CIRCUIT AND METHOD TO ACHIEVE SYMMETRICAL SWITCHING VOLTAGE OUTPUT OF WRITE DRIVER AND TO MATCH COMMON MODE FLEX IMPEDANCE

摘要

PROBLEM TO BE SOLVED: To provide a disk drive write driver capable of achieving minimum signal reflection and attaining a high data rate in association with a write operation. SOLUTION: A disk drive write driver (100, 200, 300) includes a current switch (Q0, Q1) having differential output impedance configured so as to match differential input impedance of a prescribed interconnection (106) connected to an inductive head (108) and common mode output impedance configured so as to match the common mode input impedance of the prescribed interconnection. When the current switch performs writing to the inductive head, the current switch is switched on in response to pseudo ECL logic input signals (102, 104) so as to produce near-ground common mode output voltages. COPYRIGHT: (C)2004,JPO