SU426301A1 - KEY TRANSISTOR AMPLIFIER WITH CURRENT CONNECTION - Google Patents

Description

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The invention relates to electronic systems of regulation, transformation and automation and can be used in stabilizers, inverters, etc.

Known transistor amplifiers with current feedback contain a current transformer, the secondary winding of which is closed at the input of the power transistor through an additional transistor. These amplifiers require the taking of a certain power from the control source in the open state of the amplifier.

The purpose of the invention is to reduce the power of the control source and increase the KP. booster. This goal is achieved by switching on the input of the additional transistor of an additional winding of the current transformer and connecting the input of the power transistor to the control source of the locking pulses.

The drawing shows a diagram of the proposed amplifier.

The amplifier contains a source of locking pulses 1, the signals from which are fed through a diode to the power transistor 2, in series with which the primary winding 3 of the current transformer 4 is connected.

6, controlled by the signal from the auxiliary winding 7 located on the transformer 4. The winding 8 is designed to reverse the magnetization reversal of the core of the transformer 4 due to the current flowing through it from the power supply U. The resistance 9 determines the magnitude of this current. Other ways of reversal of the transformer core 4 are possible.

The device works as follows. In the absence of a locking signal from source 1, transistors 2 and 6 open like an avalanche under positive feedback from primary winding 3 to windings 5 and 7, which control these transistors.

When a blocking signal is received from the source 1 at the power transistor 2, the latter is plugged. This leads to a decrease in the current flowing through the transistor 2 and the winding 3 and, as a consequence, to a change in the polarity of the voltages induced on the windings 5 and

7. These voltages cause the final locking of transistors 2 and 6.

After the transistors are locked, the current flowing through the winding 8, connected in opposite

winding 3, provides the remagnetization of the core of the transformer 4. Next, the processes are repeated. At the same time, in the entire range of load variation from the source 1 of the locking pulses, the power is practically not consumed, since for synchronization in the proposed device from the source of the locking imulses, only a voltage pulse is required for preliminary locking of the open power transistor, after which windings of the transformer 4, ensuring the final locking of the transistors 2 and 6 due to the power removed from the current transformer 4. This increases the efficiency booster.

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Subject invention

A current feedback key transistor amplifier containing an external pulse synchronization unit, a power transistor, a current transformer whose primary winding is connected in series to the amplifier power circuit, and the secondary winding is closed through an additional transistor to the input of the power transistor, characterized in that In order to increase the efficiency, the input of the additional transistor is connected to the additional winding of the current transformer, and the input of the power transistor is connected to the output of the specified unit.

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