Hello,
I got a question, has anyone had any experience with DGD05473 mosfet driver by Diodes Incorporated?
This is the datasheet:
The document looks very thin on details, I was wondering if anyone had done any work with it? The reason is they do not specify the sizing of the bootstrap capacitor, nor any other details, duty cycle, very little.
Thanks,
Valentine
Possibly this will help you out a bit
I just use 104 for bootstrap cap in all my application. Works just fine.
The bootstrap cap charged when low side mosfet is on, so maximum duty cycle should be limit under 100%. 97% is enough for several hundred khz.
The exact calculation has to do with many factors. e.g. freq, Ciss, VCC and so on. Thats a rabbit hole.
Rabbit holes are not a problem, as long as we catch the correct rabbit.
I kept digging into ONSemi’s and found this, perhaps they assume people know everything and decided to skip the actual write-up, my fear is that this is very generic, and I expected a driver-specific treatment inside the documents.
In fact this is by far one of the best treatment of driver designs I’ve read.
Only one way to find out. I paired NCP81155MNTXG up with CSD19534Q5A.
Also paired DGD05473 up with KNG3703A, and added current sense.
And at the end I remembered someone in another thread mentioned about UP9636PQMY:
Lots of free time in lockdown… nothing else to do.
Cheers.
The datasheet says the driver consumes <1uA when EN is at 0V, but the spice model (https://www.diodes.com/productcollection/spicemodels/8231/High-Side%2FLow-Side-Gate-Drivers.spice.txt) has a 40k resistor from VCC to COM, which means at least 112.5uA if the minimal 4.5V is present at VCC. Whom to believe?
Well, the driver and the external resistor are two separate components.
So both are correct. Add them up.
Cheers,
Valentine
