Good day everyone. I'm a night hawk so this is early for me but the dogs woke me to an intruder. (Lost sole, 1, & 1/2 mile off public road up a posted drive? Sure!)
Anyhow, I want to assemble a half bridge type drive and need a charge pump. It is only recently I have started messing around with MOSFET. (Recently being since I escaped the hospital several months ago.) I am not sure how much higher than the low side transistor the high side needs to be, or even the maximum for the charge pump.
Also frequency for the oscillator. I think I have this one too low, if the circuit I modeled it on is correct it should be adjustable up to 2, 2.5KHz. (Higher to refresh the boot better or more often maybe?)
Examples in applications notes use a much higher frequency and I can go higher if need I need to. The circuit will be operating at something like 36KHz, adjustable +/- 2KHZ maybe.
I have two extra comparators in the LM339 I will be using in the main circuit so that is the reason for the comparator as an oscillator. I think I have seen two used also but if one will work I'll stick with it.
Of course, I can build the circuit and smoke some transistors if need be, but with my shaky hands now days that is time consuming, if someone will lend their experience I would appreciate it.
Oh yes, I will be driving 2N7002 if they ever get here. SOT23 package and won't that be a challenge with my shaky hands?
Also another question; In the terms of service it is stated, GIF, JPEG or PGN should be used to up-load attachments. I have been using PDF but can convert quickly. Should I, or is PDF okay?
Thanks.
Roland
Anyhow, I want to assemble a half bridge type drive and need a charge pump. It is only recently I have started messing around with MOSFET. (Recently being since I escaped the hospital several months ago.) I am not sure how much higher than the low side transistor the high side needs to be, or even the maximum for the charge pump.
Also frequency for the oscillator. I think I have this one too low, if the circuit I modeled it on is correct it should be adjustable up to 2, 2.5KHz. (Higher to refresh the boot better or more often maybe?)
Examples in applications notes use a much higher frequency and I can go higher if need I need to. The circuit will be operating at something like 36KHz, adjustable +/- 2KHZ maybe.
I have two extra comparators in the LM339 I will be using in the main circuit so that is the reason for the comparator as an oscillator. I think I have seen two used also but if one will work I'll stick with it.
Of course, I can build the circuit and smoke some transistors if need be, but with my shaky hands now days that is time consuming, if someone will lend their experience I would appreciate it.
Oh yes, I will be driving 2N7002 if they ever get here. SOT23 package and won't that be a challenge with my shaky hands?
Also another question; In the terms of service it is stated, GIF, JPEG or PGN should be used to up-load attachments. I have been using PDF but can convert quickly. Should I, or is PDF okay?
Thanks.
Roland
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