UG:305
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USER GUIDE | UG:305
PI3741-0x-EVAL1
Cool-Power
®
ZVS Switching Regulators Buck-Boost
Evaluation Board
Contents
Page
Introduction
The PI3741‑0x‑EVAL1 evaluation board demonstrates the features and benefits of the Vicor ZVS
Buck‑Boost regulator; pre‑configured for either a 24 or 48V output voltage and rated for up to
150W. Please refer to the corresponding PI3741‑0x‑LGIZ data sheet for all power specifications. The
PI3741‑0x‑EVAL1 evaluation board is used with the following ZVS buck‑boost products:
PI3741‑00‑LGIZ, PI3741‑01‑LGIZ.
The evaluation board provides several options for applying input power (VIN and GND) and output load
(VOUT and GND). The user can solder tab‑style banana jacks or wire, use threaded connectors with
retaining nuts or solder turret pins for clip‑on connections.
The evaluation board comes with all of the PI3741‑0x‑LGIZ’s features accessible to the user. The
current‑monitor function (IMON) is set up to monitor the PI3741‑0x‑LGIZ's output current, sensed across
a 5mΩ resistor. The general purpose amplifier (VDIFF) comes pre‑set with a gain of 2, but can be easily
reconfigured for differential measurements by adding extra 0603 resistors.
The I/O pins are brought out to the right edge of the evaluation board to allow for easy monitoring
or for adding additional circuitry. The status of the PGD pin is indicated by a dual‑colored LED; red
indicating a fault and green indicating no faults. The SYNCO (sync out) and SYNCI (sync in) pins are
accessible to allow for paralleling or for synchronizing to an external clock. Shorting J5 between IMON
and VSP on the board will connect the output of IMON to the positive input of the general purpose
amplifier, allowing for user‑designed signal scaling and conditioning.
A footprint for an external Soft‑Start capacitor (0603) is available to tailor the start‑up profile of the
converter. The error amplifier’s output (EAO) is brought to a pin and in conjunction with the soft‑start
pin can be used for paralleling converters. The error amplifier’s input (EAIN) is not directly connected to
a pin, but connects to the pin EXT_VREF via a 10kΩ series resistor. Applying a DC voltage to this pin will
allow the user to change the regulated output voltage without changing the feedback network.
The board is designed with an edge connector to facilitate testing at the factory, but this connection
can also be used for board evaluation. The PCB is 4‑layer FR‑4 170Tg material with 2oz copper per layer,
ENIG pad finish and a board thickness of 0.062in.