Copyright © 2017, Texas Instruments Incorporated
General Overview
4
SLLU282A – December 2017 – Revised February 2018
Copyright © 2017–2018, Texas Instruments Incorporated
UCC5390SCD With Isolated Bias Supply
shows the board image of the EVM.
Figure 2. UCC5390SCDEVM-010 Board Image
The EVM includes an isolated driver, UCC5390SCD, and bias supply, SN6505B. The UCC5390SCD
device is part of the UCC53xx family of drivers, in an 8-pin SOIC package including variants with different
pinout configurations and drive strengths. For this design, the UCC5390SCD device, with split output, 17-
A, and typical current capability, has been selected for its ability to optimally drive FETs and IGBTs in mid-
and high-power applications. The SN6505B device is a push-pull transformer driver, operating at 420 kHz
to provide a compact bias solution for isolated drivers, digital isolators, sense circuits, and various
communication buses. See the
UCC53x0 3-kVRMS Single-Channel Isolated Gate Drivers
data sheet and
SN6505 Low-Noise 1-A Transformer Drivers for Isolated Power Supplies
data sheet for more information
about the UCC5390 isolated driver and SN6505B transformer driver.
The primary side of the EVM is supplied by a 3-V to 5.5-V external voltage source. This voltage is
converted and isolated through a high-frequency transformer to provide bias voltage from 11-V up to 33-V
range to the secondary isolated side of the driver. Bias supply is an unregulated DC-DC transformer, so
the variation of primary voltage directly impacts the secondary side voltage. Therefore, TI recommends an
external voltage source regulated within 5% to 10% for this design. The driver has two inputs: inverted and
non-inverted. One input can be used for the PWM signal and the other as Enable. The driver has split
outputs that, through gate resistors, are connected to output holes to allow direct soldering to the power
device in TO-220 or TO-247 packages. The secondary side of the bias supply includes a rectifier circuit
that can be configured as center-tapped or bridge, therefore expanding the range of available bias
voltage. The secondary side also includes a circuit to generate a split rail with negative turn OFF bias for
applications and power devices where dv/dt-induced, spurious turn ON may be a potential issue.
2.1
Features
•
Compact, isolated gate driver board for direct connection to power FETs and IGBTs in high-voltage,
mid-, and high-power converters and inverters
•
Split output, 17-A, typical sink and source drive current for optimal turn ON and turn OFF settings
•
Single or split rail bias supply configuration in 11-V to 33-V range
•
Robust, noise-immune solution with CMTI > 100 V per ns
•
Supports 3-kVrms basic isolation
•
Provides up to 0.8-W drive power using 80% efficient bias supply
