CN102290871A - Passive low-frequency electronic paper display system - Google Patents

Abstract

The invention discloses a passive low-frequency electronic paper display system, which is characterized by comprising a wireless transmitting end, a wireless receiving end and an electronic paper display screen driving circuit, wherein the wireless transmitting end is used as master equipment to transmit wireless data to the wireless receiving end; the wireless receiving end is used as slave equipment for inducing wireless energy from a wireless transmitting coil by using an electromagnetic induction principle while receiving the wireless data to serve as electric energy of the wireless receiving end and electric energy for driving the electronic paper display screen; and in the electronic paper display screen driving circuit, the wireless energy received by the wireless receiving end is utilized as a power supply and the display content of the electronic paper display screen is updated according to the received wireless data.

Description

A kind of passive low frequency Electronic Paper display system

Technical field

The present invention relates to a kind of Electronic Paper display system, relate in particular to a kind of passive low frequency Electronic Paper display system of radio supply power mode.

Background technology

What present display device adopted mostly is that source power supply system is arranged, and promptly terminal presentation facility needs battery or external power supply that electric energy ability operate as normal, for example liquid crystal display, charactron display device etc. are provided.Need battery or external power supply that energy is provided during system works, after system's power supply was cut off, displaying contents can't keep.

Summary of the invention

The objective of the invention is to, passive low frequency Electronic Paper display system is provided.It is a kind of system that can use radio to provide electric energy as terminal electronic paper display device and control its displaying contents.

Technical scheme of the present invention: a kind of passive low frequency Electronic Paper display system is characterized in that it comprises:

Wireless transmitting terminals is launched wireless data as main equipment to the wireless interface receiving end;

The wireless interface receiving end is slave unit, in receiving radio data, utilize electromagnetic induction principle from the wireless transmission coil induction wireless energy as self electric energy and drive the electric energy of electronic-paper display screen;

The electronic-paper display screen drive circuit utilizes wireless energy that the wireless receiving termination receives as power supply, and upgrades the displaying contents of electronic-paper display screen according to the wireless data that receives.

In the aforesaid passive low frequency Electronic Paper display system, described electronic-paper display screen drive circuit comprises DC voltage booster circuit and Electronic Paper drive circuit.

In the aforesaid passive low frequency Electronic Paper display system, described DC boosting electricity is a DC-DC copped wave booster circuit.

In the aforesaid passive low frequency Electronic Paper display system, described Electronic Paper drive circuit is made up of level shifting circuit and serial/parallel transducer.

Compared with prior art, the present invention is not because the displaying contents of electronic-paper display screen needs electric energy to keep, and therefore, the display system power consumption is very low, and is energy-conservation.

Because use the wireless power technology, the wireless interface receiving end can not need to use battery or external power supply to get final product work, use, easy to maintenance.Passive low frequency Electronic Paper display system of the present invention, owing to can finish by wireless mode to the renewal of Electronic Paper displaying contents, and low frequency receives display end and utilizes wireless energy work not need battery or external power supply, and the displaying contents of Electronic Paper still can keep under the keeping that does not have electric energy.Therefore, the present invention has very high value and vast market prospect.When for example Electronic Paper being used for Commercial goods labels or electronic entrance ticket, can upgrade the displaying contents on label or the admission ticket,, have environmental protection, advantage such as convenient, fast so that recycle by wireless mode.For the terminal electronic equipment that adopts the design of this low frequency passive power supply the principle, the wireless signal that sends when transmitting terminal is enough by force the time, can make terminal electronic equipment break away from the constraint of power line or battery, just can keep the operate as normal of self by the wireless signal that receives transmitting terminal.

Description of drawings

Fig. 1 is a structured flowchart of the present invention;

Fig. 2 is a wireless power schematic diagram of the present invention;

Fig. 3 is DC voltage booster circuit figure of the present invention;

Fig. 4 is Electronic Paper drive circuit figure of the present invention.

Embodiment

The present invention is further illustrated below in conjunction with drawings and Examples, but not as the foundation to the present invention's restriction.

Embodiment.1, a kind of passive low frequency Electronic Paper display system, as shown in Figure 1, it comprises:

Wireless transmitting terminals is launched wireless data as main equipment to the wireless interface receiving end;

The wireless interface receiving end is slave unit, in receiving radio data, utilize electromagnetic induction principle from the wireless transmission coil induction wireless energy as self electric energy and drive the electric energy of electronic-paper display screen;

The electronic-paper display screen drive circuit utilizes wireless energy that the wireless receiving termination receives as power supply, and upgrades the displaying contents of electronic-paper display screen according to the wireless data that receives.

Described electronic-paper display screen drive circuit comprises DC voltage booster circuit and Electronic Paper drive circuit.Described DC boosting electricity is a DC-DC copped wave booster circuit.Described Electronic Paper drive circuit is made up of level shifting circuit and serial/parallel transducer.

