Patent ID: 7552351

Claim:
A system for controlling sequential startup of hard disks applicable to an electronic system comprising a first set of hard disks and a second set of hard disks, the system comprising: a power supply module for providing a first power signal to the first set of hard disks, and starting up the first set of hard disks accordingly; and a processing module, comprising: a delay module, coupled to the power supply module, for receiving the first power signal provided by the power supply module and performing a delaying process on the first power signal to generate a delayed power signal, wherein the delay module comprises: a first resistor, having a first terminal coupled to the first power signal; a second resistor, having a first terminal coupled to a second terminal of the first resistor, and a second terminal coupled to a ground potential; a third resistor, having a first terminal coupled to the second terminal of the first resistor; and a first capacitor, having a first terminal coupled to a second terminal of the third resistor, and a second terminal coupled the ground potential; a signal adjusting module, comprising: a signal waveform adjusting module, coupled to the delay module, for receiving and adjusting the delayed power signal to form a power signal with an instantaneous amplitude change, wherein the signal waveform adjusting module comprises an inverter having an input terminal coupled to the second terminal of the third resistor, and an output terminal outputting the power signal with an instantaneous amplitude change; and a signal amplitude adjusting module, coupled to the signal waveform adjusting module, for receiving and adjusting the amplitude of the power signal outputted from the signal waveform adjusting module to generate a second power signal, wherein the signal amplitude adjusting module comprises a buffer having an input terminal coupled to the output terminal of the inverter, and an output terminal outputting the second power signal; and a switching module, coupled to the power supply module and the signal adjusting module, for receiving the first power signal and the second power signal, and determining whether or not the first power signal is provided to the second set of hard disks for starting up the second set of hard disks according to the second power signal, wherein the switching module comprises: a fourth resistor, having a first terminal coupled to the first power signal, and a second terminal coupled to the output terminal of the buffer; a transistor, having a gate coupled to the second terminal of the fourth resistor, a first terminal coupled to the first power signal, and a second terminal coupled to the second set of hard disks; and a diode, having an anode coupled to the second terminal of the transistor, and a cathode coupled to the first terminal of the transistor.