Title:
JITTER MEASURING SYSTEM FOR DISK STORAGE DEVICE
Document Type and Number:
Japanese Patent JPS6476567
Kind Code:
A
Abstract:
PURPOSE:To measure jitter while reading data by finding the value of the jitter as the position of a latch register by which a read pulse is latched by transferring the read pulse stored in each stage of a shift register to a corresponding latch register. CONSTITUTION:An output pulse P is inputted to the first stage of shift register 2, and is shifted sequentially by a clock C generated from the output pulse P by a phase synchronizing oscillator 1. A latch pulse generation circuit 3 outputs a latch pulse R at every window period generated based on the clock pulse C from the phase synchronizing oscillator 1, and latches the value stored in each of the stages 21-25 of the shift register 2 in the latch registers 41-45 provided correspondingly. Then, the value of the jitter is found as the position of the latch registers 41-45 where the read pulse P is latched. In such a way, it is possible to measure the jitter of output easily and surely as reading out the data.
Inventors:
OKADA TOSHIO
Application Number:
JP23258887A
Publication Date:
March 22, 1989
Filing Date:
September 18, 1987
Export Citation:
Assignee:
FUJITSU LTD
International Classes:
G11B20/18; G11B19/06; G11B19/28; (IPC1-7): G11B19/06; G11B20/18
Attorney, Agent or Firm:
Hideo Takino (2 outside)