FR2878376A1 - Connector e.g. universal serial bus mini B type connector, for e.g. wireless telephone, has switch to permit multiplexing of audio signals with signals driven on serial bus cables and on data download/transfer cable, issued from pins - Google Patents

Abstract

The connector has a set of contact pins comprising contact pins (5-8) connected to a STG3699switch (22). The switch enables each one of the contact pins of the set to be interconnected to two distinct internal signals of a communication terminal, to permit multiplexing of audio signals with the signals driven on universal serial bus (USB) cables and on data download/transfer cable, issued from the pins (5-8). Independent claims are also included for the following: (A) a communication terminal comprising an electronic circuit having a connector (B) a cable comprising a connection unit to connect a connector.

Description

Single connector for radiotelephone, electronic circuit,

  corresponding radiotelephone and cable.

  FIELD OF THE INVENTION The field of the invention is that of radiotelephones, and in particular of the connectors implemented in a radiotelephone.

  More specifically, the invention relates to the optimization of multiple connectors for accessing different devices, for example implementing functions of the type: - data download RS232 link; - data transfer on RS232 link; -transfer of data over USB link; - charge of a battery; -transmission of incoming and / or outgoing audio signals; serial transmission type I2C; in a radiotelephone.

  2. Prior art According to the known techniques, a connector is provided for each of the functions that can be envisaged in a radiotelephone. Thus, a radiotelephone comprises a plurality of connectors, making it possible to access the various peripherals: a connector for the USB links, a connector for the serial links for data transfer and download, a connector for the audio inputs / outputs, etc. .

  This poses problems of space (the radiotelephones being increasingly smaller and having more and more functions), mounting, cost ....

  This is expected, generally, at least one USB connector, an audio connector and a power connector.

  FIG. 1A illustrates the conventional connections between a USB block and a connector 111. The VBUS pin of the connector 111 is connected to a regulator 112. This regulator 112 makes it possible in particular to deliver an invariable voltage at the output, even when the supply voltage ( in principle equal to 5V) varies.

  The connector 111 also includes pins D- and D +, assigned to the transport of the data. The ID pin allows the connector to detect which device it is connected to, each device being differentiated by a unique number (ID) on the string.

  Finally, the GND pin of the connector 111 is connected to ground.

  Figure 1B illustrates an audio connector 113 according to the prior art and its connections to the incoming and outgoing audio signals.

  According to the prior art, a radiotelephone also comprises a connector for serial data transfer and downloading links, for example of the RS232 type.

  Such a connector generally includes pins of type: -VBATT: this pin can convey a VBATT type signal (for the sake of clarity, the pins and signals carried by the cables connected to the pins have the same name, which is the name standard for the person skilled in the art) supplying a supply voltage to the internal components of the data transfer / download cable (English DatalDownload cable); - CHG-IN: this charging pin is used to wake up the radio when it is off; -RTS / CTS / RXD / TXD: these pins are used for the transmission of RS 232 type signals between the radiotelephone and a terminal, for example of the external processor or computer type. These pins are connected to a processing module via resistors, for example 100 ohms; ADT & BOOT: ADT pin (Accessory Detect) is an analog input to detect the device connected to the connector in ADT mode (data transfer cable, download, ...). The BOOT pin corresponds to a digital input for switching the radiotelephone 20 in BOOT mode. BOOT mode allows the download of a program on the radiotelephone. The pins BOOT and ADT are also connected to resistors, themselves connected to the ground, selectively allowing implementation of the DATA mode or the BOOT mode.

  Thus, according to the prior art, a large number of connectors and connections are necessary in a radiotelephone to allow access to different types of functions.

  A first solution has been proposed, proposing to add all these different pins (VBUS, D +, ID, VBATT, CHG_IN, RTS, HPL, HPCM, MIC_EXT, ...) to a single input / output connector. Such a connector then comprises pins allowing for example RS232, USB, GC20, audio, download, charging a battery (charging).

  However, a disadvantage of this technique is that, although the number of connectors is greatly reduced (only one connector implemented), it comprises a very high number of pins. Indeed, each connection to a device or a particular feature typically requires between 5 and 10 pins at the connector.

