| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a voltage adjustment circuit for a hard disk. <P>SOLUTION: A voltage adjustment circuit for a hard disk includes a hard disk interface, a hard disk control chip, and a switch module. The hard disk interface comprises a first signal pin, a second signal pin, a first power source pin and a second power source pin. The hard disk control chip comprises a third signal pin and a fourth signal pin, and transmits a pair of differential signals to the first and second signal pins in read or write on the hard disk but does not transmit the differential signals otherwise. The switch module is connected to the third and fourth signal pins and a DC power source, and comprises a first terminal receiving a low level signal or a high level signal, and second to fifth terminals connected respectively to a first power source, a second power source, the first power source pin and the second power source pin. The switch module outputs the voltage of the first and second power sources to the hard disk interface when the first terminal receives the low level signal; but does not output the voltage of the first and second power sources to the hard disk interface otherwise. <P>COPYRIGHT: (C)2013,JPO&INPIT |
