An inherently linear and compact MOST-only current division technique

A technique is presented for dividing currents accurately and linearly by using MOS transistors only. This technique is valid in all operating regions of an MOS transistor. With this technique, a volume control circuit is realized with an attenuation of 0 to -84 dB in steps of 2 dB. The measured THD is better than -85 dB and the dynamic range is better than 100 dB. The chip is realized in a standard digital CMOS process and chip area is 0.22 mm/sup 2/.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>