1 Introduction
This user's guide presents a typical laboratory setup used with this EVM.
CAUTION
Do not use this EVM for isolation voltage tests even though the isolated power transformer has
galvanic isolation protection of up to 2500 V. This EVM is designed for the evaluation of device
operating parameters only. If a high voltage (greater than 36 V) or a high load current (greater than
500 mA) is applied anywhere in the circuit, the EVM could be damaged.
Exceeding the specified input voltage range and applying loads outside the specified output range may cause
unexpected operation and irreversible damage to the EVM. If there is uncertainty as to the input voltage range,
power specifications, or about using a configuration that is or is not described in this user guide, please contact a
TI field representative or create a post on
2 Overview
The SN6507 evaluation module allows users to evaluate the performance and features of the SN6507 push-pull
isolation transformer driver in an isolated power supply application. This includes a transformer, rectifier circuit,
and an optional low-dropout (LDO) voltage regulator. The power supply input and isolated output is separated by
the isolation transformer which can be de-soldered and replaced with other push-pull transformers in 6-pin and
8-pin packages that fit on the PCB’s T1 footprint.
Isolated power supplies help block high voltages and prevent noise currents from entering isolated grounds and
interfering with or damaging sensitive circuitry. They are required to preserve an isolation barrier in systems
using isolated devices requiring discrete power supplies.
The complementary output signals (SW1 and SW2) from the SN6507 are ground-referenced, N-channel, power
switches that drive the primary side of the center-tapped transformer. The secondary side of the transformer
has its center-tap referenced to an isolated ground plane, and the complementary outputs are rectified through
a two-diode bridge. The break-before-make feature of the two driver outputs from the SN6507 ensures that
only one of the primary-side transformer windings is driven at a time. After being rectified, the DC voltage
is smoothed and routed to an unregulated output to power external loads up to 500 mA, or the LM317A
voltage regulator can be enabled using jumper J4. Once enabled, the regulator outputs a stable, regulated
+12-VDC output by default that can also be used to drive up to 500 mA load circuits. As configured by default,
the SN6507DGQEVM complies with the CISPR 32 Class B radiated emissions standard, as shown by the
measurement in
.
Introduction
2
SN6507DGQEVM Low-Emissions 500 mA Push-Pull Transformer Driver for
Isolated Power Supplies Evaluation Module
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