PRD48AF480T400A00 Datasheet, PDF (8/9 Pages) Vicor Corporation – PRM-AL Customer Evaluation Boards

6.3.2



Depending upon the chosen initial output voltage determined by the
OS resistors, the amount of available adjustment might be very limited.
Enabling SC adjustment by toggling the SC switch (#3) to the ON
position may result in shut down.
6.3.3 To avoid the situation described in 6.3.2, set the SC trim pot R04

(100 kΩ) to its maximum value prior to enabling the switch.
6.3.4




The data sheet has an equation for calculating the appropriate resistor
value for a trimmed output voltage. This value would be the sum of
fixed resistor R03 (5.11 kΩ) and the trim pot R04. R04 can be set using
the test points provided locally, or the sum set using the SC and SG test
points (Items 3 and 6) when the SC switch is ON.
6.4 Activating Adaptive Loop Regulation and Interconnect Compensation CD.
6.4.1



The CD switch (#4) and the associated fixed resistor R05 (20 Ω) and
trim pot R06 (20 Ω) enable the PRM® Adaptive Loop regulation feature,
which compensates for the VTM® output resistance induced voltage
drop as the load current from the VTM is increased.
6.4.2 This feature is intended to be used with mating VTM-CB discussed in

detail in the next section.
VTM Evaluation Board
The VTM module provides the isolation stage and the output voltage step down. When
paired with the PRM the chip set forms a traditional DC-DC converter. Please refer to
UG:014 for more information on the VTM evaluation board.
Figure 4.
VTM Evaluation Board
UG:003
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