| 摘要 |
PROBLEM TO BE SOLVED: To provide a USB bus current limiting circuit that is convenient to carry around and available at low cost, and prevents a bus current from exceeding a limit current value. SOLUTION: The USB bus current limiting circuit, which limits using a predetermined limit current value a bus current supplied through the power line of a USB 20 by a USB-connected device connected to a host device by a USB, has detection means R1, 32, 34, 36 for detecting the bus current and generating a control signal whose level changes immediately before the detected current value exceeds the limit current value, and a gain adjusting means 38 for attenuating the signal level supplied to the load 28 of the USB-connected device, depending on the changes in the level of the control signal. COPYRIGHT: (C)2005,JPO&NCIPI
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