Patent ID: 7375581

Claim:
A voltage generating circuit for providing a voltage signal to a memory in a computer, the voltage generating circuit comprising: a voltage selecting circuit comprising: a first metal-oxide-semiconductor field-effect transistor (MOSFET) having a first terminal connected to a first voltage input, a second terminal, and a control terminal; a second MOSFET having a first terminal, a second terminal connected to the second terminal of the first MOSFET, and a control terminal receiving exclusively a first high level signal; and a diode having an anode connected to a second voltage input, and a cathode connected to the second terminal of the second MOSFET; and a control circuit comprising a bipolar junction transistor (BJT), the BJT having a control terminal for receiving a first voltage control signal, a first terminal connected to ground and receiving a second voltage control signal, and a second terminal connected to the control terminal of the first MOSFET and receiving a second high level signal, the control circuit responsive to the first and second voltage control signals controlling the voltage selecting circuit to gate the first voltage input or the second voltage input into the second terminal of the second MOSFET, and the first terminal of second MOSFET outputting the voltage signal to the memory.