Quote:
Originally Posted by Ether
I like this one better, see Pages 18* & 19.
The Black Jags use the low side to provide the path for the inductive current during the OFF portion of the PWM cycle.
* there's a typo in the third paragraph in the section at the bottom of Page 18 titled "Switching Scheme". It should read "and Q4 on the low-side"
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Good catch, thanks. Hmm, I wonder why they didn't do this the other way or flip it over for the higher duty cycle.
Wouldn't it make it even more efficient?
Per this:
"During PWM_OFF, assuming a 40 A load, Q2 losses are approximately 40W without synchronous
rectification. This drops to just 4W if synchronous rectification is used (Rds-on = 2.5 mΩ).
Synchronous rectification significantly improves drive-stage efficiency, particularly at lower duty
cycles (50% and less) when the PWM_OFF time is longer that the PWM_ON time."
Besides I would think the Jaguars would tend to spend more time at a higher duty cycle in our application.