The LTC7890 is a high performance, dual step-down, dc-to-dc switching regulator controller that drives all N-channel synchronous gallium nitride (GaN) field effect transistor (FET) power stages from input voltages up to 100 V. The LTC7890 solves many of the challenges traditionally faced when using GaN FETs. The LTC7890 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 high-side driver supplies during dead times, protecting the gate of the top GaN FET. The LTC7890 internally optimizes the gate driver timing on both switching edges to achieve smart near zero dead times, significantly improving efficiency and allowing for high frequency operation, even at high input voltages. Alternatively, the user can adjust the dead times with external resistors for margin or to tailor the application.

The gate drive voltage of the LTC7890 can be precisely adjusted from 4 V to 5.5 V to optimize performance and to allow the use of different GaN FETs or even logic level MOSFETs.

APPLICATIONS

• Industrial power systems
• Military avionics and medical systems
• Telecommunications power systems