A 240 Mb/1 W CMOS EPRML read channel LSI for hard disk drives

A 3.3 V 1 W 240 Mb/s EPRML read/write channel LSI for hard disk drives uses 0.4 /spl mu/m CMOS technology. Analog implementation of the entire channel has lower power consumption, because it eliminates the power-consuming A/D converter. It requires a BiCMOS process for precise analog circuits. The digital approach uses an A/D converter that provides precise digital signal processing. Here, the CMOS digital approach is used because it has potential for advanced signal processing. Two important issues are 1) reduction of the power consumption of extensive digital circuits and the A/D converter, and 2) breaking the speed bottleneck of the A/D converter. To reduce power consumption, a 0.4 /spl mu/m CMOS process with 3.3 V supply voltage is used. In addition, 3.3 V analog CMOS circuits are used, such as a gain controlled integrator for 7th-order equiripple active filters and an analog PLL.