  A second solution has been proposed, known as OTG 20 USB for USB On the Go, or CEA-936.

  This second technique makes it possible to minimize the number of connections of a connector in a radiotelephone. However, this technique is specific to USB, audio (unbalanced), RS232 and I2C links.

  Thus, a major disadvantage of this technique is that it does not allow to put all the possible features at the level of the radiotelephone. Thus, it does not allow connection to download devices, charging a battery, listening to stereo through a headset, ....

  The interoperability of the connector is therefore very small, and several different connectors are needed on the radiotelephone.

  3. OBJECTIVES OF THE INVENTION The object of the invention is notably to overcome these disadvantages of the prior art.

  More specifically, an object of the invention is to provide a technique for reducing the number of connectors in a radiotelephone.

  Another objective of the invention is to propose such a technique which also makes it possible to reduce the number of connections, without loss of functionality of the radiotelephone, that is to say without reducing the interoperability.

  The invention also aims to provide such a technique that is simple to implement and inexpensive.

  Yet another object of the invention is to propose such an efficient technique which consumes little surface and is easily integrated in an electronic circuit or on a printed circuit.

  4. ESSENTIAL CHARACTERISTICS OF THE INVENTION These objectives, as well as others which will appear later, are achieved by means of a connector for radiotelephone, comprising a plurality of pins.

  According to the invention, such a connector comprises a first set of pins comprising at least two pins connected to a switch for interconnecting each of the pins of said first set to at least two separate internal signals of the radiotelephone.

  Thus, the invention is based on a completely new and inventive approach to the use of a single connector in a radiotelephone, and a switch, so as to reduce the number of connections necessary to perform the various functions that can be envisaged in a radiotelephone (transfer or download of data, charge of a battery, transmission of audio signals, 25.).

  To do this, the invention proposes to multiplex the data assigned to certain pins implementing different functionalities, such as a connection to a USB interface, a data transfer / download cable, and an earphone and / or a microphone. . ..

  It should be noted that this multiplexing is not obvious, since some signals can not be multiplexed because of a high current. In addition, the pins of a conventional connector are generally powered with a current of 250mA, while a transmission in USB format requires a current of 500mA.

  The switch thus makes it possible to interconnect each of the pins of a first set of pins to signals that are distinct from the radiotelephone.

  Advantageously, the pins of the first set are assigned to digital internal signals for data transfer and / or data download.

  Preferably, the connector allows the implementation of at least one of the functions belonging to the group comprising: a data download in a format of RS232 type; a data transfer in an RS232 type format; a data transfer in a USB type format; - a charge of a battery; transmission of outgoing audio signals; transmission of incoming audio signals; - a serial transmission type I2C.

  The connector according to the invention thus allows the implementation of a large number of functions of different types while reducing the number of connections compared to the techniques of the prior art.

  According to a first embodiment, the connector also comprises a second set of pins comprising at least two pins assigned to the transmission of the same supply voltage, and a third set of pins comprising at least two pins assigned to ground.

  Thus, for example, the second set of pins comprises two pins assigned to the transmission of a VBATT type signal supplying a supply voltage to the internal components of the data transfer / download cable. ), and the third set of pins comprises two pins assigned GND ground.

  Advantageously, the connector comprises a fourth set of pins, comprising at least two pins assigned to an alarm clock of said radiotelephone.

  This fourth set of pins is for example assigned to the transmission of a signal type CHG-IN, used to wake up the radiotelephone when it is off.

  Preferably, the connector comprises means for detecting at least one predetermined function.

  These detection means are for example connected to a pin of the connector. They can in particular take into account the value of at least one resistance so as to determine the detected function.

  This detected function belongs for example to the group comprising: the detection of a download cable; - the detection of a data cable; - the detection of a listener; detection of a microphone; - the detection of a power supply; - the detection of a USB cable.

  Advantageously, the connector is connected to microcontroller 20 comprising means for measuring said value of the resistance.

  The connector according to the invention is also remarkable in that it is connected to at least one USB protection module, comprising at least one pull-up type resistor.

