LTC7893/LTC7892: 100V Low IQ, Synchronous Boost Controllers for GaN FETs

The LTC7893/LTC7892 are high-performance, step-up DC-to-DC switching regulator controllers that drive all N-channel synchronous gallium nitride (GaN) field-effect transistor (FET) power stages from output voltages of up to 100V.
 
The LTC7893/LTC7892 solves many of the challenges traditionally faced when using GaN FETs. It simplifies the application design while requiring no protection diodes and no other additional external components compared to a silicon metal-oxide-semiconductor field effect transistor (MOSFET) solution.
 
The Internal smart bootstrap switches prevent overcharging of the BOOSTx pin to the SWx pin the high-side driver supplies during dead times, protecting the gate of the top GaN FET. The dead times of the LTC7893/LTC7892 can optionally be optimized with external resistors for margin or to tailor the application for higher efficiency and allowing for high-frequency operation.
 
The gate drive voltage of the LTC7893/LTC7892 can be precisely adjusted from 4V to 5.5V to optimize performance and allow the use of different GaN FETs or even logic-level MOSFETs. When biased from the boost converter regulator output, the LTC7893/LTC7892 can operate from an input supply as low as 1V after start-up.