bandgap voltage reference?

wuwen

I would like to reply to our friend mt7344.
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They are multiple factors that you need to consider
(1) your requirement of Bandgap accuracy. Is it a 1% or a 10% bandgap? This actually depends on how you are going to use the Bandgap reference.
3 m9 `4 z0 B: N7 S/ F$ }(2) Process variations would be another factor, this is what out of our control. You can "Monte-Carlo" your circuit across the Vcc and process corners to determine your trimming ranges
  b: @% t9 y1 R6 |* A) ?(3) What you should control are the circuit components matching. Say the circuit posted by Mr Leonken01, matching of Q0, Q1; M0, M1, M2 and all the R are extremely important.
2 F* [. w- `3 J! X1 j0 t(4) Circuit structure also important, as the circuit mention above, it would be tough to match the current legs of M0, M1 and M2. Unless you need the low voltage Bandgap, I would not recommend this circuit
(5) On top of all these, your trimming range should also cover the TC, second order effect
: \: j" t* w4 E7 P" V: o- Wwill show up across temperature
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then you decide your trimming range and PAD needed.

7 O5 a1 E1 d4 T4 m* KHopefully these help.