Low pulse width distortion high speed photocouplers

Louise Smyth

Toshiba Electronics Europe has launched two new high speed photocouplers, TLP2745 and TLP2748. The new IC output photocouplers feature low Pulse Width Distortion (PWD) and low power consumption for high speed, high temperature operation. The new photocouplers have been designed for applications such as high-speed digital interfaces for measurement or control devices, intelligent power module (IPM) drives and programmable logic controllers for use in industrial settings.

The TLP2745 is a buffer logic type (high input → high output) photocoupler, while the TLP2748 is an inverter logic type (high input → low output) coupler, both provide an isolation voltage of min. 5000Vrms.

Demand in recent years for energy-saving products has brought about a need for increasingly efficient power systems. Featuring a high speed propagation delay time of 120ns (max) for higher operational efficiency while guaranteeing 40ns (max) pulse width distortion and 70ns (max) propagation delay skew, these new ICs allow the reduction of inverter dead time, contributing to an overall improvement in power efficiency. In addition, by guaranteeing a threshold input current of 1.6mA (max), they allow bufferless direct drive from microcomputers, and as such a reduction in energy consumption and cost.

With an operating temperature range of -40°C to 110°C, and a wide supply voltage range (VCC=4.5 to 30V), these ICs are suited to communication interfaces (such as RS232, RS422, and RS485) including use in industrial applications, and data transmission solutions between circuits with different voltages. The TLP2745 and TLP2748 are housed in an SO6L package, measuring 10mm x 3.8mm x 2.1mm and they guarantee a creepage distance of min. 8mm.