CMOS Sigma-Delta Modulator with 90 dB Dynamic Range

This device is a 7th order sigma-delta modulator that converts the analog input signal into a high speed 1-bit data stream. The part operates from a +5 V supply and accepts a differential input range of 0 V to +2.5 V or ±1.25 V centered about a common-mode bias. The analog input is continuously sampled by the analog modulator, eliminating the need for external sample and hold circuitry. The input information is contained in the output stream as a density of ones. The original information can be reconstructed with an appropriate digital filter.

* 12.5 MHz Master Clock Frequency

* 0 V to +2.5 V or ±1.25 V Input Range

* Single Bit Output Stream

* 90 dB Dynamic Range