yes i want 9A not 10A.....You are saying that your load is 1 Ω and that it is powered from 9 V. How do you expect to get 10 A into it in the first place?
Look at the data sheet for the TIP-142 and you will see that the Vce saturation voltage at 10 A (and Ib = 40 mA) is spec'ed to be less that 3 V. So even if you only got 6 A you would have nothing to complain about.
yes i think i know both Darlington transistorDid you know that both the TIP122 and the TIP142 are Darlington transistors? You do know what that means -- Right?
You start with 9 V. You have a transistor that saturates with as much as 3 V from collector to emitter. That leaves 6 V across your load, which is 1 Ω. How much current will flow through a 1 Ω load that has 6 V across it?yes i want 9A not 10A.....
why i can't get 9A from tip141? now i get 6A no more...what is the wrong?
So why are you using two Darlingtons in a Darlington configuration? The TIP-142 has a beta of ~500, meaning that to support 10 A you would only need 20 mA of base current. What can the PIC provide?yes i think i know both Darlington transistor