The 5.0 V pre-amplifier for HDD applications has been designed for five terminal, dual-stripe Magneto-Resistive (MR)-read/inductive write heads. The disks of the disk drive are connected to ground. To avoid voltage breakthrough between the heads and the disk, the MR elements of the heads are also connected to ground. The symmetry of the dual-stripe head-amplifier combination automatically distinguishes between the differential signals such as signals and the common-mode effects like interference. The latter are rejected by the amplifier.
• Designed for 10 dual-stripe MR-read/inductive write heads
• Current bias-current sense architecture
• Single supply voltage (5.0 V ±10%); a separate write drivers supply pin can be biased from VCC to 8 V +10%
• MR elements connected to ground (GND)
• Equal bias currents in the two MR stripes of each head
• On-chip AC couplings eliminate MR head DC offset
• 3-wire serial interface for programming
• Programmable voltage/current mode write data input
• Programmable high frequency zero-pole gain boost
• Programmable write driver compensation capacitance
• Programmable MR bias currents and write currents
• 1-bit programmable read gain
• Sleep, standby, active and test modes available
• Measurement of head resistances in test mode
• In test mode, one MR bias current may be forced to a minimum current
• Short write current rise and fall times with near rail-to-rail voltage swing
• Head unsafe pin for signalling of abnormal conditions and behaviour
• Low supply voltage write current inhibit (active or inactive)
• Support servo writing
• Provide temperature monitor
• Thermal asperity detection with programmable threshold level
• Requires only one external resistor.
• Hard Disk Drive (HDD).