5.0 V, 200 M-Bit/Sec PR-IV Hard Disk Drive Read Channel

The Motorola MC34250 is a fully integrated partial response maximum likelihood disk drive read/write channel for use in zoned recording applications. This device integrates the AGC, active filter, 7 tap equalizer, Viterbi detector, frequency synthesizer, servo demodulator, 8/9 rate (0,4/4) Encoder/Decoder with write precompensation and power management in a single 64 pin 10 mm x 10 mm TQFP package.

FEATURES:

? 50 to 200 MBPS Programmable Data Rate

? 800 mW at 200 MBPS and 5.0 V

? Channel Monitor Output

? Programmable AGC Charge Pump Currents with Different Values for Data and Servo Envelope Modes and Gain Gradient Mode

? Programmable AGC Peak Detector Droop Currents with Different Values for Data and Servo Envelope Modes

? Separate AGC Charge Pump Outputs for Data and Servo Modes

? Programmable Dual Threshold Qualifier or Hysteresis Comparator Type Pulse Detector for Servo Data Detection.

? ERD and Polarity Outputs for Servo Timing and Raw Encoded Data

? Integrated 7 pole 0.05° Equiripple Linear Phase Filter with Programmable Bandwidth from 5.0 MHz to 80 MHz and Different Values for Both Data and Servo Modes

? Programmable Symmetrical Boost from 0 to 10 dB and Different Values for Data and Servo Modes

? Programmable Asymmetrical Boost of Up to ±40 of Nominal Filter Group Delay in Both Data and Servo Modes

? 7 Tap Continuous Time Transversal Equalizer with 8 Bit Programmable Tap Weights and Integrated Decision Directed Sign–Sign Least Mean Squared Adaptation

? Internal Offset Cancellation Loops

? Fast Acquisition Data Phase Locked Loop with Zero Phase Restart

? Programmable Data Phase Locked Loop Charge Pump Current

? Integrated Soft Decision Viterbi Detectors with Programmable Merge References

? Integrated 8/9 Rate (0,4/4) Encoder and Decoder with Code Scrambler and Descrambler

? Programmable 2/4/8 Bit NRZ Data Interface

? Programmable Write Precompensation Delays Locked to the Frequency Synthesizer

? Differential PECL Write Data Outputs

? External Write Data Path for DC Erase or Other Non–Encoded Data

? Integrated Write Current DAC

? Programmable Power Management

? Bi–Directional Serial Microprocessor Interface

? Various Test Modes Controlled Via the Serial Microprocessor Interface