Recommendation for boostrap circuit

Thread Starter

Erdem94

Joined Oct 14, 2021
9
Hi guys,
I am new in here. I designed a boostrap circuit with ir2112 ıc, but I want to rise up frenquency from 500k to 1mhz .
I wonder how do I make such a circuit ?
My circuit is bottom.
 

Thread Starter

Erdem94

Joined Oct 14, 2021
9
My car won't run. Why does it not run?

Since we are not clairvoyant, you need to tell us how does it not run.
What do the various node signals look like?
pardon firstly, I looked signals on ır2110, not output , but I drive ır2110 with flip flop circuit .I controled that Flip flop circuit is true .after I tried another with ır2110 ,but not triggering. I am curious at the circuit true??
 

Ian0

Joined Aug 7, 2020
3,754
An IR2110 will run even if the half-bridge is not powered up, so disconnect the 48V from the MOSFETs and see if you get a gate-drive waveform. This will prevent you from killing dozens of MOSFETs while you optimise it.

You are probably going to need some delays around U2 to prevent shoot-through. The IR2110 appears not to asd dead-times automatically.
Many half-bridge drivers automatically add a dead time, some as long as 2us. obviously, if you want to run at 1MHz, you need some deadtime to prevent shoot through, but no more than about 100ns. Probably you need a specialist half-bridge driver to run that fast, maybe one designed for class-D audio.
 

Thread Starter

Erdem94

Joined Oct 14, 2021
9
today , I look at the circuit.I think that Vhi and Vli need 12-15v logic pulse.
what if do you use that how many volt for logic pulse???
 

Ian0

Joined Aug 7, 2020
3,754
today , I look at the circuit.I think that Vhi and Vli need 12-15v logic pulse.
what if do you use that how many volt for logic pulse???
You are correct - minimum spec for VIH is 9.5V, on a 15V supply. It’s not the best datasheet - it also says that logic inputs are compatible with standard CMOS/TTL down to 3.3V, so I guess that the threshold is nominally half Vdd, so it should work with 5V logic provided that Vdd is also 5V. Vcc, however, should be higher than that, at least 10V.
 
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Thread Starter

Erdem94

Joined Oct 14, 2021
9
this is my result. Pulse source is flip flop circuit that is 125khz (high 15v, low 0v).Pulse source has little noise,so this result has some noise.Thanks you
 
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