Controllable voltage to current converter e.g. for controllable filter - has input stage formed by differential amplifier with fixed steepness or presettable control

摘要

The converter has an input stage (1) for receiving an input voltage (UIN), and an output stage (2), delivering the output current (IA). The input stage is formed as a differential amplifier stage with a fixed steepness or preset energising. A control current part (3) processes an external input current (IE). From each input current is formed at least one control current (ISt). The control current is used for variation of the output current of the output stage coupled to the control current part. Pref. the output stage has at least one current mirror, to which the control currents from the control current part are supplied. Thus the output stage output is energised, while the current mirror ratio can be varied by the control currents to affect the output current. USE/ADVANTAGE - For amplifier or filter circuit with wide control range.