Abstract:
Provided is a microphone compatibility device comprising a sensor that detects a voltage along a conductive path between a microphone and at least one electronic device and a current control device that draws current for permitting microphone detection by each of a first electronic device and a second electronic device. The second electronic device has a lower current draw requirement than the first electronic device.

Description:
BACKGROUND 
     This description relates generally to microphones for electronic devices, and more specifically, to systems and methods that provide microphone compatibility between different electronic devices. 
     BRIEF SUMMARY 
     In a general aspect, provided is a microphone compatibility device, comprising: a sensor that detects a voltage along a conductive path between a microphone and an electronic device of a first or second type; and a regulator that draws current for satisfying a microphone detection current draw requirement of the first type of electronic device, and that prevents a current draw for the second type of electronic device having a lower microphone detection current draw requirement than the microphone detection current draw requirement of the first type of electronic device. 
     Aspects may include one or more of the following features: 
     The regulator may include a voltage controlled current shunt. 
     The detected voltage may be greater than a predetermined voltage, and the current may be drawn by the regulator when the detected voltage is greater than the predetermined voltage. 
     The predetermined voltage may be greater than a minimum voltage supply of the electronic device. 
     The microphone compatibility device may further comprise a current limiter that controls an amount of current through the regulator according to device requirements. 
     The regulator may draw the current from time of a connection or enabling event to a time of a physical disconnection or disabling event between the microphone and the second electronic device. 
     In another general aspect, provided is a microphone compatibility device, comprising: a sensor that detects a voltage along a conductive path formed at an initial time between a microphone and an electronic device; a timer that establishes a period of time after the initial time during which additional current is drawn; and a shunt device that shunts a current so that the additional current is drawn during the period of time after the initial time. 
     Aspects may include one or more of the following features: 
     The electronic device may require the additional current to be drawn in order to detect the microphone. 
     The electronic device may not require the additional current to be drawn in order to detect the microphone, and wherein the microphone is activated after the period of time. 
     The microphone compatibility device may further comprise a reset device that resets the device after a physical disconnection or disabling event affecting a transfer of voltage between the microphone and the electronic device. 
     The timer may include an RC circuit, and the reset device drains the capacitor after the physical connection or disabling event. 
     In another general aspect, a microphone compatibility device, comprises a sensor that detects a voltage along a conductive path between a microphone and at least one electronic device; and a current control device that draws current for permitting microphone detection by each of a first electronic device and a second electronic device, the second electronic device having a lower current draw requirement than the first electronic device. 
     Aspects may include one or more of the following features: 
     The current control device may include a regulator that draws current for satisfying a microphone detection current draw requirement of a first electronic device, and that prevents a current draw for the second electronic device. 
     The regulator may include a voltage controlled current shunt. 
     The detected voltage may be greater than a predetermined voltage, and the current may be drawn by the regulator when the detected voltage is greater than the predetermined voltage. 
     The microphone compatibility device may further comprise a current limiter that controls an amount of current through the regulator according to device requirements. 
     The regulator may draw the current from time of a connection or enabling event to a time of a physical disconnection or disabling event between the microphone and the second electronic device. 
     The current control device may include a timer that establishes a period of time after the initial time during which additional current is drawn and a shunt device that shunts a current so that the additional current is drawn during the period of time after the initial time. 
     The second electronic device may not require the additional current to be drawn in order to detect the microphone, and the microphone may be activated after the period of time. 
     The microphone compatibility device may further comprise a reset device that resets the device after a physical disconnection or disabling event affecting a transfer of voltage between the microphone and the first or second electronic device. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The above and further advantages may be better understood by referring to the following description in conjunction with the accompanying drawings, in which like numerals indicate like structural elements and features in various figures. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of features and implementations. 
         FIG. 1  is a block diagram of a microphone compatibility system, in accordance with some examples. 
         FIG. 2  is a block diagram of a microphone compatibility device, in accordance with some embodiments. 
         FIGS. 3A and 3B  are electrical circuit diagrams, each illustrating a simplified model of a microphone and an electronic device, in accordance with some embodiments. 
         FIG. 4  is a flow diagram of a method for a controlled current draw for microphone compatibility, in accordance with some embodiments. 
         FIG. 5  is a block diagram of a microphone compatibility device, in accordance with some embodiments. 
