The NE1185 is a controller designed specifically for the resonant half-bridge topology. It provides two drive-signal channels that output complementary signals at a 50% duty cycle. An internal fixed dead-time of 320ns between the two complementary gate signals guarantees zero-voltage switching during the transient and enables high-frequency operation.

The integrated bootstrap diode simplifies the external driving circuit for the high-side switch. It can withstand up to 600V with immunity against high dV/dt noise.

Modulating the switching frequency regulates the topology output voltage. A programmable oscillator can set both the maximum and minimum switching frequencies.

The IC starts up at the programmed maximum switching frequency and gradually slows until the control loop takes over to prevent excessive inrush current.

The IC can be forced to enter a controlled burst-mode operation at light-load to minimize the power consumption and tighten output regulation.

IC‘s functions include a not-latched active-low disable input with current hysteresis useful for power sequencing or for brownout protection, a current sense input for OCP with frequency shift and delayed shutdown with automatic restart. A higher level OCP latches off the IC if the first-level protection is not sufficient to control the primary current. Their combination offers complete protection against overload and short circuits.

The IC provide 0.9A/1.5A source/sink capability for both high-side and low-side gate drivers.

The NE1185 is available in a SOP-16 package.