CN115333578B

CN115333578B - Electronic device and method for operating the electronic device

Info

Publication number: CN115333578B
Application number: CN202210505174.8A
Authority: CN
Inventors: N·科迪尔; 甄家灏; K·布拉哈
Original assignee: Stmicroelectronics Development Co ltd; STMicroelectronics SA; STMicroelectronics Rousset SAS
Current assignee: Stmicroelectronics Development Co ltd; STMicroelectronics SA; STMicroelectronics Rousset SAS
Priority date: 2021-05-11
Filing date: 2022-05-10
Publication date: 2025-04-04
Anticipated expiration: 2042-05-10
Also published as: CN115333578A

Abstract

Embodiments of the present disclosure relate to radio frequency identification, qi, wireless power devices. An apparatus is provided that includes a frequency demodulator and an amplitude demodulator. The device is configured to use the frequency demodulator and the amplitude demodulator in parallel in a first mode and to activate a Radio Frequency Identification (RFID) card mode or a Qi charger mode based on a result provided by the demodulator.

Description

Electronic device and method for operating the same

Technical Field

The present disclosure relates generally to electronic devices, and more particularly, to electronic devices that integrate RFID (radio frequency identification) technology.

Background

Contactless technology is very widespread and is widely used in transportation and access control applications. The current trend is to group functions (traditionally carried by contactless cards or IC cards) as much as possible onto a single device, such as a mobile phone.

Disclosure of Invention

There is a need for improved contactless access devices, in particular those equipped with RFID technology.

One embodiment provides an apparatus comprising a frequency demodulator and an amplitude demodulator, the apparatus being configured to use two demodulators in parallel in a first mode and to activate an RFID card mode or a Qi charger mode based on the result provided by the demodulators.

One embodiment provides a method implemented by an apparatus comprising a frequency demodulator and an amplitude demodulator, wherein the apparatus uses two demodulators in parallel in a first mode and uses two demodulators in succession in a second mode.

According to an embodiment, both the frequency demodulator and the amplitude demodulator further comprise a load modulator/demodulator.

According to one embodiment, in the second mode, both the frequency demodulator and the amplitude demodulator are continuously operated.

According to one embodiment, the load modulator of the apparatus is used when the apparatus communicates with an external RFID-type device configured in reader mode.

According to one embodiment, the load modulator is used when the device is charged by an external apparatus, and when the device emulates an RFID card configured as type a.

According to an embodiment, when the apparatus is in the second mode, the Qi analog front end of the apparatus is adapted for frequency or amplitude modulated data, the frequency modulated data being used for communication with the Qi charger device, the amplitude modulated data being used for communication with the RFID device configured in the card mode.

According to one embodiment, an amplitude demodulator is used to demodulate the response of an external type a device configured in card mode in load modulation.

According to an embodiment, the amplitude demodulator is for demodulating a command received from an external device configured in a reader mode.

According to an embodiment, the frequency demodulator is for demodulating a response received from an external B-mode device configured in a card mode.

According to an embodiment, the frequency demodulator is used to demodulate a digital ping or any subsequent data packet received from an external charging device.

According to an embodiment, the frequency demodulator is for demodulating a response received from the external chargeable device.

According to one embodiment, when an external field is detected on the antenna, it is checked whether the field is from the RFID device or from the Qi device.

According to an embodiment, the check is performed by transmitting periodic interrogation frames in RFID mode and Qi mode.

