US 8,508,876 B2 · Proximity sensing system

Abstract

A data storage system for detecting a location of a head relative to a magnetic media is described. This system comprises arms, a preamplifier circuit coupled to the arms for controlling the arms, a proximity sensing system positioned within the preamplifier circuit, the proximity sensing system comprising: an input stage for transmitting an input sense signal; a programmable gain stage coupled to receive the input sense signal and operative for transmitting a gain signal in response to receiving the input sense signal; a multiplexer coupled to receive the gain signal and at least one control signal, the multiplexer operative for transmitting a multiplexed signal; a detector coupled to receive the multiplexed signal and a second control signal, the detector operative for transmitting an output signal; wherein an amplitude associated with the output signal enables detecting the location of the head.

Claims9

Dependent claims

A proximity sensing system for determining proximity of a head to a magnetic media, comprising:

A. input circuitry having input leads, output leads, and bias circuitry connected between the input leads and output leads;
B. a bias digital to analog converter (DAC) having outputs coupled to the bias circuitry;
C. an offset DAC having an output;
D. subtractor circuitry having inputs coupled to the outputs of the input circuitry and to the output of the offset DAC and having difference outputs;
E. an amplifier having inputs coupled to the outputs of the difference outputs and an amplified signal output;
F. a filter having an input coupled to the amplified signal output and having a filtered signal output;
G. a track and hold circuit having an input coupled to the filtered signal output and having an output;
and
H. a decision circuit having an input coupled to the output of the track and hold circuit and an offset output coupled to an input of the offset DAC.

6 more elements

Dependencies are inferred from the claim text.

Proximity sensing system

Life of this patent

Proximity sensing system

Life of this patent

Abstract

Claims9