[Introduction]Regarding the IGBT/MOSFET pre-driver, I believe that engineers who are motor drivers or high-power equipment drivers will know something. The so-called pre-driver actually isolates the microcontroller from the IGBT/MOSFET to provide protection for the load and driver. , and provides diagnostic information to the microcontroller (MCU). This kind of pre-driver is usually built with op amp, MOS or triode, etc. On the premise of protecting the driver and microcontroller, it also realizes the comparison of the drain-source voltage (VDS) of the MOSFET with the reference voltage, Realize status diagnosis; then do you know that optocouplers can actually be used as pre-drivers for IGBT/MOSFET? Toshiba has been cultivating IGBT/MOSFET products and optocoupler application technology for many years. This pre-driver for medium and high current IGBT/MOSFET, TLP5231, is the supplement and improvement of Toshiba’s semiconductor series product line.
1. Analysis of electrical characteristics
TLP5231 consists of two infrared light-emitting diodes (LEDs) and two high-gain high-speed light-receiving IC chips, so as to realize the feedback function of fault signals. It is packaged in SO16L, and the output peak current is up to ±2.5A.
The TLP5231’s ability to use an external complementary MOSFET buffer and consume current only when the gate of the buffer MOSFET is charging or discharging helps reduce power dissipation.
TLP5231 can provide effective common-mode transient suppression of ±25kV/µs, thereby improving EMI in the circuit, and has an isolation voltage of 5kv, a wide range of operating temperature from -40℃ to 110℃, excellent anti-interference ability, and can cope with different tasks Scenes;
The specific parameters are as follows:
(Unless otherwise stated, Ta = -40°C to 110°C)
2. Analysis of functional characteristics
1. Simplify dead time design
The TLP5231 contains dual outputs with active timing control, which eliminates the need for dead-time design and prevents switching losses due to simultaneous conduction. Suitable for driving P-channel and N-channel complementary MOSFET buffers.
2. Improve the flexibility of soft-shutdown design
When overcurrent is detected, since this soft-off MOSFET does not use the same wire (line) as the MOSFET Q2 snubber, a configurable gate soft-off time is achieved by using another external N-channel MOSFET, thus increasing design flexibility properties and does not affect normal shutdown operation.
3. Automatic reset of fault signal
When monitoring the collector voltage to detect overcurrent or undervoltage lockout, a fault signal is output to the primary side. Therefore, compared with the traditional IGBT/MOSFET, it supports the design as a pre-driver.
3. Application scenarios
TLP5231 optocoupler is mainly aimed at the isolation gate drive circuit of medium and high current IGBT and MOSFET. The main application scenarios can be industrial equipment (industrial inverter and photovoltaic inverter power conditioner, etc.) or uninterruptible power supply (UPS).
Toshiba has sharpened its sword on IGBT and MOSFET pre-drivers for ten years, and has done enough homework in the miniaturization and circuit simplification of pre-drivers. Through its continuous accumulation of experience and summarization of customer needs, it is believed that pre-drivers will be used in the future. In terms of products, Toshiba’s pre-driver product selection and reference will be very valuable.