Drawings

The above features and advantages and other will be described in detail in the following description of particular embodiments, given by way of illustration, and not limitation, with reference to the accompanying drawings, in which:

fig. 1 schematically shows an example of a communication system comprising a device of Qi technology, to which the described embodiments are applied as an example;

FIG. 2 shows a timing diagram of the mode of operation of the device of FIG. 1;

FIG. 3 shows a flow chart illustrating a portion of the timing diagram shown in FIG. 2;

FIG. 4 illustrates a portion of an example of the timing diagram shown in FIG. 2;

FIG. 5 illustrates a block diagram of an embodiment of a communication circuit of the apparatus of FIG. 1;

FIG. 6 illustrates a first example of operation of the circuit shown in FIG. 5;

FIG. 7 illustrates another example of a portion of the timing diagram shown in FIG. 2;

FIG. 8 illustrates a second example of operation of the circuit shown in FIG. 5;

FIG. 9 illustrates another example of a portion of the timing diagram shown in FIG. 2;

FIG. 10 illustrates a third example of operation of the circuit shown in FIG. 5;

FIG. 11 illustrates a fourth example of operation of the circuit shown in FIG. 5;

FIG. 12 illustrates a fifth example of operation of the circuit shown in FIG. 5;

FIG. 13 shows a sixth example of operation of the circuit of FIG. 5, and

Fig. 14 shows another partial example of the timing chart shown in fig. 2.

Detailed Description

Like features have been designated by like reference numerals throughout the various figures. In particular, structural and/or functional features common in the various embodiments may have the same reference numerals and may have the same structural, dimensional, and material characteristics.

For clarity, only the operations and elements that are helpful in understanding the embodiments described herein have been illustrated and described in detail. Specifically, the circuits determined according to their respective functions are not described in detail in terms of structure.

Unless otherwise indicated, when referring to two elements being connected together, this means a direct connection without any intervening elements other than a conductor, and when referring to two elements being coupled together, this means that the two elements may be connected, or may be coupled, by one or more other elements.

In the following disclosure, unless otherwise indicated, when absolute positional qualifiers, such as the terms "front", "rear", "upper", "lower", "left", "right", etc., or relative positional qualifiers, such as the terms "upper", "lower", "high", "low", etc., or orientation qualifiers, such as "horizontal", "vertical", etc., are referred to in the directions shown in the drawings.

Unless otherwise specified, expressions of "about", "approximately", "substantially" and "in the order of magnitude" mean within 10%, preferably within 5%.

In the present specification, it is suggested to take advantage of the fact that Qi technology (corresponding to the standard developed by the wireless power alliance for wireless energy transfer) is widely developed in new smart phones. The Qi technique is particularly interesting because it is applicable to frequency bands including Low Frequencies (LF) (100 kHz to 200 kHz). Thus, in this specification, it is sought to establish LF communication by RFID technology by using some components of the circuit dedicated to Qi technology.

Fig. 1 schematically shows an example of a communication system comprising a device of Qi technology, to which the disclosed embodiments are applicable as an example.

The system 11 shown in fig. 1 comprises an electronic device 13, which electronic device 13 is adapted to communicate with other electronic devices/means using Qi technology and RFID technology.

According to one embodiment, the device 13 is a mobile phone, such as a smart phone or tablet computer.

According to the embodiment shown in fig. 1, the device 13 is adapted to be charged by a Qi charger platform 15 (chargeable mode) or to charge another electronic device 17 equipped with Qi technology (charger mode). In other words, the device 13 is adapted to be adjusted according to its external environment to switch from the charger mode to the chargeable mode. The device 13 may then operate in a charger mode and charge the devices in its environment, or in a chargeable mode and be charged by the charger devices in its environment.

According to the embodiment shown in fig. 1, the device 13 is further adapted to communicate with an RFID device configured in the card mode 19 and an RFID device configured in the reader mode 21. In other words, the device 13 is adapted to adjust from the reader mode to the card mode depending on its external environment. The device 13 may then operate in a reader mode and communicate with devices in a card mode that are present in its environment, or in a card mode and communicate with devices in a reader mode that are present in its environment.

According to one example of application, the embodiments are applicable to transportation systems and access control, for example, to doors of buildings equipped with Low Frequency (LF) technology.

Fig. 2 is a timing diagram illustrating the mode of operation of the device of fig. 1.

When the device 13 shown in fig. 1 is not communicating, it is in a low power mode or standby state to reduce power consumption.

When the device 13 is in a standby state, it should still be able to detect the presence of an RFID reader, an RFID card, a chargeable device or a charger device.