         FIG. 6  is a flow diagram of a method for a controlled current draw for microphone compatibility, in accordance with some embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Microphones are readily used by smartphones or other mobile electronic devices for providing voice commands. However, some devices provide a microphone detection scheme that requires a significant current draw in order detect a microphone, while other devices require support for low bias voltage microphones that do not draw a significant amount of current, and require low current consumption to operate properly at all possible microphone bias voltages. Incompatibility issues may arise due to the inability of the same microphone to be detected by some devices requiring a high current draw such as Apple iOS devices, while maintaining low power operation required by other devices requiring low bias voltage microphones that draw low current, such as Samsung devices executing an Android operating system. 
       FIG. 1  is a block diagram of a microphone compatibility system, in accordance with some examples. 
     A microphone compatibility device  16  is connected to a circuit between a microphone  12  and an electronic device  10 . Where their grounds are common, the compatibility device  16  is in parallel to the microphone  12 . The electronic device  10  requires a predetermined current consumption for the microphone  12  to operate with the device  10 . During operation, the microphone  12  receives sound waves and modulates the amount of current electricity flowing through the microphone, and therefore the voltage on the microphone input, which is detected by the microphone compatibility device  16 . The microphone  12  may be a microelectromechanical systems (MEMS) microphone or the like. However, other microphone types can equally apply. The electronic device  10  can be a portable computer such as a smartphone, laptop computer, notepad computer, and so on. The electronic device  10  includes an input port, such as an audio or microphone input for receiving an electric current from the microphone  12 . The input port is commonly a single terminal of a combined input/output jack, with a ground terminal shared between input and output. 
     The microphone compatibility device  16  adjusts or compensates for the current consumption requirements of different electronic devices. For example, the microphone compatibility device  16  may allow a microphone  12  to support a range of bias voltages required by one device specification, for example, devices running a mobile operating system such as Android™, and also be compatible with other devices with high current consumption requirements. Here, the microphone  12  may be permitted to pass detection tests of different devices, regardless of power requirements. In some embodiments, the microphone compatibility device  16  can be constructed and arranged to consume additional power when detected by an iOS device. In some embodiments, the microphone compatibility device  16  consumes extra power at higher voltages only when the microphone  12  can accommodate for the higher voltages. In other embodiments, the microphone compatibility device  16  consumes extra power only briefly during detection after connection to an electronic device, after which the device  16  returns to a low power operation. 
       FIG. 2  is a block diagram of a microphone compatibility device  16 A, in accordance with some embodiments. The microphone compatibility device  16 A can function as a voltage-dependent current shunt, whereby current is drawn from an electronic device requiring high current consumption for detecting the microphone  12 , and maintaining a bias voltage for electronic devices requiring lower voltages and that wouldn&#39;t draw enough current otherwise required by the high current draw devices. 
     The microphone compatibility device  16 A is constructed and arranged to draw additional current when connected to a device having a detection scheme requiring a significant amount of current for detecting a microphone, for example, 210 μA-500 μA required by an iOS device for microphone detection. 
     To achieve this, the microphone compatibility device  16 A comprises a sensor  22 , a current limiter  24 , and a voltage regulator  26 . The sensor  22 , current limiter  24 , and/or regulator  26  can be under the housing of a single device as shown in  FIG. 2 , or separated into different devices. The microphone compatibility device  16 A may also include a connector to the microphone  12 , a connector to the electronic device  10 , or a connector to both the microphone  12  and the electronic device  10 . In some cases, the components of the device  16  are on a common PCB with the microphone  12  and connected to it through conductors on the PCB. 
     The voltage sensor  22  is positioned between the microphone  12  and a microphone input at an electronic device  10  so that the sensor  22  can establish whether an electrical connection is made between the microphone  12  and the electronic device  10 . In particular, the voltage sensor  22  monitors a voltage on the line between the microphone  12  and the electronic device  10  and is enabled by the presence of a voltage. 
     The current limiter  24  limits current through the voltage regulator  26 . For example, the current limiter may include a resistor that controls current draw according to device requirements. 
     The voltage regulator  26  provides a stable voltage and serves as a shunt regulator for drawing extra current in particular from a device  10  for detection, for example, iOS devices, when a determination is made that the sensor  22  detects a connection between the microphone  12  and an electronic device  10 . As previously described, some devices may require support for very low bias voltage microphones that don&#39;t draw a high amount of current, while other devices require a high current draw in order to detect a microphone. The voltage regulator  26  can provide a current sink so that the microphone compatibility device  16 A can accommodate either device type. 
     For example, referring to  FIGS. 3A and 3B , two electronic devices (Device  1 , Device  2 ) may each have different specification electrical parameters shown in Table 1. In some embodiments, Device  1  may execute an Android™ operating system, and Device  2  may execute an iOS operating system. 
     
