The FIR filter is equipped with 4-tap, 6-bits dual input and 7-bits dual output, designed to fine-tune the EPR4 equalization of a Read/Write channel for hard-disk drive. It has a filter coefficient adaptation loop, able to optimize the 6 bits taps coefficients.

Features:

• 6 bits signed input, paired( 2 samples per clock)
• 6 bits signed coefficients
• 7 bits signed output, paired ( 2 samples per clock )
• 400 MHz operation in 0.29mm CMOS technology ( 800 Ms/s )
• 4 taps, 5 coefficients ( middle one fixed )
• independently adapted coefficients using LMS algorithm with error sign and input amplitude
• programmable adaptation rate
• every coefficient has an enable bit for adaptation