The timing diagram shown in fig. 2 includes two consecutive parts I and II, part I corresponding to the operation when the device 13 is in the standby mode and part II corresponding to the operation when the device 13 is in the normal mode called the polling mode.

According to the embodiment shown in fig. 2, when the device 13 is in standby mode (part I), it "detects" its environment by transmitting pulses 23 for a short period. For example, two pulses 23 are separated by a time interval 25. Pulse 23 corresponds to a short field emission of device 13 to detect a possible device configured in card mode or a chargeable device present in the field of device 13. In case such a device is detected, the device 13 then wakes up from the standby state and switches to the normal mode (part II). This detection enables an analysis of the amount of power (e.g. amplitude or phase) specific to these pulses 23, which can change if a device or a chargeable device configured in card mode is nearby.

During interval 25, device 13 is in listener mode for a device or range of charger devices that are in reader mode.

Fig. 3 is a flow chart illustrating a portion of the timing diagram of fig. 2. More precisely, the flow chart corresponds to an implementation example of the listener mode.

If the device 13 detects a field (block 61, a field is detected), the device activates by exiting the standby mode (block 63, entering the active mode) and responding to the reader or charger device according to the detected technology.

More precisely, the device 13 comprises two demodulators, one demodulator being adapted to demodulate an on-off keying (OOK) modulation and the other demodulator being adapted to demodulate a Frequency Shift Keying (FSK) modulation. When both demodulators are enabled, the device 13 is in normal mode (block 65, OOK and FSK demodulators are enabled).

In response to the reader or charger device, the device 13 detects the device technology within range and more accurately detects the modulation type on which it is based. Thus, the device 13 detects an on-off keying (OOK) modulation (block 67, OOK detected) or a Frequency Shift Keying (FSK) modulation (block 73, FSK detected).

The response of the device 13 is adapted to the detected device modulation type.

If, in addition to OOK modulation, type a is detected based on the start of the frame, the device 13 responds by sending a reply with load modulation according to the RFID standard (block 69, type a detected based on the start of the frame: sending a reply with load modulation according to the RFID standard).

If, in addition to OOK modulation, type B is detected based on the start of the frame, the device 13 also turns on the field after the off-detection of the field and responds by modulating the reply according to the RFID standard using FSK (block 71, on the field after the off-detection of the field based on type B detected by the start of the frame and replying according to the RFID standard using FSK).

If FSK modulation is detected, the device 13 responds by using the load modulation according to the Qi standard (block 75, qi charger: responds with the load modulation according to the Qi standard).

According to the embodiment shown in fig. 2, in the normal mode (part II) the device 13 emits periodic interrogation frames 27 during which the device 13 generates a field for card mode devices or chargeable devices within range. The inquiry frame 27 may be repeated several times for any card mode device reply before returning to standby mode. The purpose of these periodic frames (polling cycles) is to determine the type of external device based on the type of transmitted frame to which the external device is responding.

Frame 27 is for example made up of two consecutive transmit bursts 29 and 31, burst 29 (LF RFID request) being configured to generate a field understandable by the card mode device and burst 31 (reverse Qi) being configured to generate a field understandable by the chargeable device.

In other words, during frame 27, device 13 consecutively implements two transmit bursts 29 and 31, each transmit burst 29 and 31 representing a type of technology (Qi or RFID). The types of technology targeted by the burst are in turn RFID technology and Qi technology.

Fig. 4 shows an expanded example of the timing diagram portion shown in fig. 2. More precisely, fig. 4 shows a timing diagram of frame 27.

According to the embodiment shown in fig. 4, burst 29 comprises a Guard time followed by two consecutive requests, each request representing type a or type B. Each of the first request (OOK type a command) and the second request (OOK type B command) is followed by a wait time 33 (timeout for receiving a response). During the waiting time 33, the device 13 waits for a response of the type a card mode device or the type B card mode device in its field.

According to the embodiment shown in fig. 4, burst 29 and burst 31 are separated by a reset time (reset).

