Storage apparatus

• US 6,166,872 A
• Filed: 09/21/1998
• Issued: 12/26/2000
• Est. Priority Date: 03/20/1998
• Status: Expired due to Fees

• Current Assignee: Toshiba Storage Device Corp (Toshiba Corporation)
• Original Assignee: Fujitsu Limited
• Inventors: Uno, Hiroshi, Mitsunaga, Nobuyuki
• Primary Examiner(s): KIM, WON TAE C
• Application Number:
  US09/157,707
• Time in Patent Office: 827 Days
• Field of Search: 360/65, 360/46, 360/67
• US Class Current: 360/65
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence
• CPC Class Codes: G11B 5/035 Equalising
• CPC Class Codes: G11B 5/09 Digital recording
• CPC Class Codes: G11B 5/486 with provision for mounting or arranging electrical conducting means or circuits on or along the arm assembly
• CPC Class Codes: H05K 1/118 specially for flexible printed circuits, e.g. using folded portions

Abstract

A read signal from a head is amplified by a read amplifier disposed on a head actuator and is fed via a pair of read only transmission paths through an FPC to a control board. The read only transmission paths are provided with a compensation circuit consisting of an inductance and a resistor which are connected in parallel. The compensation circuit compensates for degradation of frequency characteristics of a read signal attributable to stray capacitance of the FPC and to stray capacitance on the control board side.

Claims

1. A storage apparatus comprising:

a head actuator for positioning a head relative to a disk medium;

a flexible printed circuit for electrically connecting said head actuator and a fixed side, said flexible printed circuit having a predetermined length required for a motion of said head actuator;

a read amplifier disposed on said head actuator side, for amplifying an analog read signal from said head;

a pair of read only transmission paths for feeding an output signal from said read amplifier via said flexible printed circuit to a control board; and

a compensation circuit disposed on said pair of read only transmission paths, for compensating for a degradation of frequency characteristics of said analog read signal attributable to stray capacitance of said flexible printed circuit and to stray capacitance on said control board side.

2. A storage apparatus according to claim 1, wherein

said compensation circuit includes an inductance and a resistor connected in series between said pair of read only transmission paths.

3. A storage apparatus according to claim 1, wherein

said compensation circuit includes an inductance and a resistor connected in series between said pair of read only transmission paths and includes a pair of terminating resistors each having one end connected to corresponding one of said pair of read only transmission paths and the other end connected to the ground.

4. A storage apparatus according to claim 1, wherein

said compensation circuit includes an inductance and a resistor connected to in series between said pair of read only transmission paths and includes a pair of terminating resistors each having one end connected to corresponding one of said pair read only of transmission paths and the other end connected to the ground and includes a pair of buffer amplifiers provided on said read only transmission paths, respectively, for eliminating stray capacitance on said control board side.

5. A storage apparatus according to claim 4, wherein

said buffer amplifier is an emitter follower circuit.

6. A storage apparatus according to claim 1, wherein

said compensation circuit is mounted on reception ends of said pair of transmission paths on said control board.

7. A storage apparatus according to claim 1, wherein an output circuit of said read amplifier is a read buffer circuit of open collector type.

8. A storage apparatus according to claim 1, further comprising:

a write amplifier disposed on said head actuator side, for feeding a write current into said head to thereby record data on said disk medium;

a pair of write only transmission paths through which write data from said control board are fed via said flexible printed circuit to said write amplifier; and

a pair of terminating resistors each having one end connected to corresponding one of reception ends of said pair of write only transmission paths on said write amplifier and having the other end connected to the ground.

9. A storage apparatus according to claim 1, further comprising:

a write amplifier disposed on said head actuator side, for feeding a write current into said head to thereby record data on said disk medium;

a first write modulation circuit disposed on said control board, for providing a parallel output of write data;

a parallel write transmission path through which parallel write data from said first write modulation circuit are fed via said flexible printed circuit to said head actuator side; and

a second write modulation circuit disposed on said actuator side, for converting parallel write data transferred from said parallel write transmission path into serial write data.

10. A storage apparatus according to claim 9, wherein

said first write modulation circuit mounted on said control board includes a scrambler and an RLL encoder, and wherein

said second write modulation circuit mounted on said head actuator side includes a parallel/series converter, a precoder and a write compensation circuit.