| 主权项 |
1. A test board, serving as an interface for testing a conference phone, comprising:
a plurality of test channel selectors, each of the test channel selectors receiving a plurality of test voltages transmitted by the conference phone and a first and second control signals, the test voltages being grouped into a plurality test voltage pairs and each of the test voltage pairs comprising two of the test voltages, and each of the test channel selectors directly selecting one of the test voltages in each of the test voltage pairs according to the first control signal for generating a plurality of selected voltages, and each of the test channel selectors selecting two of the selected voltages according to the second control signal for generating a first and second output voltages, wherein the first and second output voltages are transmitted to a test machine for testing the conference phone, and each of the test channel selectors comprises:
a first selection switch, receiving the first control signal and a first and second test voltage pairs of the test voltage pairs, and the first selection switch respectively selecting a first and a fourth selected voltage of the selected voltages in the first and second test voltage pairs according to the first control signal;a second selection switch, receiving the first control signal and a third and fourth test voltage pairs of the test voltage pairs, and the second selection switch respectively selecting a second and a third selected voltage of the selected voltages in the third and fourth test voltage pairs according to the second control signal;a third selection switch, receiving the second control signal and the first, second, third and fourth selected voltages, and the third selection switch selecting the first or the second selected voltage to generate the first output voltage according to the second control signal, and selecting the third or the fourth selected voltage to generate the second output voltage according to the second control signal. |
