DATA AND SERVO SAMPLING IN SYNCHRONOUS DATA DETECTION CHANNEL

摘要

An analog to digital converter circuit (20) in a sampling data detection channel of a disk drive synchronously samples user data in a data track areas at a first quantization resolution and samples servo bursts from the spoke areas at a second quantization resolution effectively greater than said first quantization resolution. An offset circuit (60) provides a predetermined analog offset signal to a combining circuit (160, 170) which combines it with an incoming analog signal to provide a composite signal during a servo burst sampling interval. An analog to digital converter (180, 190) samples the composite signal during the servo spoke burst sampling interval, and synchronously samples the analog signal during a user data sampling interval. A digital averaging circuit (210) averages the servo spoke samples over a predetermined averaging interval to provide averaged burst samples having increased bit resolution.