  This USB protection module provides in particular an emulation of a signal SDA (serial data English for serial data) of a bus 12C (English Inter-Integrated Circuit).

  According to this first embodiment, the connector comprises 11 pins. The first set of pins comprises for example 4 pins: a first set connected to at least one RTS signal and a multiplexed HPL signal; a second connected to at least one CTS signal and a multiplexed HPR signal; a third connected to at least one RXD signal, a D + signal and a multiplexed HPCM signal; a fourth connected to at least one TXD signal, a D- signal, and a multiplexed MIC_EXT signal; the signals RTS, CTS, RXD, TXD allowing RS232 type communication between the radiotelephone and at least one processor; signals D + and D- carrying a voltage; the signals HPL, HPR, HPCM, MIC_EXT, allowing the connection to at least one earphone and / or at least one microphone.

  According to a second embodiment, the connector comprises 5 pins. This second embodiment can be implemented on an electronic circuit having at least one test zone.

  Preferably, this test zone comprises access points and / or any connector.

  Advantageously, the access points and / or the connector are connected to at least one of the elements belonging to the following group: a supply voltage; - the mass; an alarm clock of said radiotelephone; an RS232 type communication signal between said radiotelephone and at least one processor; a signal for detecting a function.

  The radiotelephone connector according to the invention may for example be of the USB mini B type. This type of connector has the advantage of being compatible with the USB OTG standard.

  The invention also relates to an electronic circuit intended to be mounted in a radiotelephone, comprising at least one connector as described above.

  The invention also relates to a radiotelephone comprising a connector as described above, and a cable comprising connection means to such a connector.

  Thus, the connector can be connected to a cable and / or a radiotelephone, thus forming a connection assembly.

  5. List of Figures Other features and advantages of the invention will appear more clearly on reading the following description of a preferred embodiment, given as a simple illustrative and nonlimiting example, and the accompanying drawings, among which: FIGS. 1A and 1B, already presented in connection with the prior art, show the connections between a USB block and a connector (1A) and the connections between a stereo headset and a connector (1B) according to the prior art; FIG. 2 illustrates a first embodiment of the invention, showing the connections implemented in an electronic circuit present in a radiotelephone; FIG. 3 shows a technique of USB pin connections and data transfer / download pins implemented in the circuit of FIG. 2; FIG. 4 illustrates the implementation of the BOOT and ADT functionalities on the same pin; FIG. 5 presents a second embodiment of the invention; FIG. 6 illustrates a variant of the second embodiment, in which the USB bus is used for the download mode; FIGS. 7A and 7B show an electronic circuit implemented in a radiotelephone according to a technique of the prior art (7A) and according to the invention (7B), when the second embodiment is implemented.

  DESCRIPTION OF AN EMBODIMENT OF THE INVENTION The general principle of the invention is based on a particular distribution, in a connector, of the different pins necessary for the implementation of the different functionalities in a radiotelephone.

  More specifically, the invention proposes to reduce the number of connectors and the number of connections by grouping certain pins conventionally used for a particular function, in particular by means of a switch.

  According to a first embodiment of the invention, illustrated in FIG. 2, a single connector 21 allows access to certain functionalities, including (among others): the downloading of data over an RS232 link; data transfer over an RS232 link; data transfer on a USB link; the charge of a battery; the transmission of outgoing stereo or differential audio signals; the transmission of unbalanced audio signals (single ended) or incoming differentials; - the serial transmission type I2C.

  This connector 21 is in particular connected to a module 23 providing the essential functions of a radiotelephone, and in particular signal processing, to headphones 24 and to a microphone 25, via a switch SWITCH 22.

  According to this first embodiment of the invention, the various pins necessary for the implementation of such functionalities are grouped together, so as to obtain a connector comprising only 11 pins.

  In order to reduce the number of pins at the connector, the invention notably proposes to multiplex certain pins implementing different functionalities, such as a connection to a USB interface, a data transfer / download cable, an earphone and / or or a microphone.

  It should be noted that this multiplexing is not obvious, since some signals can not be multiplexed because of a high current. In addition, the pins of a conventional connector are usually powered with a current of 250mA, while the USB signal requires a current of 500mA.

