A high-voltage temperature compensated logarithmic amplifier suitable for integration in a BiCMOS power controller IC

A new logarithmic amplifier suitable for integration in controller IC's for power electronics systems is introduced. The amplifier can be implemented in standard BiCMOS technologies commonly used to manufacture controller IC's but consumes little silicon real estate as compared to commercial log amplifiers, leaving room for primary controller features. Particularly suitable to high voltage measurements at low power, the amplifier includes internal temperature compensation. The amplifier is in fabrication using the TSMC 0.35 /spl mu/m technology node. Simulations results at a single supply of 3.3 V predict true logarithmic performance with only 1.5 mW of quiescent power consumption. The active area of the amplifier (sans I/O pads) is 100 /spl mu/n x 125 /spl mu/n.