High-speed bipolar logarithmic analog-to-digital converter

摘要

A high-speed bipolar logarithmic analog-to-digital (A/D) converter outputs a signed binary number proportional to the logarithm of a bipolar analog input signal. A log converter is followed by a level shifting amplifier to center the output of the log converter on a temperature compensating reference. The reference voltage from the temperature compensating reference is used by a linear A/D converter to set the end points of the converter range. A code converter follows the A/D converter if a uniform absolute value coding is desired. Limiting the number of least significant bits (LSB) used to those representing the range of usable converter operation completes the device.