Today I saw an led dimmer product. the driving circuit was like in the schematic. it was a cheap one but the circuit looks inefficient to me. when the bjt not conducting, R1 pulls the gate high, and mosfet starts conducting that's ok. but when the bjt conducting(high signal on gpio) bjt shorts the gate to gnd. thats actualy commonly used circuit. but large amount of current (12V/150 = 80mA) flows through the gnd on R1. is it okay for a commercial product?
pwm frequency is seen as 500Hz on scope. obviously when they increase the R1, rise time of the mosfet get very high and switching losses dramaticly increase. they claim that this product can handle up to 20 amps(of course there is a heatsink on mosfet).
so the question is, is there any efficient solution to drive a gate without gate driver? is it the right way to drive a mosfet?