Mini high performance voltage regulator - with only 1 V drop

7-40 — elektor july/august 1982 One thing is common to virtually any voltage regulator; the input voltage level must be several volts higher than the expected output. Admittedly those fewer volts at the output are very nicely regulated. However, if for some reason there are very few volts at the input to start with, then there is a limitation in the output voltage range (far less volts to throw away!). In this case it is not possible to use a normal IC voltage regulator and we have to resort to a discrete design. The circuit shown here will operate with a 6 V input and provide a regulated 5 V output, which is ideal for battery powered equipment. With a little study the "trick" in the circuit will be apparent. The load is connected to the collector of the series transistor. This means that this transistor can be switched hard on into saturation, so that the voltage between emitter and collector is only the very small saturation voltage. This voltage level depends of course on cur...