SU1580526A1 - Amplifier, class d - Google Patents

Abstract

The invention relates to amplifier technology. The purpose of the invention is to increase the average operating efficiency. At the output of the threshold element 1, pulses with varying duty cycle are formed. At the output of the additional low-pass filter 9 a constant voltage is generated, the value of which is directly proportional to the frequency of the input amplified signal. The frequency of the triangular voltage taken from the output of the integrating amplifier 7 is directly proportional to the voltage at the output of the additional low-pass filter 9. Thus, an increase in the clock period at a low frequency of the input signal leads to a decrease in switching losses and, consequently, to an increase in its average operating efficiency. 1 il.

Description

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The invention relates to an amplifier technique and can be used in low frequency amplifiers and converters.

The purpose of the invention is to increase the average operating efficiency.

The drawing shows a structured electrical circuit amplifier class D. i

Class D amplifier contains input-j threshold element t, analog switch 2, one-shot 3, inverter 4, key power amplifier 5, low-pass filter 6, integrated-amplifier 7, first Schmitt trigger 8, additional low-pass filter 9, second trigger Schmitt 10.

Class D amplifier works as follows.20

The low frequency voltage is supplied from the input source to the signal input of the input threshold element 1, where it is converted into square pulses with a variable duration of 25. The same voltage (variable frequency) is converted in the second Schmitt trigger 10, single-vibrator 3 and additional low-pass filter 9 into a constant voltage, the value of which is directly proportional to the frequency of the input voltage. The constant voltage goes to the first input of the analog switch directly, and to the second

threshold 1., where it is compared with the input voltage. From the output of the input threshold element 1, the duration-modulated rectangular pulses are amplified in the key power amplifier 5, and the low-frequency component is output at the output of the low-pass filter 6.

Thus, an increase in the period of the clock frequency at a low frequency of the input voltage leads to a decrease in switching losses and, consequently, to an increase in its average operating efficiency.

Claims (1)

Invention Formula A class D amplifier containing an input threshold element, an analog switch, a one-shot, an inverter, as well as a series-connected key power amplifier and a low-pass filter, so that, in order to increase the average | Tsneekspluatatsionny Efficiency, introduced in series are the integrating amplifier and the first Schmitt trigger, an additional low-pass filter and the second Schmitt trigger, the output of which is connected to the input of the one-shot, the output of the additional low-pass filter is connected to the lane. ,. „, - - ... “To the input of the analog switch, the input is through the inverter 4. In dependent-- and through the inverter - to the second input analog switch, the output of which is connected to the input of the integrating amplifier, the output of the input threshold element connected to the input of the key power amplifier, the reference input of the input threshold element 40 From the polarity of the control voltage at the output of the first Schmitt trigger 8, the analog switch 2 forms the voltage of one sign or another at the input of the integrating amplifier 7. The value of the frequency of the triangular voltage, taken from the output of the integrating amplifier 7, is directly proportional to the value of the control voltage of the output of the additional low-pass filter 9 and, therefore, to the frequency of the input voltage. The voltage of a triangular shape is fed to the input reference input 50 connected to the input of the first Schmitt trigger, the output of which is connected to the control input of the analog switch, while the input of the second Schmitt trigger is connected to the input of the input threshold element, and the output of the one-vibrator to the input of the additional low-pass filter of the threshold element 1., where it is compared with the input .contact. From the output of the input threshold element 1, duration-modulated square-wave pulses are amplified in the key power amplifier 5, and a low-frequency component is output at the output of the Iltra 6 low frequency. Thus, an increase in the clock period at a low input voltage frequency leads to a decrease in switching losses and, consequently, to an increase in its average operating efficiency. Invention Formula A class D amplifier containing an input threshold element, an analog switch, a one-shot, an inverter, as well as a series-connected key power amplifier and a low-pass filter, so that, in order to increase the average | Tsneekspluatatsionny Efficiency, a series-connected integrating amplifier and the first Schmitt trigger, an additional low-pass filter and a second Schmitt trigger, the output of which is connected to the one-shot input, the output of the additional low-pass filter are connected to connected to the input of the first Schmitt trigger, the output of which is connected to the control input of the analog switch, while the input of the second Schmitt trigger is connected to the input of the input threshold element, and the output of the one-shot to the input of the additional low-pass filter.