http://cds.linear.com/docs/en/datasheet/134sfc.pdf Source

What I know (I think): Q1 and Q2 are PNP transistors. A1 is a differential amplifier. When A1's output is low, current through Q1 and Q2 is increased. The Q1 and Q2 collector voltage must be less than the A1 output voltage.

How do I calculate the collector voltage of transistors Q1 and Q2 in this constant current circuit?

  • \$\begingroup\$ National Semi, the original design/manufacturer of the lm134 has a better datasheet (now ti) ti.com/lit/ds/symlink/lm334.pdf \$\endgroup\$ – sstobbe Jul 11 '17 at 1:50
  • \$\begingroup\$ When in linear regulation \$V_{C,1}\$ = V- and \$V_{C,2}\$ = V- + 64 mV (at roomtemp, voltage ref is deltaVbe derived and hence PTAT) \$\endgroup\$ – sstobbe Jul 11 '17 at 1:53

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