Recording Front-End Systems Analysis

As data rates continue to increase, front-end design techniques and analysis must evolve in order to manage the transmission line effects and the parasitic effects of the transducer, electronics, and electrical interconnect. In addition, the complete write process contains linear and non-linear effects, which requires write signal wave-shaping for optimum performance. Data signal fidelity is maintained by proper termination at the read/write integrated circuit (IC), which is dependent on the read/write transducer´s impedance range. For writing, transmission-line termination techniques along with the write-driver electronics are utilized to induce the required overshoot for transitions in the write current waveform. For reading, the key aspects of signal-to-noise ratio (SNR) and bandwidth are the parasitic components at the read transducer and the input at the read amplifier. The Noise Figure (NF) of the front-end system can be modeled to include the parasitic effects along with the transmission losses of the interconnect. Here, we expound on design techniques and component values for the front-end system.