I'm using a MOSFET for a sample and hold circuit controlled by a microcontroller. I want to control the charging and discharging of a capacitor by a solar cell. For this I'd be using two MOSFETs. The solar cell can have a large area and can source upto 3.2 A of current. This flows through the drain of the MOSFET. I want this flow to be switched ON and OFF by applying a gate voltage from an MCU. I can boost the MCU output to required gate voltage levels, but what would be a suitable MOSFEET for my application? I'd need approximately 250 ms ON time and 750 ms off time during switching. The IC (or transistor) package may be any one of the packages that may be connected to a breadboard easily that is NOT surface mount.
EDIT: Strictly speaking, the purpose isn't sample and hold but its very similar. I'd like to characterize the solar cell IV by sampling the voltage across the cap and the current flowing to it while charging.
Best Answer
While a schematic of the application, and the solar panel voltage, would make it simpler to provide a definitive answer, here is how one could select a suitable MOSFET:
So, given the above parameters, a search on Digikey yields at least 79 results as I just checked. On sorting by lowest price for single unit purchases, a couple of options are:
Of course, if SMD were an option, many, and less expensive, options would open up, including some excellent devices by Alpha Omega and International Rectifier.
As pointed out by Russell, if providing a gate drive voltage higher than the MCU power rail is not a problem, and a P-channel MOSFET is preferred, then a similar Digikey MOSFET search yields several P-channel MOSFETs that meet the specifications above, setting aside the VGS(th) point. For instance: