Disk drive write driver with boosting circuit to improve output voltage swing
US7035028B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 2004 |
| Grant date | Apr 25, 2006 |
| Priority date | — |
| Expiry date | May 12, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02M3/073
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A write driver driving a write current through a head connected to the write head by an interconnect. The write driver includes a circuit matching output resistance to the odd characteristic impedance of the interconnect and a voltage boosting circuit. The voltage boosting circuit in connected between a high voltage reference or supply voltage and a low voltage reference, and includes a current source, such as a MOS transistor, connected to the input node of a capacitor. During the overshoot duration, the current source operates at saturation to generate a pulsed current with an amplitude of half the load current. The circuit includes another transistor in series with the current generator between the capacitor and the driver output. A forward bias diode is connected between the capacitor output node and high voltage reference and enters reverse bias during overshoot duration swinging the driver output voltage above supply voltage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.