JPH01118284A - Semiconductor integrated circuit device for floppy disk drive - Google Patents

Abstract

PURPOSE:To realize miniaturization and light weight and to reduce the influence of a stray capacitance, etc., by incorporating respective circuits for recording, reading and control in the same semiconductor integrated circuit and arranging a center tap output power source terminal interposing a high voltage system power source terminal. CONSTITUTION:A read circuit part 100, a write and erasure circuit part 200 and a control circuit 300 to control a system required for a floppy disk drive equipment are incorporated in one semiconductor integrated circuit. Also, in the write and erasure circuit 200, the center tap output power source terminals (CT0 and CT1) 18 and 20 to perform the alternative selection of two magnetic heads and the switching of readout and write interposing a high voltage system source voltage terminal (VBB) 19 to supply the source voltage of a high voltage system to the magnetic head are arranged, which realizes the miniaturization and the light weight and also, the influence of the stray capacitance, etc., on a board wiring can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an FDD in which a write/read circuit for a floppy disk drive (FDD) and a control circuit for other systems of the FDD are incorporated into one semiconductor integrated circuit.
The present invention relates to a semiconductor integrated circuit device for DD.

[Prior art]

Conventional circuits of this type have the functions necessary for FDD.
It was composed of L, TTL, and discrete elements.

However, in such a conventional circuit, LSTTL, T
In order to commercialize products using a large number of TL and discrete elements, the number of external parts increases, leading to increased costs.
There were disadvantages such as: ■ Increased man-hours, ■ Inability to reduce size and weight, ■ Inability to save labor, and large variations in equipment.

[Summary of the invention]

The present invention has been made to eliminate the drawbacks of the above-mentioned prior art, and incorporates a recording circuit and a reading circuit, which are the main functions of an FDD device, and a logic control circuit for controlling other systems necessary for the above device. It is built into a semiconductor integrated circuit and is made smaller and lighter by arranging the center tap output power terminal across the high-voltage power supply terminal.

The purpose of the present invention is to provide a semiconductor integrated circuit device for FDD that can reduce man-hours and costs, reduce device variations, and reduce the effects of stray capacitance on board wiring. There is.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

The drawing shows one embodiment of the present invention. In the drawing, 100 is a reading circuit section (R'EAD CIRCUIT) for reading the contents recorded on the disk, and this reading circuit section 100 is a pulse generator 1
01, 104, D flip-flop 102, one-shot multi-by-break 103, comparator 1051, branch circuit 106, read amplifier 107, and matrix circuit 1
08. Also, this reading circuit 100
As an external terminal, the one-shot external component connection terminal (ONE 5) IOT COMPONII! NTS)
2, 3, 4, 5, External component connection terminal for differential circuit (DIFFERENTIATOR COMPONEN)
TS) 6.71 has a branch circuit input terminal (ACTIVB DI
FFERENTIATORINPUT) 8. 9,
Read amplifier output terminal (AMPLIFIHR0UTPU
T) 10, 11, Read amplifier gain adjustment terminal (
OFFSET DECOUPLING) 12. 1
3. Head 1 terminal ()IEAD 1) 14. 15
have. Note that terminal 1 is a non-connection terminal (
NC).

Further, 200 is a write/erase circuit section (recording circuit) for erasing information on the front of the disk surface before recording data on the disk, and for recording a signal according to input on the disk. The erasing circuit section 200 is
Write amplifier 201, flip-flop FF-1, write current setting circuit 202, common driver 203.5
■Detection circuit 204, erase circuit 205, one-shot multi-by-break O/S-1, O/S-2, gate G30
．． G31. G33 and a matrix circuit 108. And this write/erase circuit 200
is the head 0 terminal (H1l!AD) as an external terminal.
O) 16. 1? , a common driver terminal (center tap output power supply terminal) (CTO) for selectively selecting two heads and switching between reading and writing.
, CTI) 1B, 20, high voltage system (12V) for magnetic head
High-voltage system power supply voltage terminal (VB
B) 19, Earth terminal (GND) 21 to 25, Erase circuit output terminal (ERASE) 26, Write current setting terminal (CURRENT ADJ) 27, and External component connection terminal for one shot (ONE 5HOT-1, -2)
) 28. It has 29.

