Patent ID: 8503127

Claim:
A circuit for providing a control current to control a write current amplitude in a magnetic media drive, comprising: an output circuit for providing said control current of amplitude dependent on a bias voltage; a bias current path to provide said bias voltage to said output circuit; a current diverting circuit connected to divert current from said bias current path; a circuit for providing a programmable ramp voltage in response to a degauss enable signal; and a voltage-to-current converter receiving said programmable ramp voltage, and being connected to said current diverting circuit to divert current from said bias current path at a rate determined by said programmable ramp voltage, whereby said bias voltage and said write current decay according to said programmable ramp voltage, wherein said circuit for providing a programmable ramp voltage in response to a degauss enable signal comprises a current source, a capacitor in series with said current source, and a switch in parallel with said capacitor operated by said degauss enable signal to open to allow said current source to charge said capacitor to produce said ramp voltage thereacross, wherein said write current decay is substantially a substantially linearly decaying pulse, wherein each pulse is also itself linearly decaying, and wherein said write current is also substantially independent of a beginning write current amplitude.