UCC21225A: UCC21225A'S DT pin query..

Hi Anusha,

In this case, the driver will set the dead time according to the minimum specifications. This is outlined in the “DEADTIME AND OVERLAP PROGRAMMING” section of Table 6.9 in the datasheet, approximately 0–15ns.

Please note that TI’s recommendations are to either (1) tie the DT pin to VCCI or (2) place a 500-Ω to 500-kΩ resistor (RDT) between DT and GND, adjusting the dead time according to: DT (in ns) = 10 x RDT (in kΩ).

Best,

Olivia Brandel

Hi Anusha, 

That formula is given for a 500-Ω to 500-kΩ RDT. To control DT, we recommend this a resistor in this range. To allow overlap, we recommend connecting to VCCI. Outside of these recommendations, the best approximation we can give is that the DT will be between 0–15ns. A 0-Ω RDT will not necessarily yield 0ns DT.

Best,

Olivia Brandel