9.3.1.6 OUT

OUT is the output of a high-current power driver capable of driving the gate of a power MOSFET with peak currents exceeding 750 mA. OUT is actively held low when VCC is below the UVLO threshold. The high-current power driver consists of FET output devices, which can switch all of the way to GND and all of the way to VCC. The output stage also provides a low impedance to overshoot and undershoot. This means that in many cases, external Schottky clamp diodes are not required.

The output of the UCC280x-Q1 is a CMOS output versus a Bipolar output on the UC3842 family. Peak output current remains the same ±1 A. The CMOS output provides very smooth rising and falling waveforms, with virtually no overshoot or undershoot. Additionally, the CMOS output provides a low resistance to the supply in response to overshoot, and a low resistance to ground in response to undershoot. Because of this, Schottky diodes may not be necessary on the output. Furthermore, the UCC2802-Q1 has a self-biasing, active low output during UVLO. This feature eliminates the gate to source bleeder resistor associated with the MOSFET gate drive. Finally, no MOSFET gate voltage clamp is necessary with the UCC280x-Q1 as the on-chip Zener diode automatically clamps the output to VCC.