According to the embodiment shown in fig. 4, burst 31 comprises a guard time (guard time), followed by a request (digital ping) representing Qi technology. The request is followed by a waiting time 33 (timeout of the received response). During the waiting time 33, the device 13 waits for a response of the device charging in its field.

According to the embodiment shown in fig. 4, device 13 is in listener mode before burst 29, between bursts 29 and 31, and after burst 31.

According to one embodiment, the duration of each pulse 23 is between 50 microseconds (μs) and 100 μs, for example on the order of 70 μs, and the duration of each pulse 29, 31 is between 50 milliseconds (ms) and 100ms, for example on the order of 70 ms. The duration of the interval 25 and the waiting time 33 is between 200ms and 1 s.

Fig. 5 schematically shows an embodiment of the communication circuit 35 of the device 13 shown in fig. 1 in block form.

The communication circuit 35 is coupled to an antenna 37 (antenna) via a matching circuit 39 (matching circuit). The communication circuit 35 may also be coupled to an application processor 41 (AP) and/or a secure element 43 (SE).

According to the embodiment shown in fig. 3, the communication circuit 35 comprises:

A controller 45 (controller), for example a microcontroller or microprocessor for managing the exchanges between the different elements of the circuit 35;

An RFID reader wireless encoder/decoder 47 (RFID-RW-UART) coupled to the controller 45 for encoding/decoding data in a reader mode;

an RFID card analog receiver/transmitter 49 (RFID-CE-UART) coupled to the controller 45 for encoding/decoding data in card mode;

A Qi receiver/transmitter analog front end 51 (Qi receiver/transmitter analog front end) coupled to the matching circuit 39 for shaping the received and to be transmitted signals;

a transmission/transmission circuit 53 (TX driver) for amplifying the signal supplied from the controller 45 to the Qi analog front end 51 in transmission;

A frequency demodulator and a load modulator/modem (also called backscatter) 55 (Qi demodulator LM/FSK) located between Qi analog front end 51 and controller 45 for frequency demodulating the signal received by Qi analog front end 51;

A load modulator 57 (load modulator) located between the controller 45 and the matching circuit 39 for affecting the external magnetic field in the RFID card mode or the charger mode, and

An amplitude demodulator and load modulator/demodulator 59 (RFID demodulator OOK/LM), located between the matching circuit 39 and the controller 45, is adapted to demodulate the received signals in RFID card and reader modes, respectively.

According to an embodiment, the controller 45 comprises an encoding circuit dedicated to Qi technology.

Fig. 6 to 14 show six examples of the operation of the circuit 35, depending on the external device it detects or the external device it detects. In each of fig. 6 to 14, components not requested in the illustrated use example are not shown.

Fig. 6 shows the circuit 35 when the device 13 detects in reader mode and communicates with an LF device of type a configured in card mode.

Fig. 7 shows a timing diagram of an example of frame 27 in circuit 35 of fig. 6.

According to the embodiment shown in fig. 6 and 7, the device 13 operates in reader mode when the device 13 detects an external class a device configured in card mode and communicating at Low Frequency (LF).

In this mode, the application processor runs (link a) I) a low frequency RFID reader wireless application using the controller 45.

The controller 45 uses the RFID reader wireless encoder/decoder 47 to construct a low frequency RFID reader wireless command or LF RFID RW command (link a) II.

The controller 45 uses the TX driver 53 and Qi analog front end 51 to generate LF RFID RW commands according to type a using on-off keying modulation (OOK type a commands a) III, fig. 7) (link a) III).

The response from the card-mode external device to device 13 (LM tag response, fig. 7) is demodulated using load demodulation via RFID demodulator 59 (link a IV).

According to an embodiment not shown, the response of the external device in card mode to the device 13 is demodulated by the Qi demodulator 55.

The controller 45 then decodes the external device in a card mode response (link a) V using the RFID reader wireless encoder/decoder 47 and forwards the corresponding data to the application processor 41 (link a) VI).

