UG:003

vicorpower.com

Applications Engineering: 800 927.9474

Page 5

2.0

Hook Up

2.1

Connect the power supply +Out lead to the +In terminal of the Customer

Evaluation Board.

2.2

Connect the power supply –Out lead to the –In terminal of the Customer

Evaluation Board.

2.3

A high quality, low-noise power supply should be connected to these locations

2.4

Connect a lead between the +Out of the Customer Evaluation Board and +In

of the load.

2.5

Connect a lead between the –Out of the Customer Evaluation Board and –In

of the load.

2.6

Connections to these locations should be with short heavy gauge leads.

3.0

Verify Connections

4.0

Test Sequence

4.1

4.2

Assure that the DC supply is set to 0 Vdc prior to turning the unit on.

4.3

Confirm that the switch bank is configured as shown in the silk screen on the board.

4.4

Turn on the DC supply.

4.5

Make sure the DC load is set to constant current and at 0 A prior to turning

on the load.

4.6

Turn on the DC load.

4.7

Connect an oscilloscope to the test point provided to monitor output voltage. Many

types of scope probes may be directly connected to these points if the probe is

equipped with a removable plastic sheath. Be careful to avoid creating ground loops

when making measurements of this voltage and the input voltage. It is recommended

that the measurements be made separately. Shorting the -input and -output of the PRM

will defeat the PRM current limit feature as the current shunt is in this path.

4.8

Turn on a fan if desired.

4.9

Raise the DC input voltage to the nominal value indicated on the data sheet.

4.10

Verify no load operation by raising and lowering the input voltage through the entire

input voltage range. The output voltage should remain constant within the tolerance

indicated in the data sheet.

4.11

Re-establish the nominal input voltage.

4.12

Slowly increase the load current to full load while monitoring the output voltage. The

output voltage should remain within the limits specified in the appropriate PRM data

sheet.

4.13

Return the load current to 0 A and decrease the input voltage to low line.

4.14

Repeat step 4.12. Depending upon the supply used and the source impedance it may

be necessary to adjust the input voltage to keep the input to the PRM at low line.

4.15

Return the load current to 0 A and increase the input voltage to high line.

4.16

Repeat step 4.12.

5.0

You have now verified the functionality of the PRM over the entire line and load

operating range.

6.0

Deviating from Nominal Settings

This board has provisions, as described in the Board Overview section, to adjust the

configuration of the PRM about the nominal values. The data sheet for the PRM has equations

and curves for determining the required resistor values needed for specific conditions.

Applications requiring output voltages other than the nominal setting will need to have the

new value set via the trim pots and respective switches. Reference Items 4 and 5 of the Board

Overview and the schematic shown in Figure 2.

6.1

Adjust the PRM Output Voltage Set Point

6.1.1

Make sure that the power is removed from the unit prior to making adjustment.

6.1.2

Using a DMM (set to measure resistance), probe between SG (Item 3) and the pad

labeled OS located next to the 5 k

Ω trim pot R08.