Title:
DISTINGUISHING CIRCUIT FOR DUTY RATIO OF SIGNAL
Document Type and Number:
Japanese Patent JP3148358
Kind Code:
B2
Abstract:
PURPOSE: To distinguish the control signal duty ratios at a plurality of steps by furnishing a counter and 2 DATA latch circuit, and counting borrow signals outputted by the counter.
CONSTITUTION: In the reproduction divisions of High or Low, count-up is made with the first clock pulses during one period of control signals, and the count value is latched in a DATA latch circuit 22. In the following division of control signals, count-down is made with the second clock pulses, and when borrow signal is generated by a counter 20, the count value latched in the DATA latch circuit 22 is preset on this counter 20. In the same manner the counts-down, borrow signal generating, and counter preset are made with a plurality of other clock pulses, and the period of clock pulses is set for each case so that the borrow signal generating timing is identical to a plurality of thresholds for distinguishing the duty ratio of the VTR controlling signals. What the control signals in one period contain, can be distinguished in correspondence to the frequency of borrow signal generation.
Inventors:
Shuichi Tobita
Application Number:
JP14012992A
Publication Date:
March 19, 2001
Filing Date:
April 30, 1992
Export Citation:
Assignee:
Sanyo Electric Co., Ltd.
International Classes:
G01R29/02; G11B5/027; G11B15/087; G11B15/52; G11B27/28; (IPC1-7): G01R29/02; G11B5/027; G11B15/087; G11B27/28
Domestic Patent References:
| JP63149877A | ||||
| JP3114067U |
Attorney, Agent or Firm:
Toshiyuki Maruyama (3 others)