During this operation, the controller 45 may use the secure element 43 to perform any desired cryptographic operations.

After contact is established between the device 13 and the devices within range, both communicate by sending successive commands and responses.

Fig. 8 shows the circuit 35 when the device 13 detects and communicates with a type B LF device configured in card mode in reader mode.

Fig. 9 is a timing diagram of an example of frame 27 in circuit 35 of fig. 8.

According to the embodiment shown in fig. 8, the detection of an external B-type device configured in card mode is performed after no response to a request in type a.

According to the embodiment shown in fig. 8, when the device 13 detects an external type B device configured in card mode and communicating in LF, the device 13 operates in reader mode.

In this mode, the application processor runs (link b) I) a low frequency RFID reader wireless application using the controller 45.

The controller 45 uses the RFID reader wireless encoder/decoder 47 to construct a low frequency RFID reader wireless command or LF RFID RW command (link b) II).

The controller 45 generates the LF RFID RW command according to type B by using on-off keying amplitude modulation (OOK type B command B) III, fig. 9) (link B) III) using the TX driver 53 and Qi analog front end 51.

After generating the command, the device 13 stops its magnetic field and waits for a reply from the external device.

The response from the card-mode external device to device 13 (FSK type B response, fig. 9) is demodulated via Qi demodulator 55 (link B) IV using frequency shift keying demodulation (FSK demodulation).

The controller 45 then decodes the external device in a card mode response (link b) V using the RFID reader wireless encoder/decoder 47 and forwards the corresponding data to the application processor 41 (link b) VI).

After contact is established between the device 13 and devices within range, they all communicate by sending successive commands and responses.

Fig. 10 shows the circuit 35 when the device 13 detects and communicates with a low frequency device of type a configured in the reader mode in the card mode.

According to the embodiment shown in fig. 10, when the device 13 detects an external class a device configured in the reader mode and communicating in the LF, the device 13 operates in the card mode.

In this mode, the application processor runs (link c) the I low frequency RFID card emulation application using the controller 45.

Commands from the external device in reader mode to device 13 are demodulated using on-off keying amplitude demodulation via RFID demodulator 59 (link c) II.

Then, the controller 45 decodes the external device command (link c) III using the RFID card analog encoder/decoder 49, and constructs the response (link c) IV) using the RFID card analog encoder/decoder 49.

The controller 45 uses the load modulation (link c) V) and, with the device in card mode, uses the load modulator 57 to generate a response according to type a via the matching circuit 39.

Fig. 11 shows the circuit 35 when the device 13 detects and communicates with a type B LF device configured in reader mode in card mode.

According to the embodiment shown in fig. 11, when the device 13 detects an external type B device configured in reader mode and communicating in LF, the device 13 operates in card mode.

In this mode, the application processor runs (link d) I) the low frequency RFID card emulation application using the controller 45.

Commands from the external device in reader mode to device 13 are demodulated using on-off key demodulation via RFID demodulator 59 (link d) II).

Then, the controller 45 decodes the external device command (link d) III using the RFID card analog encoder/decoder 49, and constructs the response (link d) IV) using the RFID card analog encoder/decoder 49.

The controller 45 uses frequency shift keying modulation (FSK modulation) (link d) V) and uses the TX driver 53 and Qi analog front end 51 to generate a response according to type B via the matching circuit 39 with the device in card mode.

During this operation, the controller 45 may perform any cryptographic operations required using the secure element 43.

Fig. 12 shows the circuit 35 when the device 13 detects a charger device and is charged by it.

According to the embodiment shown in fig. 12, when the device 13 detects an external charger Qi device, the device 13 operates in a charging mode.

In this mode, qi analog ping from the external device in charger mode to device 13 is demodulated using FSK demodulation via Qi demodulator 55 and decoded by controller 45 (link e) I).

The controller 45 generates a response via the matching circuit 39 (link e) II) using the load modulator 57.

The device 13 is then charging and the controller 45 transmits the monitoring data to the application processor 41 (link e) III.

During this operation, the controller 45 may use the secure element 43 if authentication needs to be performed.

