Chip drives 200V GaN half-bridge at up to 50MHz

Called LMG1210, it is designed to work with enhancement mode GaN and has a 10ns propagation delay.

“The device provides a low switch-node capacitance of 1 pF, with user-adjustable dead-time control which helps improve efficiency,” according to Mouser, which is stocking the part. “The LMG1210 offers 3.4ns high-side-to-low-side delay matching, a minimum pulse width of 4ns, and an internal LDO that ensures a gate-drive voltage of 5 V regardless of supply voltage.”

The bootstrap diode that charges the high-side bootstrap capacitor (see diagram) is not integrated to allows the designer to choose an optimal device – and an internal switch turns the bootstrap diode off when the low side is off “effectively preventing the high-side bootstrap from overcharging and minimising the reverse recovery charge”, said TI.

Output currents are 1.5A peak source and 3-A peak sink.

For noise immunity, recommended maximum high-side slew-rate is 300V/ns.

There are two control modes:

• Independent input mode routes two inputs separately to the two outputs, putting shoot-through protection into the hands of the external pulse generator.
• In PWM mode, the two complementary output signals are generated from a single input, with th euser setting resistors to adjust dead-time from 0 to 20ns for each edge.

Operation is over -40°C to 125°C, and the package is a low-inductance WQFN.

Applications are expected in high-speed dc-dc converters, motor control, Class-D audio amplifiers, Class-E wireless charging and RF envelope tracking.