| 摘要 |
PURPOSE:To obtain a variable rotation type device by inputting an index signal and latching output signals of (n) sets of comparators different in slice level at different delay timing, and switching a rotating speed in (n) stages. CONSTITUTION:An index signal (a) is inputted from an index sensor, and compared by comparators 1 and 2 with different slice levels V1 and V2. A delay circuit 4 inputs the low-order digit signal (c) of the output of the comparator 2 through an inverter 3 and outputs a delay signal (d) which is delayed by a specific time. A latch circuit 5 consists of a D type FF; the high-order digit signal (b) from the comparator 1 is inputted to a terminal and the delay signal (d) is inputted to a terminal CP. A rotation control circuit 6 receives a rotation switching signal (e) from the output terminal Q of the circuit 5 to switch the rotating speed of a spindle motor. Thus, one kind of floppy disk device is capable of writing and/or reading binary information to and/or out of plural media which differ in recording density. |
