I'm needing to switch up to a few 100mA to a device, must switch the source rather than the sink, and only have n-channel mosfets to hand, specifically 30A STP36NF06's. The supply is 12V and with logic level gate voltage. Taking into account the voltage drop through the FET in resistor calculations for the current, this appeasr to work and I'm wondering what the downside is to using the device to source current rather than sink it? For example, does the MOSFET need to be derated, is it likely to fail after a time because it simply shouldn't be used this way, or is it inefficient but in princple ok? Guidance appreciated.
- posted
17 years ago