Integrated triangular to sine wave converter circuit - has connection to external precision resistor and single ended output using matched bipolar pair and two constant current drives

摘要

The triangular to sinusoidal wave signal converter circuit consists of a bipolar transistor connected to supply voltage by its collector and to a reference voltage by its emitter through a constant current source. The triangular waveform signal is applied to its base. The emitter of the transistor is also connected to the supply voltage by a diode and a constant current source set to deliver half of the current of the first. The sinusoidal output is connected to the junction between this constant current and the diode and to a reference voltage by a resistor of chosen value. The diode is formed from a matched transistor with its collector and base terminals linked, the two transistors being joined by their emitters. The collectors of the transistors are connected to supply through a pair of balancing transistors. The circuit produces very low harmonic distortion and is better suited to integration than earlier variants.