A voltage-controlled duty-cycle oscillator (VCDCO) developed for use with integrated silicon sensors is described. The circuit's transfer function is, to first order, completely independent of component values. Measured results indicate that the circuit is capable of resolving input voltage changes as small as 6 mu V in a 2000- mu s period and has a dynamic range of 72 dB over the full commercial temperature range while operating from a 3-V supply. A two-terminal temperature transducer built using the circuit is presented.<>