The ADuM4138 is a single-channel gate driver optimized for driving insulated gate bipolar transistors (IGBTs). Analog Devices, Inc., iCoupler® technology provides isolation between the input signal and the output gate drive.
The Analog Devices chip scale transformers also provide isolated communication of control information between the high voltage and low voltage domains of the chip. Information on the status of the chip can be read back from the dedicated outputs.
The ADuM4138 includes an isolated flyback controller, allowing simple secondary voltage generation.
Overcurrent detection is integrated in the ADuM4138 to protect the IGBT in case of desaturation and/or overcurrent events. The overcurrent detection is coupled with a high speed, two-level turn off function in case of faults.
The ADuM4138 provides a Miller clamp control signal for a metal-oxide semiconductor field effect transistor (MOSFET) to provide IGBT turn off, with a single rail supply when the Miller clamp voltage threshold drops below 2 V (typical) above GND2. Operation with unipolar secondary supplies is possible with or without the Miller clamp operation.
A low gate voltage detection circuit can trigger a fault if the gate voltage does not rise above the internal threshold within the time allowed after turn on (12.8 µs typical). The low voltage detection circuit detects IGBT device failures that exhibit gate shorts or other causes of weak drive.
Two temperature sensor pins, TS1 and TS2, allow isolated monitoring of system temperatures at the IGBTs. The secondary undervoltage lockout (UVLO) is set to 11.2 V (typical) in accordance with common IGBT threshold levels.
A serial peripheral interface (SPI) bus on the primary side of the device provides in field programming of temperature sensing diode gains and offsets to the ADuM4138. Values are stored on an electrically erasable programmable read-only memory (EEPROM) located on the secondary side of the device. In addition, programming is available for specific VDD2 voltages, temperature sensing reporting frequencies, and overcurrent blanking times.
The ADuM4138 provides isolated fault reporting for overcurrent events, remote temperature overheating events, UVLO, thermal shutdown (TSD), and desaturation detection.
Applications
- MOSFET and IGBT gate drivers
- Photovoltaic (PV) inverters
- Motor drives
- Power supplies
