Patent ID: 7417486
Filing Date: 2008-08-26
Classification: H03D,H03F

Abstract:
1. A voltage-current conversion circuit comprising a transconductance stage for carrying out voltage-current conversion, the transconductance stage comprising: a first transistor and a second transistor each comprising a collector connected to a respective power source terminal, and each receiving an input signal from a respective base; a third transistor comprising a collector connected to an emitter terminal of the first transistor and a fourth transistor comprising a collector connected to an emitter terminal of the second transistor, the collector of the third transistor being cross-coupled to a base of the fourth transistor, and the collector of the fourth transistor being cross-connected to a base of the third transistor; a fifth transistor for acquiring a current signal from a collector of the fifth transistor, the fifth transistor and the third transistor sharing the base and an emitter: and a sixth transistor for acquiring a current signal from a collector of the sixth transistor, the sixth transistor and the fourth transistor sharing the base and an emitter, wherein: the first to fourth transistors each have an m-row of parallel connections of transistor elements; the fifth and sixth transistors each have an n-row of parallel connections of transistor elements; a resistor element is provided between the emitters of the fifth transistor and the sixth transistor; and a transconductance (gm) is determined by m, n, and resistances of the resistor element.