  A summary table of the various pins used for these functionalities, and their grouping on 11 pins of a connector according to the invention, according to their assignments, is thus presented: Pin Functionality Functionality Functionality Multiplexing Transfer / USB download earphone possible? 1 VBATT No 2 VBATT No 3 CHG_IN VBUS No 4 CHGIN No RTS HPL Yes 6 CTS HPR Yes 7 RXD D + HPCM Yes 8 TXD D- MIC_EXT Yes 9 ADT / BOOT ID HEAD_DETECT No GND No 11 GND No The roles of these different pins are defined above, in relation with FIGS. 1A and 1B presenting the techniques of the prior art.

  Thus, a first set of pins includes pins 5, 6, 7 and 8, connected to a switch 22, for interconnecting each of these pins to signals from the radiotelephone.

  The connector 21 also comprises: - a second set of pins comprising the pins 1 and 2 assigned to the transmission of an output voltage for the VBATT radiotelephone; a third set of pins including pins 10 and 11 assigned to the ground; a fourth set of pins, including pins 3 and 4 assigned to transmit an input voltage for the radiotelephone (wakeup) CHG_IN - VBUS; a fifth set of pins, including pin 9, assigned to the detection of the device.

  The switch 22 thus allows the multiplexing of audio signals with signals conveyed on the USB cables and on the data transfer / download cables coming from the pins 5, 6, 7 and 8 of the first set of pins.

  Such a switch is for example the STG3699 of the company ST Micro Electronics (registered trademarks).

  It is noted that the connection between the pins RXD and TXD (implementing the data transmission on the data transfer / download cable), and the pins D + and D- (implementing the data transmission on the USB cable), is not obvious, and requires the addition of a 100-ohm resistor between the RXD pin and the D + pin, and a 100-ohm resistor between the TXD pin and the D-pin.

  The four RTS / CTS / RXD / TXD pins are also connected to the module 23 via four 100-ohm resistors.

  As illustrated in connection with FIG. 3, the RXD / TDX pins can be considered as inputs / outputs of the radiotelephone (GPIO) of the General Purpose Input / Output (GPIO).

  In particular, this GPIO mode can be used to emulate a 12C bus (SDA / SCL of the serial data serial port for serial data / serial clock). The SDA signal must then be emulated on the D + connection, using a pull-up resistor 31 of 1.5 Kohms, added to a USB protection module.

  As illustrated in FIG. 4, the module 23 presents two ADT and BOOT signals crossing several resistors so as to combine, at the level of the connector 21, the BOOT and ADT pins allowing the serial links for data transfer and download.

  Thus, to implement the downloading of a program on the radiotelephone (BOOT mode), the value of the resistor R 41, directly connected to the output ADT of the module 23, must be less than 5Kohms.

  If the value of the resistor R is greater than 5Kohms, it is possible to detect the device connected to the connector 21.

For example:

  if R = 1 Kohms, the connection to a download cable is detected (before the radiotelephone is turned on); - if R = 15Kohms, the connection to a data transfer cable is detected (requires the ignition of the radiotelephone); if R = 2.2Kohms, which corresponds to the value of the internal resistance of the microphone, the connection to an earphone is detected, after the radiotelephone is turned on; if R = lOKohms, the connection to a charger is detected (whether the radiotelephone is on or off); if R = 56Kohms, the connection to a USB cable is detected.

  The value of the resistor R thus makes it possible to select the BOOT mode or the ADT mode. The module 23 thus preferably comprises means for measuring the value of the resistor R present on its branch ADT, and associates a connection type with a given resistance value.

  It seems desirable, according to the invention, that the download mode (BOOT mode) is the first implemented, insofar as it operates even when the radiotelephone is off.

  To do this, it suffices that the control logic of the switch 22 is respected. Thus, if the selected switch 22 is of type STG3699, the IN pin of this switch must be low, and connected to ground via a pull-down resistor 100 of 100 Kohms.

