The LT3751 is a high-voltage DC/DC converter and capacitor charger that accepts input voltages from 4.75V to 400V. It features a 1.5A push-pull main driver and a 0.5A PMOS pull-up driver, providing excellent EMI performance and reliability
The document introduces the LT3751 as a general-purpose flyback controller capable of operating as either a voltage regulator or a capacitor charger. It features boundary-mode operation to reduce transformer size and audible noise, utilizing dual overlapping modulation techniques.
Key design features include high input voltage support from 4.75V to 400V, internal Zener clamps for safety, selectable gate driver clamp voltages (5.6V or 10.5V), and protection against over-temperature, no-load conditions, and short circuits.
The average output power must be less than 40W to keep the transformer temperature at or below 65°C.
The device takes inputs ranging from 4.75V up to 400V.
The output voltage trip point can be adjusted up to 450V by changing resistor R9.