Magnetoresistive reader for two-dimensional magnetic recording

A method for accessing a magnetic storage device, comprising:

• configuring a biasing circuit for an array of read heads according to whether the array of read heads is connected in series or in parallel;
• configuring the biasing circuit for current-biasing mode or voltage-biasing mode;
• passing the array of read heads over a data track on a storage medium;
• and
• amplifying an analog signal from each read head in the array of read heads in a preamplifier.

An apparatus for two-dimensional magnetic recording, comprising:

• a storage medium;
• an array of magnetoresistive read heads disposed adjacent the storage medium and spaced to read a data track;
• a plurality of leads connected to the array of magnetoresistive read heads;
• a plurality of bias circuits connected to the array of magnetoresistive read heads by the plurality of leads, wherein the plurality of bias circuits can be configured to independently bias each of the array of magnetoresistive read heads with the array of magnetoresistive read heads connected in series or in parallel, wherein the plurality of bias circuits comprise a push-pull current source connected to each of the array of magnetoresistive read heads;
• and
• a plurality of differential bias loop circuits, each connected to one of the push-pull current sources.