Advancing the
Power Curve
®
Page 1 www.synqor.com | QMS#065-0007299 | Rev. A | 03/31/21 | Advancing the Power Curve -
®
EVAL-1000041
Evaluation Board for MCOTS-C-270-xx-HE or
MCOTS-C-270-xx-FE Converters
Summary
SynQor has developed the EVAL-1000041, an evaluation board to
facilitate testing of our MCOTS-C-270-XX-HE and MCOTS-F-270-P-QT or
MCOTS-C-270-xx-FE converter and MCOTS-F-270-P-HT EMI filter.
Introduction
This application note is a guide to the features, schematic, component placement, and BOM for this evaluation
board. The applicable converter modules are
MCOTS-C-270-xx-HE and MCOTS-F-270-P-QT or MCOTS-C-270-xx-FE
converter and MCOTS-F-270-P-HT EMI filter.
Contents
Section 1 – Converter Description ....................................... 2
Section 2 – Evaluation Board Configuration ............................... 2
Section 3 – Evaluation Board Block Diagram .............................. 2
Section 4 – Input and Output Connections ............................... 3
Section 5 – Switches, Test Points and BNC Connectors ..................... 3
Section 6 – Schematic ................................................. 4
Section 7 – Component Placement ...................................... 5
Section 7 – Basic Operation Instructions ................................. 5
Section 8 – Basic Operating Instructions ................................. 6
Appendix A – Bill of Materials (BOM) ..................................... 7
Required Components ................................................. 8
This evaluation board and schematic are intended for demonstration purposes only and no guarantees are made
for standards compliance.
Shock Warning: There are areas of this evaluation board that have exposed access to hazardous high voltage
levels. Exercise caution to avoid contact with those voltages. Also note that the evaluation board may retain high
voltage temporarily after input power has been removed. Exercise caution when handling.
Application of Input Power: Never apply input power to a convertor with a switch closure, such as a knife
switch or circuit breaker. That type of action applies input voltage with an uncontrolled very high rate of rise (dV/
dt) that could be damaging to the convertor and to external components before the convertor. Instead, apply input
voltage with a controlled rate of rise. Also ensure input voltage is off before inserting or removing a convertor
module from the evaluation board.
Thermal Considerations: When testing EMI lters and converters on an evaluation board, ensure adequate
cooling. Apply cooling air with a fan blowing across the EMI lter and the converter or across the heatsinks
attached to the EMI lter and converter. Monitor the EMI lter and converter temperatures to ensure they don’t
exceed the maximum rated per the datasheets specications.
Isolation Warning: Circuitry on this evaluation board is both isolated and non-isolated with respect to the inputs
on J1. This requires great care in making connections and taking measurements. As such, take great care before
taking any measurement with equipment that may make a connection to ground. Use isolated differential probes
or clamp on style current probes to avoid these issues. The circuits that are isolated from the DC line input can
use a regular grounded scope probe to take measurements.
Application Note EVAL-1000041
Advancing the
Power Curve
®
Page 2 www.synqor.com | QMS#065-0007299 | Rev. A | 03/31/21 | Advancing the Power Curve -
Section 1 – Converter Description
The MCOTS-C-270-xx-HE and MCOTS-C-270-xx-FE Modules are high power, high efciency DC-DC
converters. They operate from a DC (155 V - 425 V) input and generate an isolated DC output. The output
voltages of both modules have droop characteristics. The output voltage and max deliverable current can be
set with a simple resistor or voltage source. Both units have Sync In, Sync Out, Battle Short, Ishare, and Serial
communications capabilities.
Both units have two stages. The input DC stage (155 Vdc - 425 Vdc) steps the input down to a midbus voltage.
This input stage also provides isolation between the input and the output of the unit. The midbus voltage is
adjusted in the second stage to the desired regulated output by means of the unit either a bucking or boosting.
Section 2 – Evaluation Board Conguration
This evaluation board can be used for either MCOTS-C-270-xx-HE or MCOTS-C-270-xx-FE families. Careful
consideration of the input lter current rating need to be taken into account selecting lter and converter modules.
The MCOTS-F-270-P-QT lter should only be used with the MCOTS-C-270-xx-HE. The MCOTS-F-270-P-HT
has appropriate current rating capability for either the –HE or –FE products.
Another major difference is that the MCOTS-C-270-xx-FE family has an isolated On/Off circuitry. This means
that the MCOTS-C-270-xx-FE requires an external power source to disable the output via SW1. In the case of
the MCOTS-C-270-xx-FE, make sure the JMP1 is not populated and +5 V must be connected between +5 V test
point and On/Off- test point for the enable switch (SW1) to turn the unit off.
For the MCOTS-C-270-xx-HE, JMP1 must be populated with SynQor part number 707-0000030. No voltage is
needed between +5 V and On/Off-. The enable switch (SW1) will turn the unit on and off.
Section 3 – Evaluation Board Block Diagram
-
On/Off
Sync Out
Sync In
-
Vin
+Vin
+On/Off
Vin+
Vin-
Vout+
Vout-
Riset
Cin
5V
+Vout
-
Vout
Vset
Ishare
Battle Short
Serial Out
Vsense+
Serial In
Vsense
-
Iset
Rset
Iset
External
Input
Filter
Note 1: An Input Stability calculation will need to be performed to ensure proper damping of the system. Use the SynQor application
notes “Guidelines for Testing SynQor DC-DC Converters” and “Input System Instability” to cover the topics of properly testing and
implementing the DC-DC converters as a load when using this evaluation board.