Reference numeral 300 is a control circuit unit for controlling the system necessary for FDD equipment, and this control circuit unit 300 includes one-shot multi-by-breaks 0/S-3 to O/S-5, flip-flops FF-2, -3 , and each gate. Further, in this control circuit section 300, 31
, 32 and 34 are external component connection terminals (ONE 5HOT-3, -4, -5) for setting the time constant of one-shot multi-by-break O/S-3, -4, -5, respectively, and 33 is a 5V Vcc terminal. , 35 is a reset terminal ([) when the power is turned on, 36 is a voltage control output terminal (VQLTAG
), 37 to 40 are stepper drive output terminals (STEPPERDRIVER), and 41 is a track O sensor terminal (TRAC) for checking whether the head is in the trunk O position (OSll!N5O).
R), 42 is an FPT sensor terminal (FPTSENSOR) for detecting whether or not recording is possible on the disc, 43 is an index sensor terminal (INDEX 5ENSOR) for checking the rotational state of the disc, 44 Bin:
t--s output 4 (■n mouthpiece), 45 is a non-connection terminal, 46 is an index terminal (m) that outputs an output status signal indicating whether the disk is rotating normally, 4
7 is a drive select terminal (■■"π117m) for selecting the floppy disk drive unit, 48
49 is a step terminal (dish) for moving the head in track; 50 is a write data terminal (n) for writing data; 51 ~55 is the ground terminal (GND), 56 is the write gate terminal (■1>) for selecting reading, reading, or writing, and 57 is the T/7 O terminal for outputting a signal when the trunk becomes O. (ffi), 58 is a write protect terminal (W'F7πff1) for outputting a recording operation permission signal, 59
Reference numeral 60 indicates a read data terminal (r) for outputting a reading output of the recorded contents of the disc, and 60 indicates a side 1 terminal (correction stage) for selecting 0°1 of the disc.

The control circuit section 300 controls the drive select, direction, step, write data, write gate, side 1. Index sensor, FPT sensor,
and a control input circuit section having respective terminals of a track O sensor and an index.

It is divided into an output circuit section having write protect, track O9, and read data terminals.

Note that in the figure, the * mark indicates that the output terminal is an open collector.

As described above, according to this embodiment, the logic circuit that controls the system necessary for the FDD device, including the reading and writing circuits, is incorporated into one semiconductor integrated circuit.
External parts and product board area are reduced, reducing man-hours and costs.

At the same time, it can be made smaller, lighter, and more labor-saving, resulting in a significant reduction in the cost of the product. Furthermore, variations in device products can be suppressed and reliability can be improved.

In addition, since the center-tap output power terminal is provided across the high-voltage system power supply voltage terminal, there is no fear that the power supply wiring will be formed to straddle each other on the printed circuit board on which this integrated circuit device is mounted. This has the effect that the external wiring is organized and the influence of stray capacitance on the board wiring can be reduced.

〔Effect of the invention〕

As described above, according to the present invention, a recording circuit and a reading circuit, which are the main functions of an FDD device, and a control circuit for controlling a system necessary for the device are incorporated into one semiconductor integrated circuit. In addition, the center-tapped output power terminal is placed across the high-voltage power supply terminal, making it possible to reduce size and weight, reduce man-hours, reduce costs, and reduce device variations. This has the effect of reducing the effects of stray capacitance, etc.

[Brief explanation of the drawing]

The drawing is a configuration diagram of a semiconductor integrated circuit device for FDD according to an embodiment of the present invention. 100...reading circuit section, 200...writing/
Erasing circuit section (recording circuit), 300... control circuit section, 1
8.20...Common driver terminal (center tap output power supply terminal), 19...High voltage system power supply voltage terminal.

Claims (1)

[Claims] (1) A semiconductor integrated circuit device for a floppy disk drive, which includes a recording circuit for recording signals according to input on the floppy disk, a reading circuit for reading the contents recorded on the floppy disk, and a floppy disk drive device. A control circuit for controlling the system required for the magnetic heads is built into the same semiconductor integrated circuit, and a high-voltage power supply terminal for supplying high-voltage power supply voltage to the magnetic heads is sandwiched between the two heads. A semiconductor integrated circuit device for a floppy disk drive, characterized in that it is provided with two center tap output power terminals for selective selection and switching between reading and writing.