       
         
               
               
               
             
               
               
               
               
             
           
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 Device 1 
                 Device 2 
               
               
                   
                   
               
             
             
               
                   
               
             
          
           
               
                   
                 Mic Bias Voltage 
                 1.8 V-2.9 V 
                 2.7 V 
               
               
                   
                 Mic Bias Resister 
                 2.21 kΩ 
                 2.21 kΩ 
               
               
                   
                 MEMS Vsupply (Minimum) 
                 1.5 V 
                 1.5 V 
               
               
                   
                 Microphone Current 
                 &lt;136 μA 
                 210 μA-500 μA 
               
               
                   
                   
               
             
          
         
       
     
     As shown in Table 1 and  FIG. 3A , Device  1  requires a microphone current of no more than 136 μA in order to maintain a minimum voltage supply (Vsupply), for example, 1.5V. On the other hand, Device  2  requires a high amount of current (210 μA-500 μA) required by Device  2  for microphone detection. 
     At  FIG. 3A , when a lower voltage is detected, for example, 1.8V, and the microphone compatibility device  16 A does not draw additional current so that microphone  12  may operate with Device  1 . Here, the microphone current required to maintain the Vsupply voltage at 1.5V bias is less than 136 μA. As described above, Device  1  requires support for low bias voltage microphones. 
     At  FIG. 3B , Device  2  requires a microphone current that is significantly greater than that of Device  1 , for example, 210 μA-500 μA, for microphone detection. The microphone compatibility device  16 A is activated here to provide sufficient current to Device  2  requiring high current consumption for detecting the microphone  12 . 
     Referring to Table 1 illustrated by way of example above, a microphone may have a minimum Vsupply limit of 1.5V, and will turn off if its voltage drops below this minimum voltage. Depending on the electronic device&#39;s output voltage, e.g., 1.8-2.9V, the output voltage may be close to the minimum voltage. As previously described, additional current must be drawn to be detected by Device  2 . However, this can only be achieved if the Vsupply is higher than the minimum voltage (e.g., 1.5V). In embodiments where an electronic device operates at a sufficient voltage, for example, 2.7V, the microphone compatibility device  16 A can draw extra current when a voltage above a predetermined voltage, e.g., 2.0V, is detected. 
       FIG. 4  is a flow diagram of a method  100  for a controlled current draw for microphone compatibility, in accordance with some embodiments. In describing the method  100 , reference is made to elements of  FIGS. 1-3 . 
     At block  102 , the microphone  12  is directly or indirectly coupled to an electronic device  10 . The electronic device  10  may include a microphone detection scheme that requires significant current consumption to detect the microphone  12 , or require low current consumption to operate properly at all possible microphone bias voltages. When the microphone  12  establishes the electronic device  10  in this manner, an electrical path is formed whereby current flows between the microphone  12  and the electronic device  10 . 
     Some electronic devices  10  may execute a microphone detection process. At decision diamond  106 , a determination is made whether the device requires a high current draw to detect the microphone  12 . If yes, then the method  100  proceeds to block  108  where the current between the microphone  12  and the electronic device  10  is controlled so that the device&#39;s microphone detection requirements are satisfied with respect to current draw. Here, current can be drawn indefinitely until disconnection. Otherwise, the method  100  proceeds to block  110 , where a low current draw device  10  is connected to the microphone  12 . Here, the voltage dependent current shunt doesn&#39;t draw current so no additional power is consumed, and the microphone operates with the low current draw device  10 . 
       FIG. 5  is a block diagram of a microphone compatibility device  16 B, in accordance with some embodiments. The microphone compatibility device  16 B can function as a timed current shunt, whereby sufficient current is provided to an electronic device requiring high current consumption only briefly during detection of the microphone  12 , whereby low power operation subsequently occurs. 
