Micro DC-DC Converter Evaluation Board Rev. 1.0
Page 3
+ OUT, –OUT
An electronic or passive load should be connected to +OUT
and –OUT terminals of the Evaluation Board with short
heavy-gauge leads. Most commercially available electronic
l
oads do not have current slew rates capable of fully
exercising the converter. The Evaluation Board can be
connected directly to the application for which the
DC-DC converter is intended. However, the interconnect
impedances between the Evaluation Board and the
application can greatly affect the transient response. For
applications where transient response is critical, the user
should consider mounting the DC-DC converter directly to
the target application PCB. Kelvin connections –OUT(K) and
+OUT(K) can be used only to monitor the output and are
located on the PCB adjacent to the output terminals. The
output can also be monitored by using the scope jack J1.
Secondary Control (SC)
The SC pin can be used to modify the output voltage set
point. This pin can be left open if the nominal output
voltage is desired. Attaching an appropriate value resistor
between the SC pin and the –OUT pin of the converter
will trim the output down. A resistor from +OUT will trim
the output voltage up. See the Maxi, Mini, Micro
Design Guide and Applications Manual or use the
online calculator for trim resistor values at
www.vicorpower.com/powerbench/product-calculators.
Primary Control (PC)
PC can be used to disable the DC-DC converter or can
function as a 6 V auxiliary supply. Common connections
are as follows:
a
. Connecting PC to the –IN will disable the
DC-DC Converter.
b. Connecting a DVM or oscilloscope between PC
(positive) and –IN (negative) will indicate the status of
the converter. This requires that a 10 kΩ pull down
resistor be added from PC to –IN as the PC pin does
not have active pulldown.
Parallel (PR)
The PR pin is used to control load sharing in parallel arrays.
The voltage at this pin pulses at the switching frequency
of the DC-DC converter. It should be left open when
evaluating a single module. The Evaluation Board has a
footprint for the addition of a PR coupling transformer
to create parallel arrays with fully isolated inputs.
For further information on the function and proper use of
module control pins refer to the Maxi, Mini, Micro,
Design Guide and Applications Manual. This is available for
downloading at www.vicorpower.com/dc-dc-converters-
board-mount/maxi-mini-micro-dc-dc-converters.
Input Fusing
Warning: A fuse is required to provide protection
in the event of a module failure. Safety agency
conditions of acceptability require that the module
positive input terminal be fused.
For acceptable input fuses see the Design Requirements
sections of the Maxi, Mini, Micro Design Guide and
Applications Manual. If a 3AG fuse is required use the
fuse holder located on the corner of the Evaluation Board
as shown in Figure 3. A location is also provided for
soldering a PC-Tron fuse in place, see Figure 4.
Figure 4: Fuse installation for PC-TronFigure 3: Fuse installation for 3AG
