Dynamic magnetic information storage or retrieval – Head mounting – Disk record
Reexamination Certificate
1999-06-15
2001-07-03
Tupper, Robert S. (Department: 2652)
Dynamic magnetic information storage or retrieval
Head mounting
Disk record
Reexamination Certificate
active
06256172
ABSTRACT:
TECHNICAL FILED
The present invention relates generally to suspensions for supporting read/write heads over recording media. In particular, the present invention is an integrated lead head suspension having an active crosstalk attenuation conductor for reducing crosstalk interference between conductors formed on the integrated lead head suspension.
BACKGROUND OF THE INVENTION
Disk drives include disk drive suspensions for supporting read/write heads over information tracks of rotating disks. The well-known and widely used Watrous-type suspensions include a load beam having a mounting region on a proximal end, a flexure on a distal end, a relatively rigid region adjacent to the flexure and a spring region between the mounting region and the rigid region. An air-bearing slider that includes a read/write head is mounted to the flexure. The mounting region is typically attached to a base plate for mounting the load beam to an actuator arm. A motor which is controlled by a servo control system rotates the actuator arm to position the read/write head over desired information tracks on the disk. This type of suspension is used with both magnetic and non-magnetic disks.
Disk drive manufacturers continue to develop smaller yet higher storage capacity drives. Storage capacity increases are achieved in part by increasing the density of the information tracks on the disks (i.e., by using narrower and/or more closely spaced tracks). As track density increases, however, it becomes increasingly difficult for the motor and servo control system to quickly and accurately position the read/write head over the desired track. The use of head suspensions having microactuators or fine tracking motors has been proposed to overcome these problems. Such suspensions are disclosed in U.S. Pat. Nos. 5,657,188 and 5,898,544, which are assigned to Hutchinson Technology Incorporated, the assignee of the present application, and which are incorporated by reference herein.
However, the signals that are used to control the microactuators are relatively large (for example, having a peak voltage of about 30 V) compared to the sensitive signals (typically in the millivolt range) coming from the head slider. Since the microactuator control conductors (which conduct microactuator control signals between microactuator control circuitry and the microactuator) and the head slider conductors (which conduct the head slider signals) are typically routed near each other along at least a portion of the load beam, the larger microactuator control signals will tend to capacitively couple into the head slider signals. This crosstalk interference will tend to corrupt the sensitive head slider signals.
One known approach to reducing crosstalk interference between two signal-carrying conductors formed on a substrate that is used in a wide range of electrical applications is to form a conventional passive guard trace (sometimes referred to herein as a “passive crosstalk attenuation conductor”) in between the two signal-carrying conductors. The conventional passive crosstalk attenuation conductor is a conductor which is grounded, unterminated, or match terminated at its ends and runs between the two signal-carrying conductors. The conventional passive crosstalk attenuation conductor reduces the coupling between the two signal-carrying conductors, which reduces crosstalk interference therebetween.
Although conventional passive crosstalk attenuation conductors can reduce crosstalk interference to levels that are acceptable for some applications, conventional passive crosstalk attenuation conductors may not reduce crosstalk interference to acceptable level in other applications, such as when used on head suspensions having microactuator control conductors and head slider conductors. Thus, there is a continuing need for greater reductions in crosstalk interference between microactuator control conductors and head slider conductors.
SUMMARY OF THE INVENTION
The present invention can be embodied in any head suspension having first and second conductors conducting first and second signals, respectively. The head suspension according to the present invention includes an active crosstalk attenuation conductor formed on a load beam for conducting a crosstalk attenuation signal in order to reduce crosstalk interference between the first and second conductors. The crosstalk attenuation signal is a function of the first signal so that the electromagnetic field generated by the active crosstalk attenuation conductor reduces or cancels, at the second conductor, the electromagnetic field generated by the first conductor.
One embodiment of a head suspension according to the present invention includes a load beam having a distal end configured for receiving and supporting a head slider. A microactuator control conductor is located on the load beam for conducting a microactuator control signal between microactuator control circuitry and a microactuator mounted on the load beam. Also, a head slider conductor is located on the load beam for conducting a head slider signal between the head slider circuitry and the head slider. An active crosstalk attenuation conductor is positioned on the load beam for conducting a crosstalk attenuation signal to reduce crosstalk interference between the microactuator control conductor and the head slider conductor. Preferably the crosstalk attenuation conductor is located in between the microactuator control conductor and the head slider conductor along a portion of the load beam.
REFERENCES:
patent: 5862010 (1999-01-01), Simmons et al.
patent: 6088235 (2000-07-01), Chiao et al.
Faegre & Benson LLP
Hutchinson Technology Incorporated
Tupper Robert S.
LandOfFree
Active crosstalk attenuation conductor for an integrated... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Active crosstalk attenuation conductor for an integrated..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Active crosstalk attenuation conductor for an integrated... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2495843