GAMW2V040 – 4

WWW.GALAXYPWR.COM

Part No. 02-GAM-04 Rev. 1.0 – 042805

Galaxy Power Inc.

155 Flanders Road

Westborough, MA 01581

Telephone: 508-870-9775

Fax: 508-870-9796

e-mail: info@galaxypwr.com

Output Over Voltage Protection:

The output voltage is constantly monitored by the

microprocessor with a redundant secondary-side

measurement circuit that both shuts down the duty

cycle and triggers the microprocessor to shut down.

If the output voltage exceeds the over-voltage specifi-

cation, the microprocessor will latch the converter off.

To turn the converter on requires either cycling the

ON/OFF pin or power to the converter. This ad-

vanced feature prevents the converter from damaging

the load if there is a converter failure or application

error. If non-latching is required, consult factory.

Thermal Shutdown:

The printed circuit board temperature is measured

using a semiconductor sensor. If the maximum rated

temperature is exceeded, the converter is latched off.

To re-enable the converter requires cycling the ON/

OFF pin or power to the converter. If non-latching is

required, consult factory.

Control Options:

As the behavior of the circuit is determined by

firmware in the microcontroller, specific customer

requirements such as

• non-latching thermal protection

• custom valid input voltage range

• controlled delay from initiating an ON/OFF signal

for power sequencing

can be accomplished with no change to hardware.

The standard behavior was chosen based on system

design experience but we understand that customers

often have their own requirements.

Please consult Galaxy Power for your special needs.

Remote Sense:

The output voltage is regulated at the point where

the sense pins connect to the power output pins.

Total sense compensation should not exceed 0.4V or

10% of Vout, whichever is greater.

Safety:

An external input fuse must always be used to meet

these safety requirements.

External Output Trimming

Application Notes

Increase in Output Voltage (%)

1000

100

10

0

1

23456

7

8

9

10

2.0V Trim-up

+ Sense

Trim

– Sense

Decrease in Output Voltage (%)

1000

100

10

0

1

23456

7

8

9

10

Trim-down

Trim-up

Trim-down

2 (100+∆%)

–

(100+2∆%)

5.11kΩ

1.225∆%

∆%

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}

Trim:

To trim the output voltage higher, connect the

required trim resistor from the Trim pin to the

+Sense pin. To trim the output voltage lower, con-

nect the required trim resistor from the Trim pin to

the –Sense pin.

100

– 2

5.11kΩ

∆%

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