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 Figure 2-1.

Use this EVM to evaluate electrical and timing parameters of the SN6507 device in different configurations. Apply power to evaluate performance characteristics such as enable delay, rise and fall times, soft-start duration, and power consumption for different load conditions. This EVM offers provisions for a wide range of configurations, as detailed in Section 4.