  Moreover, according to existing techniques, a dedicated GPIO interface is used to detect the presence of the earphones and / or the microphone. 15

  According to the invention, the GPIO interface 27 directly enables the switch 22 to be controlled.

  The second embodiment of a single connector 51 according to the invention is now presented with reference to FIG.

  This second embodiment makes it possible in particular to further reduce the number of connections of the connector 51, by using a connector resistant to a high current.

  This connector 51 is in particular connected to a module 52, to headphones 24, to a microphone 25, and to a test zone 53, via a SWITCH switch 54, in an electronic circuit 57.

  According to an embodiment, the connector 51 comprises 5 pins: a first pin 3 allowing the inputs / outputs of the HPCM signals to the switch 54, CHG_IN and VBUS; a second pin 7 connected to the switch 54 allowing the inputs / outputs of the signals HPR and D +; a third pin 8 connected to the switch 54 allowing the inputs / outputs of the signals HPL and D-; a fourth pin 9 also connected to the switch 54 allowing the inputs / outputs of the signals MIX_EXT, ID and ADT; a last pin connected to ground GND.

  The switch 54 notably allows the multiplexing of audio signals with signals carried on the USB cables and on the data transfer / download cables coming from the pins 3, 7, 8 and 9 of the connector 51.

  According to this second embodiment, the electronic circuit 57, for example a printed circuit, comprises a test zone 53, comprising access points (test points) or any connector.

  The VBATT signal is moreover essentially used to turn on the radiotelephone from the connector 51, it is not necessary to connect it to the connector 51 if a battery is used, or if a test point is available on the electronic circuit.

  It is thus possible to add several test points in the test zone 53, in particular for the download (RTS, CTS, RXD, TXD) and to use the D + and D- connections for the data transfer at the connector 51.

  It is also possible to add a USB connection for the data transfer: thus, by modifying the operating principle of the download, one can implement the BOOT mode from an RS232 link, and download the data from a USB link.

  The example presented in FIG. 5 notably implements the invention by using a USB mini B type connector (2.0 or OTG) supporting a current of the order of 1A. Such a connector is in particular compatible with the USB OTG standard.

  The improvements presented for the implementation of the first embodiment (for example in FIGS. 3 and 4) can also be implemented in this second embodiment.

  Thus, the electronic circuit 57 makes it possible to use a connector 51, for example of USB type, comprising only 5 pins, and working with a switch 54.

  The invention thus makes it possible to reduce the number of connections and connectors used, since it does not require the use of connectors dedicated to audio signals (jack connector), EMI filters (for protecting the circuit against electromagnetic disturbances). ), ESD diodes (to protect the circuit against electrostatic discharge) for headphones ...

  The circuit according to the invention thus benefits from improved immunity to electrostatic (ESD) or electromagnetic (EMI) discharges, by reducing the number of connections on the connector.

  The invention notably allows a better radiofrequency immunity when using differential incoming and outgoing audio signals.

  An embodiment variant in which the multiplexed USB bus for the download mode is used is now presented in connection with FIG.

  Incoming and outgoing signals are thus used in an RS232-type connection for downloading the boot code, in which the USB driver is included, and then USB connection is used, in order to benefit from a very fast download, the order of 12 Mbit / s.

  This variant is based on the use of a cable and a simple microcontroller, to emulate the RS232 link via a USB protocol, and automatically switch to the USB link when the boot code is downloaded.

  The invention thus has many advantages, and implements a combination of analog and / or digital type signals of different powers, for example using a switch.

  FIGS. 7A and 7B also show the electronic circuit implemented in a radiotelephone according to a technique of the prior art (7A) and according to the invention (7B), when the second embodiment is put into operation. implemented.

  Thus, in FIG. 7A, the connector comprises 18 pins, and requires the implementation of an EMI filter.

  In Fig. 7B, the 18-pin connector is replaced by a 5-pin connector, for example of the USB Mini B type, the EMI filter is removed, and a switch is added. The multiplexed USB bus can also be implemented for download mode.

  Note in particular that the solution according to the invention allows a reduction of the surface of the electronic circuit, and therefore allows, for example, the reduction of the size of the radiotelephone, or the addition of new features.

