JPH0718175Y2 - Full wave rectifier circuit - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a full-wave rectifier circuit.

[Prior Art] FIG. 4 (1) is a block diagram of a conventional full-wave rectifier circuit.
FIG. 2B is a circuit diagram thereof, and FIG. 5 is a signal waveform diagram of each part.

This full-wave rectification circuit is composed of an absolute value circuit 7 and an integration circuit 8. The absolute value (both waves) of the input signal S ₁₁ is detected by an operational amplifier and a diode, and the capacitor rectifies (integrates).

[Problems to be Solved by the Invention] The conventional full-wave rectifier circuit described above has the following drawbacks.

In FIG. 4 (2), the output S ₁₃ when the condenser C is not attached has the waveform shown in FIG. 5 (2), and when the condenser C is attached, the output is as shown in FIG. 5 (3). It becomes a rectified waveform. Here, as a matter of course, when the value of C, that is, the capacitance is increased, the integration effect is increased and the ripple content value of the rectified waveform is decreased. However, due to the integration effect, as shown in the comparison between (2) and (3) in FIG. 5, the fidelity deteriorates due to the delay of the waveform. Since the ripple amount and the fidelity of the waveform are in a contradictory relationship, the conventional circuit has determined the capacitance value of the capacitor C by making the compromise point between them the optimum value. However, it is natural that an output that does not have a ripple content and a waveform delay is required with respect to the waveform that should be obtained originally.

An object of the present invention is to provide a full-wave rectification circuit which has a small amount of ripples, a delay, and a high-fidelity rectified output.

[Means for Solving the Problems] The full-wave rectifier circuit of the present invention is a phase shifter that advances or delays the phase of a sinusoidal AC burst signal that is an input signal by 90 °, and outputs an absolute signal and a phase shifter of the input signal. First and second absolute value circuits that output the absolute value signals of the signals, respectively, first and second integration circuits that smooth the absolute value signals of the first and second absolute value circuits, and the first It has an average value circuit which outputs an average signal of the output of the integrating circuit and the output of the second integrating circuit.

[Operation] The absolute value signals of the first and second absolute value circuits have twice the frequency of the input signal and the output signal of the phase shifter, respectively. Therefore, since the phase shifted by 90 ° doubles the frequency, both absolute value signals are shifted by 180 °. Therefore, a rectified output that does not include a ripple component is obtained by passing the sine wave ripple whose frequency is twice that of the output signals of both integrator circuits and whose phases are shifted from each other by 180 °, and which passes through the average value circuit.

Here, since the integration time constant for rectification may be a small value such that the ripple component remains as a sine wave, there is almost no delay in the rectified output with respect to the input signal.

[Embodiment] Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of a full-wave rectifier circuit showing an embodiment of the present invention, and FIG. 2 is a waveform diagram of signals of respective parts thereof.

This full-wave rectifier circuit includes a phase shifter 1 that delays the phase of an AC signal S ₁ that is an input signal by 90 °, an absolute value signal S ₃ of the input signal S _{1, and} an absolute value signal S ₂ of an output signal S ₂ of the phase shifter 1. ₄ an absolute value circuit 2 and 3 and outputs respectively, the absolute value signal S ₃ of the absolute value circuit 2, S ₄ and an integration circuit 4 and 5 respectively smooth, integral with the output S ₅ of the integrating circuit 4 circuit 5 Output S ₆ mean value signal S ₇
And an average value circuit 6 for outputting

The output signals S ₅ and S ₆ of the integrator circuits 4 and ₅ have the same frequency as that of the input signal S ₁ and are equal DC voltages including sine wave ripples whose phases are shifted by 180 °. What is important here is that the integration time constants of the integrator circuits 4 and 5 are not values for completely converting the signals into direct current, but values for which ripple components remain as sine waves as shown in the figure. If the direct current component of the signals S ₅ and S ₆ is e _O and the amplitude of the ripple component is e _A , the signal S ₅ is
e _O + e _A sin (ωt + θ), the signal S ₆ is e _O + e _A sin (ωt +
π + θ). These two S ₅ and S ₆ are connected to the average value circuit 6
A signal S ₇ composed of a direct current voltage component e _O can be taken out by passing through.

As described above, according to the present embodiment, it is possible to obtain the DC output S ₇ that does not include the ripple component, and further, as described above, the integration time constant for rectification can be minimized, and the waveform can be output with good fidelity. Can be done.

Note that the phase shifter 1 is the same even if the phase of the input signal S ₁ is advanced by 90 °.

FIG. 3 is a circuit diagram of a specific example of the full-wave rectifier circuit and corresponds to the block diagram of FIG.

The third circuit is a general existing circuit using an operational amplifier, and the description of the operation thereof is sufficient, and the description thereof is omitted here.

[Effect of the Invention] As described above, the present invention provides a signal obtained by full-wave rectifying a sine wave AC burst signal and the sine wave AC burst signal.
By taking the average value with the full-wave rectified signal that is phase-shifted by 90 °, it is possible to reduce the amount of ripples and obtain a rectified output with good waveform fidelity.

[Brief description of drawings]

FIG. 1 is a block diagram of a full-wave rectifier circuit showing an embodiment of the present invention, FIG. 2 is a waveform diagram of signals of respective parts, and FIG. 3 is a circuit diagram of a specific example of the full-wave rectifier circuit of the present invention. Figure 4 (1),
(2) is a block diagram and a circuit diagram of a conventional full-wave rectifier circuit, respectively, and FIG. 5 is a waveform diagram of signals of respective parts. 1 ... Phase shifter 2, 3 ... Absolute value circuit 4, 5, ...
… Integrator circuit, 6 …… Average value circuit, S _{1 to} S ₇ …… Signal.

Claims (1)

[Scope of utility model registration request] 1. A phase shifter for advancing or delaying the phase of a sinusoidal AC burst signal as an input signal by 90 °, and an absolute value signal of an input signal and an absolute value signal of an output signal of the phase shifter. A second absolute value circuit, first and second integrator circuits that smooth the absolute value signals of the first and second absolute value circuits, respectively, an output of the first integrator circuit and an output of the second integrator circuit Full-wave rectification circuit having an average value circuit for outputting the average value signal of