why linear drivers (inefficient and limited current) are so popular?

[EasyB]

@clientequator

I was looking at 7135 driver and I always wonder why everyone use it also. It make sense to use low number like 4 in circuit, but I see people with 20x of those chip on pcb and it seems a little confusing to me. why not use bigger transistor? a simple big but cheap mosfet will have better thermal and be cheaper.

also I read the 7135 datasheet and I notice you can also use this chip which can do 1A, call the 5710, about 3x the 7135 current capability at 1A, so why nobody use this one? Can easy make 3A led driver with just 3 of this 5710.

上海如韵电子有限公司-欢迎访问上海如韵电子有限公司主页!

I agree it would be nice to have an easier way to get more linear regulated current. Some discussion of this 5710 chip here.

Regulated 17mm 5A 1S driver options?

I’m using CN5710 (1A) and CN5711 (1.5A), using a digipot to adjust current. However, they are not compatible with 7135 design drivers (high side vs low side). There is more info in that giveaway thread: Driver giveaway: Constant current 17mm drivers, winners (finally) announced, post #2.

It regulates on the high side of the LED so it’s not a simple drop in for the 7135.