USER GUIDE | UG:017
Analog Control 3623 and 4623 ChiP DCMs
Evaluation Board
Arthur Russell
VI Chip Applications Engineering
October 2014
Contents Page
Introduction
Introduction 1
The Analog Control 3623 and 4623 ChiP DCM evaluation boards described in this document are
designed to be used with the DCM family of isolated, DC-DC converters. The 3623 DCM board is used
Contents 3
for the analog control, low input voltage 3623 ChiP products, while the 4623 DCM board is used for
Features 3
the analog control, high input voltage (ofifl ne) 4623 ChiP products.
Board Description 4
The DCM evaluation board can be configured for various enabling and fault monitoring schemes,
as well as to exercise various modes of trimming, depending on the application requirements. The
General Components 4
evaluation board can be used to evaluate DCMs in either a stand-alone configuration, or as an
Test Points Description 6 array of modules.
Schematic, Assembly Drawing
and Bill of Materials 7
Enable options:
Recommended Test
1. On-board mechanical switch (default)
Equipment 14
2. External control
Basic Connections 14
Board Operation Details 14
Trim options:
Trim Control 15
1. Fixed trim operation (default): the TR pin is permitted to float at initial startup.
Fault Monitoring 15
The DCM disables output trimming and the output trim is programmed to the nominal rated V .
OUT
Chassis Ground 16
2. Variable trim operation, on-board variable resistor: The trim pin voltage is ratiometric,
with a rheostat working against a pull-up resistor inside the DCM to VCC.
Paralleling 16
3. Variable trim operation, off-board control: The trim pin voltage is controlled via external
programming control, which is referenced to the IN of each specific DCM in the system.
Fault monitor options:
1. On-board LED: the FT pin drives a visible LED for visual feedback on fault status.
2. On-board optocoupler: the FT pin drives an on-board optocoupler to bring
fault status across the primary-secondary isolation boundary.
UG:017 vicorpower.com Applications Engineering: 800 927.9474 Page 1 IMPORTANT NOTICE:
Hazardous voltages are present on the DCM Evaluation Board under power.
PERSONAL CONTACT WITH LINE VOLTAGE MAY RESULT IN SEVERE INJURY, DISABILITY, OR
DEATH. IMPROPER OR UNSAFE HANDLING OF THIS BOARD MAY RESULT IN SERIOUS INJURY
OR DEATH.
Read the precautions below entirely BEFORE using the DCM Evaluation Board. Do not operate the
evaluation board unless you have the appropriate safety precautions in place on your bench to
guarantee safety.
The list below is not comprehensive and is not a substitute for common sense and
good practice.
nnDuring operation, the power devices and surrounding structures can be operated
safely at high temperatures.
nnRemove power and use caution when connecting and disconnecting test probes
and interface lines to avoid inadvertent short circuits and contact with hot surfaces.
nnNever use a jumper in place of the fuse.
nnWhen testing electronic products always use approved safety glasses. Follow good
laboratory practice and procedures.
nnAvoid creating ground loops when making measurements of the isolated input
or output voltage.
nnCare should be taken to protect the user from accidental contact when
under power.
nnCare should be taken to avoid reversing polarities if connecting to the opposite
(solder) side of the board.
nnThe product evaluation boards described in this document are designed for
general laboratory evaluation, and are not suitable for installation in
end user equipment.
nnRefer to the specific DCM module data sheet for electrical, thermal, and mechanical
product details
UG:017 vicorpower.com Applications Engineering: 800 927.9474 Page 2