I'm working on an ultrasonic transducer driver circuit, originally designed by Lindsay Wilson, and I'm currently seeing spikes at the switching junction. I'm running out of things to troubleshoot, so I'm taking a very good look at my N-Channel MOSFET orientation.
I am using STP13NK60Z N-Channel MOSFETs.
According to the documentation listed above, for the TO-220 package the pin layout is as follows:
The relevant part of the driver circuit shows the MOSFETs like this:
Looking at "Figure 1." The internal diode "points" from Source (Pin 3) to Drain (Pin 2). (So far so good.)
Looking at the Circuit Schematic for the driver the top MOSFET, Q1, appears to show the internal diode pointing from Drain (Pin 2) to Source (Pin 3).
Now, my questions are:
- Am I interpreting this correctly?
- Does it matter if pins two and three are reversed in practice?
Thanks for any help.