Fig. 2 is a wireless power schematic diagram of the present invention.System is made up of two parts, and the left side is the wireless transmission part, and the right side is the wireless receiving part.Radiating portion is gone out data-modulated to be sent on wireless operating frequency and by Ltx inductive antenna coil with wireless signal transmission.Receiving terminal utilizes inductive antenna Ltrp and capacitor C RES to constitute resonant circuit and receives wireless signal, and receiving coil Ltrp and transmitting coil Ltx are owing to electromagnetic induction produces induced electromotive force VCL, and VCL charges to capacitor C L.Be stored in energy among the CL and be the energy source of receiving terminal work.

Itx is the electric current in the emission inductance aerial coil, and Utx is an emission inductance aerial coil both end voltage.The pass of Itx and Utx is:

$\mathrm{Itx}=\frac{1}{2\mathrm{\π}\·\mathrm{ftx}\·\mathrm{Ltx}\·(\frac{1}{\mathrm{Qant}}+1)}\·\frac{\mathrm{Utx}}{2\·2\sqrt{2}}=\frac{1}{(\mathrm{Rant}+2\mathrm{\π}\·\mathrm{ftx}\·\mathrm{Ltx})}\·\frac{\mathrm{Utx}}{2\sqrt{2}}$

$\mathrm{Rant}=\frac{2\mathrm{\π}\·\mathrm{ftx}\·\mathrm{Lant}}{\mathrm{Qant}}$

In the formula, ftx is a wireless frequency, and Ltx is the inductance value of inductance coil, and Qant is the quality factor of inductance coil, and Rant is the D.C. resistance of inductance coil.

The computing formula of the final charging voltage VCL of receiving terminal is as follows among Fig. 2:

$\mathrm{VCL}=(\mathrm{Itx}\·k\·\sqrt{\mathrm{Ltx}\·\mathrm{Ltrp}}-\mathrm{ICL}\·\sqrt{2}\·\mathrm{Ltrp})\·2\·\mathrm{\π}\·\mathrm{fres}\·\mathrm{Qtrp}\·\sqrt{2}+\frac{\mathrm{ICL}}{\mathrm{Itx}\·k\·\sqrt{2}}\·\sqrt{\frac{\mathrm{Ltrp}}{\mathrm{Ltx}}}-0.5$

Wherein, fres=ftx=wireless frequency.ICL is the direct current between the chip charge period.Qtrp is total wireless receiving and dispatching quality factor.Its computing formula is as follows:

$\mathrm{Qtrp}=\frac{2\·\mathrm{\π}\·\mathrm{fres}\·\mathrm{Ltrp}}{\mathrm{RL}}$

RF exports follow-up wireless treatment circuit to and is reduced to wireless data; Voltage output is used for the supply power voltage of wireless interface receiving end subsequent conditioning circuit.

Be electronic-paper display screen drive circuit schematic diagram.Form by two parts: DC voltage booster circuit (as shown in Figure 3) and Electronic Paper drive circuit (as shown in Figure 4).

The preceding paragraph words are revised as: the electronic-paper display screen drive circuit is made up of two parts: DC voltage booster circuit (as shown in Figure 3) and Electronic Paper drive circuit (as shown in Figure 4).

DC voltage booster circuit uses the DC-DC copped wave principle of boosting low-voltage VL is boosted to use for the Electronic Paper drive circuit as high voltage VH.If the duty ratio of PWM input signal is D, then the pass between output voltage V H and the input voltage VL is:

$\mathrm{VH}=\frac{1}{1-D}\mathrm{VL}$

The Electronic Paper drive circuit by level shifting circuit, seal in and go out change-over circuit and form.Because the number of pins of electronic-paper display screen is more, therefore use seals in and goes out change-over circuit to reduce the quantity of data input pin.Under the control of controller, video data is input to serial/parallel transducer by turn under the input clock beat, and the parallel signal of serial/parallel transducer output drives the renewal of Electronic Paper displaying contents.

Claims (4)

1. passive low frequency Electronic Paper display system is characterized in that it comprises:

Wireless transmitting terminals is launched wireless data as main equipment to the wireless interface receiving end;

The wireless interface receiving end is slave unit, in receiving radio data, utilize electromagnetic induction principle from the wireless transmission coil induction wireless energy as self electric energy and drive the electric energy of electronic-paper display screen;

The electronic-paper display screen drive circuit utilizes wireless energy that the wireless receiving termination receives as power supply, and upgrades the displaying contents of electronic-paper display screen according to the wireless data that receives.

2. passive low frequency Electronic Paper display system according to claim 1 is characterized in that: described electronic-paper display screen drive circuit comprises DC voltage booster circuit and Electronic Paper drive circuit.

3. passive low frequency Electronic Paper display system according to claim 2 is characterized in that: described DC boosting electricity is DC-DC copped wave booster circuit.

4. passive low frequency Electronic Paper display system according to claim 2 is characterized in that: described Electronic Paper drive circuit is made up of level shifting circuit and serial/parallel transducer.

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