I don't know what the B means.....I just know that all the other variants of this chip don't do constant off time. I used the Clare part once and spent an hour wondering why the board didn't work, then looked at the bom and saw it wasn't hv9910b....changed it and it worked.
Give us a shout if you need the inductor smaller....the calcs for that are a few minutes at most.
Interesting to see you used a 220uH inductor (instead of my 100uh recommendation) , and that you also adjusted the RT resistor to suit this.....this suggests that you have more knowledge about this than I first thought?
INDUCTOR:
To get the inductor smaller, use a Epcos PQ3535 core (N92 material) and put in a 0.6mm gap, and have 19 turns of 1mm wire. That will give you 100uH , start of saturation is 8.35amps.
epcos pq3535 core:
https://www.epcos.com/inf/80/ds/b65881a.pdf
Give us a shout if you need the inductor smaller....the calcs for that are a few minutes at most.
Interesting to see you used a 220uH inductor (instead of my 100uh recommendation) , and that you also adjusted the RT resistor to suit this.....this suggests that you have more knowledge about this than I first thought?
INDUCTOR:
To get the inductor smaller, use a Epcos PQ3535 core (N92 material) and put in a 0.6mm gap, and have 19 turns of 1mm wire. That will give you 100uH , start of saturation is 8.35amps.
epcos pq3535 core:
https://www.epcos.com/inf/80/ds/b65881a.pdf
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