摘要 |
An amplifier for systems affected by changes in operating temperature, in which the amplifier gain is stabilized over temperature. A temperature compensating control element is added to the previously known active bias control amplifiers, forming a second control loop. This control acts to modify the device bias current, in a way which holds the device gain constant as temperature varies. In so doing it implements, in the circuit, the mathematically derived current variation which, based on the physics of the device, maintains constant gain. The additional circuitry is very inexpensive, preserving the cost-effectiveness of the integrated circuit bias scheme for those applications requiring the additional bias control.
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