STNRG599ATR Resonant half bridge controller

The STNRG599 is a double-ended controller designed for series-resonant topologies, supporting both LLC and LCC configurations.

The IC provides two complementary outputs that drive the high-side and low-side MOSFET 180° out of phase. The dead time inserted between the turn-off of one switch and the turn-on of the other is automatically adjusted to fit the transition

times of the half-bridge midpoint, ensuring zero voltage switching across the entire operating range.

Output voltage (or current) regulation is obtained by directly controlling the phase shift between the half-bridge voltage and the resonant tank current. This proprietary control method, called phase shift control (PSC), enhances dynamic behavior and input voltage ripple rejection. Additionally, it makes the control loop with small sensitivity to component tolerance in the LLC / LCC resonant tank.

At light load, STNRG599 enters a controlled burst-mode operation, enabling intermittent converter operation. This reduces the average switching frequency and minimize the open-load input power.

STNRG599 is equipped with a full set of protection features: hard-switch prevention and anti-capacitive protection, 1st and 2nd level overcurrent protection, delayed shutdown and restart function based on pin DELAY (for user-programmable delayed shutdown upon overload with automatic restart). On the whole, OCP1, OCP2, and functions based on pin DELAY provide reliable and robust management of conditions such as short-time overcurrent, continuous overload, and severe output short-circuit.

DC brown-out/in protection is not latched. It is implemented at the input pin LINE, with constant hysteresis between brown-out and brown-in thresholds. The function prevents converter operation outside the selected DC input voltage range.