Power supply unit and computer
View Patent ↗A series power supply circuit and a switching power supply circuit are combined within a single power supply unit. The switching power supply circuit provides an efficiency lower than that of the series power supply circuit under a light load and provides an efficiency higher than that of the series power supply circuit under a heavy load. A standby signal that is asserted under a light load and is deasserted under a heavy load is input to a negative logic enable terminal (−EN) of the series power supply circuit through an inverter 0 . The standbysignal is directly input to the negative logic enable terminal (−EN) of a PWM controller in the switching power supply circuit.
1. A voltage converter comprising:
a first power supply circuit capable of converting an input voltage to an output voltage;
a second power supply circuit capable of converting said input voltage to said output voltage, wherein said second power supply circuit is connected in parallel with said first power supply circuit; and
a detecting circuit for activating either said first power supply circuit to said second power supply circuit to convert said input voltage to said output voltage based on an amount of current supplied to said first and second power supply circuits.
2. The voltage converter of claim 1 , wherein said first power supply circuit is a series power supply circuit, and said second power supply circuit is a switching power supply circuit.
3. The voltage converter of claim 1 , wherein said first power supply circuit has a relatively high conversion efficiency during a low load demand, and said second power supply circuit has a relatively high conversion efficiency during a high load demand.
4. The voltage converter of claim 1 , wherein said first power supply is activated by said detecting circuit when said current amount is below a predetermined value, wherein said second power supply is activated by said detecting circuit when said current amount exceeds said predetermined value.
5. The voltage converter of claim 1 , wherein said current amount is below a predetermined value when said voltage converter is in a suspended state, wherein said current amount exceeds said predetermined value when said voltage converter is in a non-suspended state.
6. The voltage converter of claim 1 , wherein said first and second power supply circuits share a common voltage input and a common voltage output.
7. The voltage converter of claim 1 , wherein said detecting circuit includes a current sense amplifier coupled to a power input line for said first and second power supply circuits.