Toshiba introduces an optocoupler with built-in protection for high-current IGBT/MOSFET

     Toshiba Electronic Components & Storage Corporation announced the launch of the "TLP5231," a pre-drive optocoupler for medium and large current insulated gate bipolar transistors (IGBTs) and MOSFETs for power regulation systems in industrial inverters and photovoltaics (PV). The new pre-driven optocoupler has a variety of built-in features, including overcurrent detection by monitoring the collector voltage.

     The new predrive optocoupler uses external P-channel and N-channel complementary MOSFETs as buffers to control high-current IGBTs and MOSFETs. Existing products need to use a buffer circuit composed of bipolar transistors to achieve current amplification, which consumes base current in operation. The new product is able to use an external complementary MOSFET buffer that consumes current only when the gate of the buffer MOSFET is charged or discharged, helping to reduce power consumption.

     By varying the size of the external complementary MOSFET buffer, the TLP5231 is able to provide the required gate current for a variety of IGBTs and MOSFETs. The TLP5231, MOSFET buffer, and IGBT/MOSFET configurations can be used as platforms to meet the system's power requirements, simplifying the design.

     Additional features include: Control of "gate soft shutdown time" using another external n-channel MOSFET after detection of VCE(sat) overcurrent; In addition to VCE(sat) detection by monitoring the collector voltage, there is also UVLO[3] detection, which outputs any fault signal to the primary side. These new features, which are not available in existing products [2], allow the TLP5231 to make it easier for users to design gate drive circuits.