Fig. 13 shows the circuit 35 when the device 13 detects and charges a chargeable device.

Fig. 14 is a timing diagram of an example of frame 27 in circuit 35 of fig. 13.

According to the embodiment shown in fig. 13 and 14, the detection of the chargeable device is performed after no response to the RFID request (frame 27).

According to the embodiment shown in fig. 13, when the device 13 detects an external Qi device in the charger mode, the device 13 operates in the charger mode.

In this mode, the controller 45 uses the TX driver 53 and Qi analog front end 51 to send digital Qi ping (digital ping f) I using FSK modulation (link f) I, fig. 14.

The response from the external device (LM reply from the device to be charged, fig. 14) is demodulated by QiQi analog front end 51 (link f) II) using Qi demodulator 55 and decoded by controller (link f) III.

The device 13 then charges the devices within range and the controller 45 transmits the monitoring data to the application processor 41 (link f) III.

After contact is established between the device 13 and devices within range, they all communicate by sending successive commands and responses. Any subsequent data packets received from the external charger device may then be demodulated by Qi demodulator 55.

According to the disclosed embodiment, during phase I shown in fig. 2, the device 13 is adapted to use the Qi demodulator and the RFID demodulator in parallel, while during phase II, the device 13 is adapted to use the Qi demodulator and the RFID demodulator in sequence.

An advantage of the embodiments is that they make it possible to combine the RFID LF and Qi technologies within the same circuit.

Various embodiments and variations have been described. Those skilled in the art will appreciate that certain features of the embodiments can be combined and that other variations will readily occur to those skilled in the art.

Finally, based on the functional description provided above, the actual implementation of the embodiments and variants described herein is within the ability of those skilled in the art.

A device may be summarized as comprising a frequency demodulator (55) and an amplitude demodulator (59), the device being configured to use two demodulators in parallel in a first mode (I) and to activate an RFID card mode or a Qi charger mode based on a result provided by the demodulators.

The method implemented by the device may be summarized as comprising a frequency demodulator (55) and an amplitude demodulator (59), wherein the device uses two demodulators in parallel in a first mode (I) and two demodulators in series in a second mode (II).

The frequency and amplitude demodulator may also include a load modulator/demodulator.

In the second mode, both the frequency demodulator and the amplitude demodulator may operate continuously.

The load modulator (57) of the device may be used when the device communicates with an external RFID device configured in reader mode.

The load modulator (57) may be used when the device is charged by an external device and when it emulates an RFID card in a type a configuration.

When the device is in the second mode, the Qi analog front end (51) of the device may be adapted for frequency or amplitude modulated data, the frequency modulated data being used for communication with the Qi charger device, the amplitude modulated data being used for communication with the RFID device configured in the card mode.

An amplitude demodulator (59) may be used to demodulate the response of an external type a device configured in card mode in load modulation.

An amplitude demodulator (59) may be used to demodulate commands received from an external device configured in reader mode.

A frequency demodulator (55) may be used to demodulate responses received from external B-mode devices configured in card mode.

The frequency demodulator (55) may be used to demodulate digital pings or any subsequent data packets received from an external charging device.

A frequency demodulator (55) may be used to demodulate responses received from the external chargeable device.

When a device detects an external field on the antenna, it can be checked whether the external field is from an RFID device or from the Qi device.

The check may be performed by transmitting periodic interrogation frames in RFID mode and Qi mode.

The various embodiments described above may be combined to provide further embodiments. These and other changes can be made to the embodiments in light of the above-detailed description. In general, in the following claims, the terms used should not be construed to limit the claims to the specific embodiments disclosed in the specification and the claims, but should be construed to include all possible embodiments and all equivalents to which such claims are entitled. Accordingly, the claims are not limited by the present disclosure.

