| 摘要 |
<p>Seizure circuit with a low-loss current-feeding device for the incoming c-wire of a telecommunications device with a switching controller designed as a switchable constant-current source. In the case of an unseized c-wire, a test resistor (R1) is first inserted in the switching circuit, following identified seizure the switching controller is activated instead of the test resistor and the latter is de-activated. After the test phase, only the hold current is emitted by the switching controller. <IMAGE></p> |
