CN101470503A

CN101470503A - CMOS chip power supply

Info

Publication number: CN101470503A
Application number: CNA2007102034587A
Authority: CN
Inventors: 魏刚
Original assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Current assignee: Hongfujin Precision Industry Shenzhen Co Ltd; Hon Hai Precision Industry Co Ltd
Priority date: 2007-12-27
Filing date: 2007-12-27
Publication date: 2009-07-01

Abstract

A CMOS chip power supply device comprises a voltage stabilizing circuit, a capacitance, a control switch and a first diode, wherein an input end of the voltage stabilizing circuit is used to connect with a system power supply of a computer, an anode of the first diode is connected with an output end of the voltage stabilizing circuit, one end of the capacitance is connected with a cathode of the first diode and a first input end of the control switch, an output end of the control switch is used to connect to a CMOS chip of the computer, and the other end of the capacitance is earthed. When the computer is started, the system power supply generates a charging voltage through the voltage stabilizing circuit and the first diode to charge the capacitance, when the computer is power off, the capacitance discharges through the control switch to supply power for the CMOS chip. The CMOS chip power supply device has simple structure and relatively low cost.

Description

The CMOS chip power supply

Technical field

The present invention relates to a kind of electric supply installation, particularly a kind of electric supply installation of CMOS chip.

Background technology

As everyone knows, CMOS chip in the computer is the read-write RAM chip of on the computer main board, be mainly used to preserve the hardware configuration of current system and operating personnel setting to some parameter, the CMOS chip is powered by system power supply when start, then pass through a backup battery during shutdown by system, it is the CMOS powered battery, therefore no matter be at off-mode, still under the situation of system's power down, CMOS information can not lost, the total voltage of CMOS battery is 3V, and cannot charge in circuit, so the voltage of CMOS battery can constantly reduce in time, when its voltage consumption to deficiency thinks that CMOS information is preserved circuit supply, the information errors of some parameter can appear in computer, or travelling speed waits a series of problem slowly, usually, CMOS battery service time is one to two year, far below the serviceable life of computer, therefore need often to change the CMOS battery, preserved with the configuration information that guarantees computer.

Summary of the invention

In view of above content, be necessary to provide a kind of CMOS chip power supply, the power-on time that can prolong the CMOS battery.

A kind of CMOS chip power supply, comprise a mu balanced circuit, one electric capacity, one gauge tap and one first diode, the input end of described mu balanced circuit is used to connect a system power supply of a computer, the anode of described first diode connects the output terminal of described mu balanced circuit, one end of described electric capacity connects the negative electrode of described first diode, and connect a first input end of described gauge tap, the output terminal of described gauge tap is used to connect the CMOS chip of described computer, the other end ground connection of described electric capacity, during booting computer, described system power supply is through described mu balanced circuit and described first diode, produce a charging voltage, be described electric capacity charging, during shut down of computer, described electric capacity discharges by described gauge tap, is described CMOS chip power supply.

It is described electric capacity charging when booting computer that described CMOS chip power supply utilizes the system power supply of computer, the energy of capacitance stores can be by described gauge tap during shut down of computer, be the CMOS chip power supply, slowed down the consumption of CMOS cell voltage, prolonged the life-span of CMOS battery, and described CMOS chip power supply has used less elements, and simple in structure, cost is lower.

Description of drawings

Below in conjunction with accompanying drawing and better embodiment the present invention is described in further detail:

Fig. 1 is the circuit diagram of CMOS chip power supply better embodiment of the present invention.

Embodiment

Please refer to Fig. 1, CMOS chip power supply of the present invention comprises a mu balanced circuit 10, feed circuit 20, a diode D1 and a gauge tap 30.

Described mu balanced circuit 10 comprises that a model is adjustable shunting reference source T, two divider resistance R1, R2 and the current-limiting resistance R3 of TL431, the end that described divider resistance R1, R2 link to each other connects the reference edge of described adjustable shunting reference source T, the other end of divider resistance R1, R2 connects negative electrode, the anode of described adjustable shunting reference source T respectively, the negative electrode of described adjustable shunting reference source T is connected to a 5V system power supply by described current-limiting resistance R3, and link to each other the plus earth of described adjustable shunting reference source T with the anode of described diode D1.

Described feed circuit 20 comprise current-limiting resistance R4, R5 and a farad capacitor (large bulk capacitance) C1, and the end that described current-limiting resistance R4, R5 link to each other connects the negative electrode of described diode D1, and the other end of described current-limiting resistance R4 is by described farad capacitor C1 ground connection.

