What is the best way to drive a MOSFET with low voltage?
I have encountered several projects where power from a battery is used to drive motors or source a DC/DC converter.
In most cases, we used an IC fitting our needs, but I always wondered how to drive a MOSFET half-bridge at low voltages.
I'm used to bootstrap drivers working with 10V+.
Is it worth it to boost voltage high enough to drive the gate driver with a small PMIC, or are discrete solutions better for low voltage applications?
As an example, what solutions would you recommend for a synchronous boost converter with the specs:
- Uin = 1.8V
- Uout = 4.2V
- Iin(max) = 2A
- f = 250kHz
I'm more comfortable with two N-ET and a driver, but are there other solutions?
I'm not interested in integrated controllers for DC/DV converters.
I'm looking for an answer to the question: "How do you fast switch a MOSFET with low voltage?"