UCC27221

UCC27222

SLUS486B − AUGUST 2001 − REVISED JULY 2003

6

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APPLICATION INFORMATION

predictive gate drive technique

The Predictive Gate Drive

t technology utilizes a digital feedback system to detect body-diode conduction, and

then adjusts the deadtime delays to minimize it. This system virtually eliminates the body-diode conduction time

intervals for the synchronous MOSFET, while adjusting for different MOSFETs characteristics, propagation and

load dependent delays. Maximum power stage efficiency is the end result.

Two internal feedback loops in the predictive delay controller continuously adjusts the turn on delays for the two

The predictive delay controller is implemented using a digital control technique, and the time delays are

switching cycle. The minimum and maximum turn-on delays for G1 and G2 are specified in the electrical

characteristics table.

tOFF,G1

tOFF,G2

tON,G1

tON,G2

G1

G2

3.25 V

10%

90%

90%

10%

3.25 V

UCC37222

UCC27221

IN

Figure 2. Predictive Gate Drive Timing Diagram

UCC27221

Not Recommended For New Designs