Influence of Parasitic Capacitance on Single and Dual 2-D Magnetic Recording Read Head Performance

Abstract

The parasitic capacitance of the reader affects performance through signal-to-noise ratio (SNR) in single readers and through crosstalk in dual 2-D magnetic recording readers. In a single reader, the majority of the capacitance is not from shield-to-shield capacitance but instead from lead-to-shield capacitance. The low-pass filtering of the reader circuit leads to an equalized SNR that depends on the parasitic capacitance. In a dual reader, the capacitance between the outer shields must be considered in addition to the capacitance between the inner shields in order to model accurately the crosstalk. Finite-element electromagnetic models and lumped element circuit models are validated with RF experiments on real heads.