PURPOSE: To remarkably decrease the number of pins in the case a detector is included in an IC by counting the difference between the present phase alteration degree and the previous phase alteration degree for every sampling and sending out the results.
CONSTITUTION: A differential circuit 31 takes in the phase alteration degree for every sampling pulse SP, keeps the phase alteration degree taken in for the previous sampling pulse SP as a reference to the present phase alteration degree, computes the difference between the present phase alteration degree and the previous phase alteration degree, and sends out the result to an A/B phase converting circuit 20 and a selector 33. Standard clock and divided clock frequencies are supplied to the selector 3 3 from input terminals T14-T17 through a divider and one of these frequencies is supplied automatically to a circuit 20 as a clock signal based on the input data D7, D6. As a result, the difference data for every sampling pulse SP supplied to the circuit 20 is converted into A-phase and B-phase signals, two-phase signals with 90-degree different phase are sent out of output terminals T4, T5, and thus the position data is displayed on a display apparatus.
| JPS60244814 | OPTICAL TYPE POSITION DETECTOR |
| JPH06105174 | [Title of Invention] Encoder |
MATSUYAMA YASUHIKO
MAEJIMA HIDEO
