Low Voltage Darlington Amplifier

Abstract

The invention discloses a low-voltage Darlington amplifier. It includes a basic Darlington amplifying unit, an AC-DC separation unit and a power supply voltage polarity conversion unit. The circuit of the present invention separates the AC and DC grounds of the Darlington amplifier unit, and clamps the AC ground to the ground; the circuit of the present invention clamps the DC reference ground of the Darlington amplifier to a negative reference level, thereby improving the power supply Potential difference between voltage and DC reference ground. The power supply voltage of the traditional Darlington amplifier is generally higher than 5-7V, and the power supply voltage of the low-voltage Darlington amplifier of the present invention can be as low as 3-4V. The invention is widely used in various Darlington structure circuits in microwave monolithic ICs.

Description

technical field [0001] The invention relates to a Darlington amplifier, in particular to a low-voltage Darlington amplifier, which is directly applied to the field of various Darlington circuits in microwave monolithic ICs. Background technique [0002] The amplifier is a key unit in the RF signal processing system, and its performance directly determines the performance of the RF signal processing system. Darlington amplifiers have been widely used because of their wide operating frequency band, high linearity, and easy cascading. [0003] When the Darlington amplifier is working, it needs an external bias current, which is generally realized by a voltage source and an external bias resistor. The larger the voltage drop across the bias resistor, the more stable the Darlington amplifier's bias current is over temperature and voltage variations. In order to obtain a stable bias, a voltage drop of at least 1-2V is generally required across the bias resistor. In order to obt...

AI Technical Summary

Problems solved by technology

Compared with the traditional Darlington amplifier, this solution only eliminates the voltage drop on the bias resistor, but the device terminal voltage of the device Darlington amplifier itself does not change, so it cannot solve the problem of the high device terminal voltage of the Darlington amplifier. The problem, and because the self-bias part is connected to the circuit signal input terminal, it will cause a series of problems such as deteriorating the noise figure and deteriorating the standing wave coefficient of the input voltage.

Images