Described gauge tap 30 comprises two diode D2, the D3 that negative electrode links to each other, the anode of diode D2 connects the other end of described current-limiting resistance R5, the anode of described diode D3 connects the positive pole of a CMOS battery J by a current-limiting resistance R6, the minus earth of described CMOS battery J, the connected node of described diode D2, D3 is used to connect a CMOS chip 40, and by a filter capacitor C2 ground connection.

When booting computer, because of the load current of CMOS chip 40 very little, so the pressure drop of current-limiting resistance R5 is also very little, described 5V system power supply is by diode D1, current-limiting resistance R5, produce voltage at the anode of described diode D2 greater than CMOS battery J voltage, make described diode D2 conducting, and diode D3 ends, be that described 5V system power supply is by diode D1, current-limiting resistance R5 and diode D2 are described CMOS chip power supply, described 5V system power supply is described adjustable shunting reference source T power supply simultaneously, by described divider resistance R1 is set, the resistance of R2 makes the negative electrode of described adjustable shunting reference source T export a stable voltage, as 4V, through described diode D1 and current-limiting resistance R4, produce the voltage greater than CMOS battery J voltage,, be described farad capacitor C1 charging as 3.3V.

Behind the shut down of computer, described 5V system power supply stops described CMOS chip 40 power supplies, described farad capacitor C1 is by current-limiting resistance R4, the R5 discharge, diode D2 conducting, diode D3 ends, described farad capacitor C1 is described CMOS chip 40 power supplies, and described CMOS battery J is not to 40 power supplies of CMOS chip, described farad capacitor C1 is after discharge a period of time, when its voltage during less than the current voltage of described CMOS battery J, diode D2 ends, diode D3 conducting, described CMOS battery J just is described CMOS chip 40 power supplies, in the present embodiment, the model of described diode D1 is IN4148, can prevent that described farad capacitor C1 from discharging to described mu balanced circuit 10 when shut down of computer.

Because of CMOS chip 40 power consumptions pressure is very little,, slowed down the consumption of CMOS battery J electric energy again, prolonged the life-span of CMOS battery J so just can keep a couple of days described CMOS chip 40 by described farad capacitor C1 electric energy stored.

Claims

[claim 1] a kind of CMOS chip power supply, comprise a mu balanced circuit, one electric capacity, one gauge tap and one first diode, the input end of described mu balanced circuit is used to connect a system power supply of a computer, the anode of described first diode connects the output terminal of described mu balanced circuit, one end of described electric capacity connects the negative electrode of described first diode, and connect a first input end of described gauge tap, the output terminal of described gauge tap is used to connect the CMOS chip of described computer, the other end ground connection of described electric capacity, during booting computer, described system power supply is through described mu balanced circuit and described first diode, produce a charging voltage, be described electric capacity charging, during shut down of computer, described electric capacity discharges by described gauge tap, is described CMOS chip power supply.
[claim 2] CMOS chip power supply as claimed in claim 1, it is characterized in that: described mu balanced circuit comprises an adjustable shunting reference source, one first divider resistance, one second divider resistance and one first current-limiting resistance, the negative electrode of described adjustable shunting reference source connects the anode of described first diode, and connect described system power supply by described first current-limiting resistance, the plus earth of described adjustable shunting reference source, its reference edge connects described first, one end of second divider resistance, described first, the other end of second divider resistance connects the negative electrode of described adjustable shunting reference source respectively, anode.
[claim 3] CMOS chip power supply as claimed in claim 1, it is characterized in that: described gauge tap comprises one second diode and one the 3rd diode, described second, the negative electrode of the 3rd diode links to each other, the anode of its connected node and described second diode is respectively as the output terminal and the first input end of described gauge tap, the anode of described the 3rd diode is as one second input end of described gauge tap, be used to connect the positive pole of a CMOS battery, the minus earth of described CMOS battery, when described charging voltage during greater than the current voltage of described CMOS battery, described charging voltage is described CMOS chip power supply, when described charging voltage during less than the current voltage of CMOS battery, described CMOS battery is described CMOS chip power supply by described gauge tap.
[claim 4] CMOS chip power supply as claimed in claim 3, it is characterized in that: also be connected one second current-limiting resistance between described first diode and the described electric capacity, also be connected one the 3rd current-limiting resistance between described second current-limiting resistance and the gauge tap, also be connected one the 4th current-limiting resistance between described gauge tap and the described CMOS battery.
[claim 5] CMOS chip power supply as claimed in claim 4 is characterized in that: described electric capacity is a jumbo electric capacity.