ADP3624 question

Question

this question might seem dump but I'm not completely sure if I can use this device for a Half-Bridge http://www.analog.com/en/products/monitor-control-protection/high-side-switches-mosfet-drivers/adp3624.html#product-overview

there is this picture

and the most ICs for Half-Bridges i've seen have something like a ?bootstrap? where the source of the highside Mosfet is connectet to the drain of the low side and fed into the IC.

My question is "can I use this to drive a Half-Bridge?"

edit:

I need to drive a BLDC so I need 3x Half-Bridges. During the commutation I never turn on a high Mosfet and right after that commutation its low Mosfet on, which means I can almost never shoot-trough one side? I'm using 20kHz PWM. I tried using a MIC4607

But I encountered great difficulties with the outputs sometimes not working properly or just not switching (changed 2x the ic). So i want to use something with no bootstrap or other means, just a crude way to get more current into my Mosfet gates

Answer 1

This seems to be a low-side driver only.

For your application you need to search on your favorite shop (digikey, mouser, etc) in the "MOSFET driver" category, and select the subcategories "half-bridge" or "high and low side" or "dual, synchronous". Or full-bridge if you want a full bridge, of course, but you can use two half-bridge drivers for this.

Here's an example, from AD and OnSemi.

This answer contains an excellent explanation on how a bootstrap driver works, so I don't need to say more ;)

Gotchas:

• Some drivers include anti-shoot-through (ie, they won't turn both FETs ON at the same time) and/or adaptive/adjustable dead time. If the driver doesn't have anti-shoot-through, taking care not to turn both FETs ON at the same time is your problem. Watch out for software bugs in your controller...

• Some drivers include a charge pump and can keep the high-side FET ON continuously, others use a bootstrap cap which needs to be recharged, so they can never be ON continuously, the PWM will have to pulse low periodically. Not a problem at all, just gotta be aware of it.

• Some can start with the bootstrap cap discharged, others can't. This is important if you want to make a buck battery charger. If there is a high enough voltage on the output of your buck due to a battery being there, the bootstrap cap can't charge without pulsing the output low, and that doesn't work if the driver requires the cap to be charged in order to function... This problem does not occur if your load is a motor or anything else that has 0V across it on startup.