Improved circuit to suppress the influence of power supply voltage waveform (b)

The above shortcomings can be overcome by changing VT3 in Figure 8-21(a) and (b) respectively
. In Figure 801, when the V-voltage decreases, the constant current value of VT3 also decreases, that is, IDI.Inz decreases,
so Jrcs also decreases, so VTl;: the voltage drop R on the collector resistor Rcs . ． Ia also decreases. This offsets
the change in output potential caused by the decrease in V1. Similarly, when V increases, Ra,. Jf. also increased. Therefore, the power supply voltage
fluctuation characteristics of the circuit shown in Figure 8-21 are better than those in Figure 8-20. The diode VD in Figure 8-21(a) is used to compensate for the temperature drift of VTi.