SU1256146A1 - M-dm type direct-current amplifier - Google Patents

Abstract

This invention relates to a radio and electrical measuring technique. The purpose of the invention is to improve accuracy. The device contains input and output low-pass filters (LPF), 1 and 9, modulator 2, alternating voltage 3, voltage isolation unit 4, rectifier (B) 5, key | {6 and 7 , diff. 8, rr 10 of carrier frequency and phase discriminator (PD) 11, consisting of a generator of 12 pulses, diff. the chains 13, the key 14, the inverter 15 and the RS flip-flop 16. The modulated alternating voltage obtained at the output of the modulator 2 is amplified and, after galvanic separation, is fed to the input B 5 and the input PD 11, to the other input of which -pa 10. When put, (negative) polarity of the input voltage of the device, the output signals of PD 11 close (open) the key 6 and the output B 5 is connected (disconnected) to the non-inverting input diff. 8, and the key 7 open (close) and output B 5 is disconnected (connected) from the inverting Log-on dif.u l 8. In this case the output DEVICE through LPF 9 is supplied put (otritsat). constant output voltage proportional to input voltage. The goal is achieved by the introduction of B 5 and PD 11. 1 Cp f-crystals, 1 ill. (O (L N9 cl f 4iii 02

Description

The invention relates to radio and electrical measuring equipment and can be used in information-measuring devices and automatic control and measurement systems.

The purpose of the invention is to increase accuracy.

The drawing shows a structural diagram of an M-DM type DC amplifier.

DC amplifier type M-DMY contains low pass filter 1, modulator 2, alternating voltage amplifier 3, galvanic separation unit 4, rectifier 5, keys 6 and 7, differential amplifier 8, low pass output filter 9, generator 10 carrier frequencies, a phase-5 discriminator 11, a driver of 12 pulses, a differentiating chain 13, an additional switch 14, an inverter 15 and an RS flip-flop 16.

The amplifier works as follows.

The input DC voltage through the filter 1 is fed to the input of the modulator 2 and modulated by a signal from the output of the generator 10. The resulting modulated alternating voltage of the positive amplifying pulse to the R input of the RS flip-flop 16 is switched. The switch 6 closes and connects the output of the rectifier 5 to the non-inverting input of the differential amplifier 8, and the switch 7 opens and disconnects the output of the rectifier 5 from the inverting input of the differential amplifier 8. At the output of the DC amplifier, the output constant 9 is outputted through the output amplifier 9 voltage proportional to the input.

When the polarity of the input DC voltage is changed, the DC-amplifier and the S-input of the RS flip-flop 16 receive a positive pulse. The key 6 opens, the key 7 closes and connects the output of the rectifier 5 to the inverting input of the differential amplifier 8.

At the output of the low-pass filter at this moment, a negative DC voltage proportional to the input voltage appears.

Claims (2)

Claims 1. DC amplifier type 3 and a sub-25 M-DM unit containing a low-pass filter connected in series, a modulator, an AC voltage amplifier, a galvanic separation unit, as well as an output low-pass filter, a carrier frequency generator, the output of which is connected to the corresponding input modulator, and two switches, the inputs of which are combined and connected to the output of the galvanic separation unit, and the outputs through a differential amplifier are connected to the input of the output low-pass filter, characterized in that neither the accuracy in it, a rectifier is inserted between the output of the galvanic separation unit and the key inputs, and the key control inputs are connected to antiphase ones To the input of the rectifier 5 and the input of the phase discriminator 11. To the other input of the phase discriminator 11 a alternating voltage is supplied from the output of the generator 10. The shaper 12 forms a sequence of pulses of the same amplitude from the alternating voltage supplied to the input of the phase discriminator 11 , and the amplitude of these pulses does not depend on the change in the magnitude of the input voltage. From the output of the driver 12, the pulses are fed to the input of the additional key 14 through the differentiating chain 13. The control input of the additional key 14 is energized from the generator 10. At the output of the additional switch 35 Part 14 appears to be differentiated by the im ... exits of the introduced phase discrimination of positive or negative polarity. Positive-field pulses appear when the leading edge of the output pulses of the driver 12 and the open state coincide in time, the first and second inputs of which are connected to the output of the carrier frequency generator and the output of the galvanic separation unit, respectively. 2. The amplifier according to claim 1, characterized in that. No additional key 14, which corresponds to the 45 phase discriminator is made on a pulse driver, a differentiating chain, an auxiliary key, an inverter and an RS flip-flop, the input of the pulse shaper is the second input of the phase discriminator, and the forward through For example, the positive polarity of the input voltage of the DC amplifier. Negative polarity pulses appear when the trailing edge of the output pulses coincides in time. a pulse driver, a differentiating chain, an auxiliary key, an inverter and an RS flip-flop, the input of the pulse shaper is the second input of the phase discriminator, and the forward through shaper 12 and open state 50 differentiating chain connected an additional switch 14, which corresponds to the negative polarity of the input voltage of the dc amplifier. From the output of the additional key 14, pulses are applied to the R input of the RS flip-flop 16 and through the inverter 15 to the S input of the specified flip-flop. On the arrival of the front front per55 to the input of the additional key, the control input of the additional key is the first input of the phase discriminator, the output of the additional key is connected to the R input of the RS flip-flop directly, and through the inverter to the S input, the outputs of the RS flip-flop are the output of the phase discriminator. a positive pulse to the R input of the RS flip-flop 16 is switched. The switch 6 closes and connects the output of the rectifier 5 to the non-inverting input of the differential amplifier 8, and the switch 7 opens and disconnects the output of the rectifier 5 from the inverting input of the differential amplifier 8. At the output of the DC amplifier, the output constant 9 is outputted through the output amplifier 9 voltage proportional to the input. When the polarity of the input DC voltage is changed, the DC-amplifier and the S-input of the RS flip-flop 16 receive a positive pulse. The key 6 opens, the key 7 closes and connects the output of the rectifier 5 to the inverting input of the differential amplifier 8. At the output of the low-pass filter at this moment, a negative DC voltage proportional to the input voltage appears. Claims 1. DC amplifier type  the outputs of the input phase discriminator, the first and second inputs of which are connected to the output of the carrier frequency generator and the output of the galvanic separation unit, respectively. 2. The amplifier according to claim 1, characterized in that.   phase discriminator is made on   phase discriminator is made on a pulse driver, a differentiating chain, an auxiliary key, an inverter and an RS flip-flop, the input of the pulse shaper is the second input of the phase discriminator, and the forward through differentiating chain connected 55 to the input of the additional key, the control input of the additional key is the first input of the phase discriminator, the output of the additional key is connected to the R input of the RS flip-flop directly, and through the inverter to the S input, the outputs of the RS flip-flop are the output of the phase discriminator.