Abstract:

Conventional true logarithmic amplifiers exhibit high gain, but their gain varies significantly at high and low temperatures. A gain-stabilization design technique is presented, which reuses partial subcircuits of the original circuit and requires only a small number of additional components to achieve temperature compensation and gain stabilization. After adding temperature drift compensation, the gain variation of the circuit across high and low temperatures is reduced from 3.9 dB to 0.5 dB. It offers stable gain, wide dynamic range, high logarithmic accuracy, compact size, and ease of use, and can be widely used such as radar, sonar, communications, and electronic warfare systems.

Key words: true logarithmic amplifier, gain, temperature drift compensation, A/D conversion