  The invention thus makes it possible to develop an electronic circuit that is simpler and less consumer in terms of surface area.

  The invention also allows a cost reduction since it requires fewer components, and reuses the existing cables.

Claims (20)

  A radiotelephone connector, comprising a plurality of pins, characterized in that it comprises a first set of pins comprising at least two pins connected to a switch for interconnecting each of the pins of said first set to at least two distinct internal signals. said radiotelephone.   2. Radiotelephone connector according to claim 1, characterized in that the pins of said first set of pins are assigned to digital internal signals for data transfer and / or data download.   3. Radiotelephone connector according to any one of claims 1 and 2, characterized in that it allows the implementation of at least one of the functions belonging to the group: - data download in a format of RS232 type; - data transfer in an RS232 type format; - data transfer in a USB type format; charging a battery; - transmission of outgoing audio signals; transmission of incoming audio signals; - serial transmission type I2C.   4. A radiotelephone connector according to any one of claims 1 to 3, characterized in that said first set of pins comprises: - a first pin connected to at least one RTS signal and a multiplexed HPL signal; a second pin connected to at least one CTS signal and a multiplexed HPR signal; a third pin connected to at least one RXD signal, a D + signal and a multiplexed HPCM signal; a fourth pin connected to at least one TXD signal, a D- signal, and a multiplexed MIC_EXT signal; Said RTS, CTS, RXD, TXD signals enabling RS232 type communication between said radiotelephone and at least one processor; said D + and D- signals carrying a voltage; said HPL signals, HPR, HPCM, MIC_EXT, allowing the connection to at least one earphone and / or at least one microphone.   5. radiotelephone connector according to any one of claims 1 to 4, characterized in that it comprises: - a second set of pins comprising at least two pins assigned to the transmission of the same supply voltage; a third set of pins comprising at least two pins assigned to ground.   6. radiotelephone connector according to claim 5, characterized in that it comprises a fourth set of pins, comprising at least two pins assigned to an alarm of said radiotelephone.   7. Radiotelephone connector according to any one of claims 5 and 6, characterized in that it comprises means for detecting at least one predetermined function.   8. Radiotelephone connector according to claim 7, characterized in that said means for detecting a function take into account the value of at least one resistor.   9. Radiotelephone connector according to any one of claims 7 and 8, characterized in that said detection belongs to the group comprising: detection of a download cable; - detection of a data cable; detecting a listener; detection of a microphone; detection of a power supply; - detection of a USB cable.   10. Connector for radiotelephone according to any one of claims 8 and 9, characterized in that it is connected to at least one microcontroller, said microcontroller comprising means for measuring said value of the resistance.   11. Radiotelephone connector according to any one of claims 5 to 10, characterized in that it is connected to at least one USB protection module, comprising at least one pull-up type resistor.   12. Radiotelephone connector according to claim 11, characterized in that said USB protection module provides emulation of an SDA signal of an I2C bus.   13. Connector for radiotelephone according to any one of claims 5 to 12, characterized in that it comprises 11 pins.   Radiotelephone connector according to any one of claims 1 to 3, characterized in that it comprises 5 pins.   15. connector for radiotelephone according to claim 14, characterized in that it is implemented on an electronic circuit further having at least one access point.   16. radiotelephone connector according to claim 15, characterized in that said access points are connected to at least one of the elements belonging to the following group: - a supply voltage; the mass; an alarm clock of said radiotelephone; an RS232 type communication signal between said radiotelephone and at least one processor; a signal for detecting a function.   17. Radiotelephone connector according to any one of claims 1 to 16, characterized in that it is USB mini B type. An electronic circuit intended to be mounted in a radiotelephone, characterized in that it comprises at least one connector comprising a plurality of pins and a switch, said connector comprising a first set of pins comprising at least two pins connected to said switch allowing interconnecting each of the pins of said first set to at least two separate internal signals of said radiotelephone.   19. Radiotelephone characterized in that it comprises a connector according to any one of claims 1 to 17.   20. Cable characterized in that it comprises connection means to a connector according to any one of claims 1 to 17.