Vo(-)

S(-)

Trim

ION/OFF

ON/OFF Control from Output Side

Figure Trim up Connection

©2005 TDK Innoveta Inc.		￿ (877) 498-0099
iFA Advance Datasheet	6/6/2005	13/18