| 摘要 |
PROBLEM TO BE SOLVED: To automate switching of two kinds of terminating resistances for synchronizing signal input. SOLUTION: This circuit is equipped with an analog switch 3 which selects a termination resistance 1 of 75Ωor terminating resistor 2 of 2.2 KΩ, a level detection part 7 which compares the input synchronizing signal levels of the terminating resistances 1 and 2 of interfaces obtained by the switch 3 at a start by a difference detection part 74 and discrcriminate their difference is large or small by a comparator 75, and a control part 8, which controls the switch 3 according to the large/small decision result of the level detection part 7, so that one of the terminating resistances 1 and 2 is set.
|