     The microphone compatibility device  16 B comprises a sensor  42 , a timer  44 , a shut device  46 , and a reset device  48 . The sensor  42 , timer  44 , shunt device  46 , and reset device  48  can be under the housing of a same device as shown in  FIG. 5 , or separated into different devices. The microphone compatibility device  16 B may also include a connector to the microphone  12 , a connector to the electronic device  10 , or a connector to both the microphone  12  and the electronic device  16 . 
     The sensor  42  is parallel the microphone  12  and a microphone input at an electronic device  10  so that the sensor  42  can establish whether an electrical connection is made between the microphone  12  and the electronic device  10 . 
     The timer  44  permits extra power to be consumed briefly during detection. The timer  44  establishes a time, for example, 40 ms, during which a microphone detection process may be executed at the electronic device  10 . 
     The shunt device  46  shunts current for the predetermined duration, for example, 40 ms. after the initial physical connection with the device  10 . As previously described, some devices may require support for very low bias voltage microphones that don&#39;t draw a high amount of current, while other devices require a high current draw in order to detect a microphone. The microphone compatibility device  16 B can accommodate for either device type. 
     Referring again to Table 1, microphone compatibility device  16 B provides a timing scheme, for example, whereby extra power is drawn for a predetermined time, for example, 40 ms, after connection to the device, e.g., Device  1  or Device  2 . This amount of time is sufficient to be detected by Device  2 . On the other hand, the activation of the microphone  12  for Device  1  is slightly delayed. 
     In sum, the microphone compatibility device  16 B can operate with Device  1  and Device  2  shown in  FIGS. 3A and 3B , respectively, and used to draw extra current when Device  1  is connected, so that it detects the microphone  12  coupled to Device  1 . With regard to Device  2 , extra current is drawn when a lower voltage is applied by Device  2 . 
     The reset device  48  permits the microphone compatibility device  16 B to be reset after an unplug or disabling event such as a button press related to the connection between the microphone  12  and the electronic device  10 . The reset device  48  resets the timer  44 , for example, after the microphone compatibility device  16 B is disconnected from the device  10 . In embodiments where the timer  44  includes an RC circuit, the reset device  48  may include a diode or related device to quickly drain the capacitor in the timer  44  after physical disconnection, or other event such as pressing a button in lieu of a physical disconnection affecting a transfer of voltage between the microphone  12  and the electronic device  10 . The voltage provided may be used to drive the RC timer. In other embodiments, the RC timer begins charging or “counting” immediately upon connection. 
       FIG. 6  is a flow diagram of a method  200  for a controlled current draw for microphone compatibility, in accordance with some embodiments. In describing the method  200 , reference is made to elements of  FIGS. 1 and 5 . 
     At block  202 , the microphone  12  is directly or indirectly coupled to an electronic device  10 . The electronic device  10  may include a microphone detection scheme that requires significant current consumption to detect the microphone  12 , or require low current consumption to operate properly at all possible microphone bias voltages. When the microphone  12  establishes the electronic device  10  in this manner, an electrical path is formed whereby current flows between the microphone  12  and the electronic device  10 . Sensor  42  may detect a voltage on the path. 
     At block  204 , the timer  44  is activated, for example, described above with respect to  FIG. 5 . 
     At block  206 , current between the microphone  12  and the electronic device  10  is shunted for a predetermined period of time for microphone detection to occur, for example, 40 ms. 
     At block  208 , the timer  44  is stopped. 
     At block  210 , the microphone compatibility device  16 B returns to low power operation. 
     A number of implementations have been described. Nevertheless, it will be understood that the foregoing description is intended to illustrate and not to limit the scope of the inventive concepts which are defined by the scope of the claims. Other examples are within the scope of the following claims.