Claims

1. An electronic device, comprising:

a frequency demodulator configured to provide a first demodulation result, and

An amplitude demodulator configured to provide a second demodulation result, wherein:

The electronic device is configured to:

In a first mode, the frequency demodulator and the amplitude demodulator are used in parallel, and

Activating a radio frequency identification RFID card mode or a Qi charger mode based on the first demodulation result and the second demodulation result, and

The frequency demodulator and the amplitude demodulator are continuously used in a second mode.

2. The electronic device of claim 1, further comprising a load modulator configured to influence an external magnetic field in the RFID card mode or the Qi charger mode.

3. The electronic device of claim 2, wherein the electronic device uses the load modulator in response to the electronic device communicating with an external RFID type a apparatus configured in a reader mode.

4. The electronic device of claim 3, wherein the load modulator is used in response to the electronic device being charged by an external apparatus or when the electronic device emulates an RFID card configured as type a.

5. The electronic device of claim 1, comprising:

The Qi analog front end is configured to frequency modulate data or amplitude modulate data responsive to the electronic device being in the second mode, the frequency modulated data for communication with the Qi chargeable device, and the amplitude modulated data for communication with the RFID device configured in the card mode.

6. The electronic apparatus of claim 1, wherein the amplitude demodulator is configured to demodulate a response of an external RFID type a device configured in a card mode.

7. The electronic device of claim 1, wherein the amplitude demodulator is configured to demodulate commands received from an external apparatus configured in a reader mode.

8. The electronic apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a response received from an external B-mode device configured in a card mode.

9. The electronic apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a digital ping or subsequent data packet received from an external charging device.

10. The electronic apparatus of claim 1, wherein the frequency demodulator is configured to demodulate a response received from an external chargeable device.

11. The electronic device of claim 1, comprising:

an antenna, wherein in response to detecting an external field on the antenna, the electronics checks whether the field is generated by an RFID device or by a Qi device.

12. The electronic device of claim 11, wherein the electronic device checks whether the field is generated by the RFID apparatus depending on whether a modulation type is amplitude modulated or frequency modulated.

13. A method for operating an electronic device, comprising:

Providing a first demodulation result by a frequency demodulator of the apparatus;

providing a second demodulation result by an amplitude demodulator of the device;

in a first mode, the frequency demodulator and the amplitude demodulator are used in parallel;

In the second mode, the frequency demodulator and the amplitude demodulator are continuously used.

14. The method of claim 13, wherein the apparatus further comprises a load modulator configured to influence an external magnetic field in the RFID card mode or the Qi charger mode.

15. The method of claim 14, comprising:

The load modulator is used in response to communicating with an external RFID type a device configured in a reader mode.

16. The method of claim 15, comprising:

The load modulator is used in response to the device being charged by an external device or in response to the device emulating an RFID card configured as type a.

17. The method of claim 13, comprising:

In response to the device being in the second mode, frequency modulated data or amplitude modulated data, the frequency modulated data being for communication with a Qi chargeable device, the amplitude modulated data being for communication with an RFID device configured in a card mode.

18. The method of claim 13, wherein the amplitude demodulator is configured to demodulate a response of an external RFID type a device configured in a card mode.

19. The method of claim 13, wherein the amplitude demodulator is configured to demodulate commands received from an external device configured in a reader mode.

20. The method of claim 13, wherein the frequency demodulator is configured to demodulate a response received from an external B-mode device configured in a card mode.

21. The method of claim 13, wherein the frequency demodulator is configured to demodulate a digital ping or subsequent data packet received from an external charging device.

22. The method of claim 13, wherein the frequency demodulator is configured to demodulate a response received from an external chargeable device.

23. The method of claim 13, comprising:

In response to detecting an external field on the antenna, it is checked whether the field is generated by the RFID device or by the Qi device.

24. The method of claim 23, comprising:

A periodic interrogation frame is transmitted to detect whether the Qi device or the RFID device, which is chargeable, is within range.

25. The method of claim 13, comprising:

When operating in the low power mode, the RFID device or Qi device is detected,

In response to detecting the RFID device or the Qi device, transitioning to a polling mode, and

In the polling mode, it is determined whether the RFID device or the Qi device is within range.