Talk:Widlar current source
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DC current mirror
editReference has been moved so link is no longer valid. —Preceding unsigned comment added by 75.82.213.125 (talk) 20:49, 11 April 2008 (UTC)
Source versus mirror
editAfter some careful analysis of the Widlar current source, I came to the conclusion that the this circuit is called source rather than mirror because the two currents on each branch of the circuit do not match. If I try to match the currents in both branches, I obtain an emitter resistance of 0Ω which is reducing the circuit to the simple current mirror. Does all this make sense or am I saying something stupid?
ICE77 (talk) 19:43, 24 May 2011 (UTC)
I get the same, even negative resistances for some configs.
Design procedure with specified currents
editI tried to get IO=5uA, IR1=10uA (best error%) in LTSpice and IR2=4.997uA while IO=4.869uA. Looks to me like 129nA of base current isn't accounted for in the right place. I would prefer that IO gets 4.997uA and IR2 = IO + IQ2B. But I ain't smart enough to fix the formula.