The circuit of Fig. P5.35 is called the Widlar bandgap reference for its inventor. (a) Assuming matched BJTs with negligible base currents, show that VBG 5 VBE3 1 KVT, K 5 (R2yR3)ln (IC1yIC2). (b) If...

The circuit of Fig. P5.35 is called the Widlar bandgap reference for its inventor. (a) Assuming matched BJTs with negligible base currents, show that VBG 5 VBE3 1 KVT, K 5 (R2yR3)ln (IC1yIC2). (b) If Is (25 8C) 5 2 fA for all BJTs, specify R1 through R3 for TC(VBG) 5 0 at T 5 25 8C under the constraint IC1 5 IC3 5 5IC2 5 0.2 mA. (c) Specify R4 through R6 for VREF 5 5.0 V.