JPS628Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a magnetic recording/reproducing circuit, and particularly relates to an improvement of a reproducing circuit of a magnetic recording/reproducing system in which data may be generated.

In conventional reproducing circuits, the differentiated analog waveform is shaped into a rectangular wave, but if a pulse is generated by a third harmonic or the like, abnormal data will be produced.

An object of the present invention is to provide a regeneration circuit that has small bit deviations and eliminates spurious pulses.

That is, magnetic recording is characterized in that a circuit that generates a one-shot in the same direction is provided at the data inversion section, and the presence or absence of correct data inversion is determined after a certain period of time using one one-shot circuit regardless of the data inversion direction. The gist of this paper is the reproduction circuit.

Next, embodiments of the present invention will be described using the drawings.

FIG. 1 is a block diagram of a reproducing circuit according to an embodiment of the present invention, and FIG. 2 shows waveforms of each circuit.

A magnetic head 1, a preamplifier 2 that amplifies the waveform read out by the magnetic head, a differentiating circuit 3, a differentiating circuit 3
A rectangular wave shaping circuit 4 that shapes the differentiated waveform a (see Figure 2) into a rectangular wave, a delay circuit 5 that delays this rectangular wave, and an exclusive OR of the original rectangular wave and the delayed rectangular wave. An XOR circuit 6, a one-shot generating circuit 7 that generates a one-shot at the rising edge of this output signal c, and a D-type flip-flop that synchronizes at the falling edge of the output signal d of this one-shot generating circuit and uses the original rectangular wave as data. It consists of 8 parts.

Note that the time constant of the one-shot generating circuit 7 is smaller than the pulse interval of the output waveform of the rectangular wave shaping circuit 4.
Selected to be larger than the pulse width of the generated noise.
Further, the delay time of the delay circuit 5 is equal to the pulse width of the output signal C of the XOR circuit 6.

Data is read out by the magnetic head 1 and reproduced through the preamplifier 2 and the differential circuit 3 as shown in FIG. 2a. If a step occurs at this time, the rectangular wave shaped by the rectangular wave shaping circuit 4 includes a springing pulse as shown in FIG. 2b. XOR circuit 6
Accordingly, at the portion where the rectangular wave b is inverted, a pulse c in the same direction is generated without causing a bit shift due to a difference between the rising and falling edges of the rectangular wave b. The rise of this signal c causes the one-shot generating circuit 7 to generate a one-shot pulse of the length to be removed, as shown in FIG. 2d. By synchronizing the original rectangular wave b with the falling edge of this one-shot pulse d,
As shown in the figure, a rectangular wave from which the outgoing pulse has been removed is reproduced.

With the above-described configuration, the reproducing circuit of the present invention has a simple circuit, and the bit shift due to the difference between the rising edge and the falling edge of data is small, and the overflowing pulse can be removed.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a reproducing circuit according to an embodiment of the present invention, and FIG. 2 is an output waveform diagram showing the operation of each point shown in FIG. 1: Magnetic head, 2: Preamplifier, 3: Differential circuit, 4: Square wave shaping circuit, 5: Delay circuit, 6:
EXOR circuit, 7: One shot generation circuit, 8: D
Type flipflop.

Claims (1)

[Scope of utility model registration request] In a magnetic recording/reproducing circuit that amplifies, differentiates, and waveform-shapes a signal read from a head, a circuit that creates an exclusive OR signal of the waveform-shaping output signal and a delayed version of the signal. A magnetic recording/reproducing circuit comprising: a one-shot generating circuit that is triggered by an output signal pulse of the circuit; and a flip-flop circuit that takes in the waveform-shaped output signal at the falling edge of the output signal pulse of the one-shot generating circuit.