Push-pull voltage buffer with improved load capacity

The article considers a method of increasing the load capacity of high-linear push-pull voltage buffer devices built on bipolar transistors. Buffer devices are designed to match the impedance of the signal generator to the impedance of the load and are essentially power amplifiers and act as an impedance converter with high input and low output impedances with a voltage transfer factor as close to unity as possible. The most common is the construction of buffer devices based on operational amplifiers with deep feedback in the voltage follower mode. At the present time, special attention is also drawn to push-pull circuits of buffer devices, which are considered in this article. An important characteristic of buffer devices is the load capacity, and to improve it (reduce the output resistance) of such buffer devices, a method based on the introduction of a push-pull DC output amplifier into the circuit is proposed. It is able to provide high linearity of the transmission characteristics and the required speed. New methods of structural and functional organization of the core of precision buffer devices with high and very high input resistance and the output push-pull current amplifier with different amplification factors are proposed. A schematic analysis of the static characteristics of the specified nodes, input resistance, load capacity and current amplification factor was performed. It has been proven that this method allows to significantly improve the load capacity of the voltage buffer.