Hello,
I'm having a little trouble understanding how to power an International Rectifier IR2155 half-bridge self-oscillating MOSFET driver. The datasheet shows a basic usage model where the device is powered by the high-voltage to be switched:
However, the supply pin has a 15.6V Zener across it, which causes the supply voltage to drop to 15.6V. So my Vhi clamps to 15.6V, instead of 80~100V. Obviously defeating the point.
The footnotes on the device max table mentions that it must be powered by a current source, and I've only seen one example of that using an LM334Z, which I don't understand.
Any ideas how to supply this thing? FYI: the input voltage I'm trying to switch is 80~100V DC from a boost converter. I thought about just using a 555 with a simple mosfet driver, but would like to understand this odd device's power requirements, just for the sake of curiosity.
Thanks,
Peter