Monday, August 17, 2009

Gate Drive Transformers and Isolation Transformers

Power MOSFETs often require a gate drive circuit to translate the on/off signals from an analog or digital controller into the power signals necessary to control the MOSFET. If the transformer is designed with low leakage inductance the propagation delays through the transformer can be less than 50 ns. The transformers from ICE Components offer a leakage inductance of a few hundred nanoHenries. This low value is obtained by using tightly coupled windings on a small ferrite core. Gate drive transformers from ICE Components have been tested and compared and shown to have some of the lowest leakage values seen in the industry.

The GT series is also often used as an isolation transformer. Sometimes a timing signal must be provided between primary to secondary. All transformers provide dc isolation between isolated windings. However, because they all have capacitance from a winding to any nearby conductor, such as other windings, the core, and the chassis, they can couple high frequency signals and noise to these nearby conductors. This capacitive coupling mechanism can carry high frequency noise on the input primary to the output secondary windings or vice versa. Isolation transformers from ICE Components offer very low interwinding capacitance values to minimize high frequency noise coupling. Isolation transformers from ICE Components have been tested and compared and shown to have some of the interwinding capacitance values seen in the industry.

GT01 Series
The GT01 series offers the smallest size available on the market and is designed for frequencies from 500 kHz to over 1 MHz and multiple turns ratios are available. With E-T Product values over 10 volt-microseconds, the GT01 series can be an effective gate drive transformer or isolation transformer.

GT02 Series
The GT02 series offers a low profile option with a maximum height of 3 mm and a higher Hi-Pot isolation (1500 Vdc) than the GT01 series. Also effective as an isolation or gate drive transformer.

GT03 Series
The GT03 series is our most popular series with ET Product values up to 69 volt-microseconds and Hi-Pot values up to 3750 Vac. This series also comes in a potted version offering creepage / clearance over 10 mm to meet medical VDE. The small package (10.7 x 16 x 6.8) and power performance meet many gate drive and isolation transformer requirements.

GT04 Series
The GT04 series is used for higher power applications and offers ET Product values to 378 volt-microseconds and Hi-Pot values up to 4500 Vdc. The GT04 series also meets medical safety isolation requirements.

The ICE Components family of gate drive transformers offer a wide range of standard product, but we also make many custom products based on customer applications and specific needs. We can easily adjust turns ratios and insulations systems for different temperature ratings, isolation voltages, as well as creepage / clearance needs.