Patent Description:
With the advent of modern portable electronic devices such as two-way radios, smart telephones, and other communication devices, end users demand increasingly complex, power-intensive functionality. Batteries and other portable energy storage methods continue to scale in energy density to meet demand. Methods for interconnecting and charging electronic devices must likewise scale to offer greater performance and connectivity. Legacy portable devices often provide only a simple pair of bare electrical terminals to a charger for recharging the energy storage system, such as a battery, within these devices. Not all chargers provide a direct battery terminal connection, or two-terminal connection, for charging portable devices. Some battery chargers implement a multi- or many-pin interface, such as the universal serial bus, that require more than two electrical connections for charging or communicating with portable devices. As a result, portable devices designed to be charged through a bare two-terminal interface are incompatible with battery chargers that implement a multi- or many-pin electrical interface such as the universal serial bus connector (for example, a USB-C or universal serial bus type-C connector).

<CIT> and <CIT> describe charging devices that are configured to electrically couple to a power source via a USB port.

According to the present invention, a method and a system are provided having the features of the respective independent claims. Preferred embodiments of the invention are subject-matter of the dependent claims.

The accompanying figures, where like reference numerals refer to identical or functionally similar elements throughout the separate views, together with the detailed description below, are incorporated in and form part of the specification, serve to further illustrate embodiments of concepts that include the claimed invention, and explain various principles and advantages of those embodiments.

Two-terminal portable electronic devices are not designed to interface with electronic chargers that implement a multi-pin electrical interface such as a universal serial bus connector. Systems and methods described herein provide, among other things, for the detection of a two-terminal portable electronic device when placed in a multi-pin charger receptacle (for example, a universal serial bus type-C connector) and, after sufficiently coupling to the two-terminal portable electronic device, the subsequent charging of the two-terminal portable electronic device.

Another embodiment provides a charging system for charging a two-terminal portable electronic device. The charging system includes a charger; a multi-pin connector electrically coupled to the charger; and an apparatus electrically coupled to the multi-pin connector. The apparatus includes a detection circuit to detect the two-terminal portable electronic device and electrically couple the two-terminal portable electronic device to the charger when the two-terminal portable electronic device is coupled to the receptacle; and an activation circuit to charge the two-terminal portable electronic device using a configuration channel terminal of the multi-pin connector upon detection of the two-terminal portable electronic device, as set forth in the corresponding independent claim.

Another embodiment provides a method of charging a two-terminal portable electronic device. The method includes detecting, with a detection circuit, the two-terminal portable electronic device and electrically coupling the two-terminal portable electronic device to a multi-pin universal serial bus connector when the two-terminal portable electronic device is coupled to a receptacle provided by a charger. The method also includes charging, with an activation circuit, the two-terminal portable electronic device using a configuration channel terminal of the multi-pin universal serial bus connector upon detection of the two-terminal portable electronic device, as set forth in the corresponding independent claim.

<FIG> is a diagram of a charging system <NUM>, in accordance with some embodiments. The charging system <NUM> includes a two-terminal portable electronic device <NUM>, a device detection circuit <NUM> and the charger <NUM> as shown in <FIG>. As shown in <FIG>, the two-terminal portable electronic device <NUM> is coupled to the device detection circuit <NUM> and the device detection circuit <NUM> is in turn coupled to the charger <NUM>. In some embodiments, the device detection circuit <NUM> is integrated with the charger <NUM>. In some embodiments, the device detection circuit <NUM> is removably coupled to the charger <NUM>. In some embodiments, the device detection circuit <NUM> is integrated within a receptacle such as a pocket that is configured to receive the two-terminal portable electronic device <NUM> and electrically couple to the charger <NUM>.

The two-terminal portable electronic device <NUM> includes an internal impedance <NUM> coupled between negative terminal <NUM> and positive terminal <NUM>. The device detection circuit <NUM> includes terminals <NUM>, <NUM>, <NUM>, <NUM>, and <NUM>. In one example, the terminal <NUM> is coupled to the negative terminal <NUM> and the terminal <NUM> is coupled to the positive terminal <NUM>.

In the example shown, the charger <NUM> is configured to receive power from an alternating current (AC) source (for example, a wall outlet) and convert the power into direct current (DC) power that can be used for charging portable communications devices such as the two-terminal portable electronic device <NUM>. In some embodiments, the charger <NUM> includes a universal serial bus type-C connector <NUM>. The universal serial bus type-C connector <NUM> includes a <NUM>-pin connection of which a first set of <NUM>-pins are used for an upstream connection and a second set of <NUM>-pins are used for a downstream connection. In the example shown in <FIG>, the universal serial bus type-C connector <NUM> includes a negative pin <NUM>, a positive pin <NUM>, and a configuration channel (CC) pin <NUM>. In some embodiments, the negative pin <NUM> is coupled to the terminal <NUM>, the positive pin <NUM> is coupled to the terminal <NUM> and the configuration channel pin <NUM> is coupled to the terminal <NUM>.

In some embodiments, the charging system <NUM> leverages an upstream channel (for example, the configuration channel) of the universal serial bus type-C connector <NUM> by sending information about the two-terminal portable electronic device <NUM> to the charger <NUM> thereby initiating charging of the two-terminal portable electronic device <NUM>. In some embodiments, the charger <NUM> remains powered down for almost all of the time when the two-terminal portable electronic device <NUM> is not coupled or placed in a charging pocket <NUM> (see <FIG>) associated with the charger <NUM>.

<FIG> is a diagram of a charging system <NUM>, in accordance with some embodiments. The charging system <NUM> includes the two-terminal portable electronic device <NUM>, a charging pocket <NUM>, the device detection circuit <NUM> and the charger <NUM> having a universal serial bus type-C connector <NUM>. In one example, the charging pocket <NUM> includes the pocket contact <NUM> and the pocket contact <NUM>. In some embodiments, one end of the pocket contact <NUM> and the pocket contact <NUM> are configured to couple with the negative terminal <NUM> and the positive terminal <NUM>, respectively, when the two-terminal portable electronic device <NUM> is placed in the charging pocket <NUM>. The remaining end of the pocket contact <NUM> and the pocket contact <NUM> are coupled to terminals <NUM> and <NUM>, respectively of the device detection circuit <NUM>. Additionally, device detection circuit <NUM> is coupled to the universal serial bus type-C connector <NUM> using a cable <NUM>.

<FIG> is a block diagram of the device detection circuit <NUM>, in accordance with some embodiments. In the example shown, the device detection circuit <NUM> includes a comparator detection circuit <NUM>, an over-current protection circuit <NUM> and a universal serial bus configuration channel line activation circuit <NUM> (for example, a driver circuit). The comparator detection circuit <NUM> is configured to accurately detect two-terminal portable electronic device <NUM> insertion events. The over-current protection circuit <NUM> engages when the two-terminal portable electronic device <NUM> draws excessive current. In the event the two-terminal portable electronic device <NUM> begins to draw excessive current, the universal serial bus configuration channel line activation circuit <NUM> is deactivated thereby disabling charging of the two-terminal portable electronic device <NUM> until the two-terminal portable electronic device <NUM> that may be malfunctioning is removed. The system recovers automatically after the malfunctioning device is removed.

<FIG> illustrates one example of the device detection circuit <NUM>, in accordance with some embodiments. In some embodiments, the pocket contact <NUM> corresponds to either contact J3 or contact J4 and the pocket contact <NUM> corresponds to either of the contacts J1 and J2. In one example, the device detection circuit <NUM> is coupled to contacts J1, J2, J3, and J4. In some embodiments, one of the pairs of contacts J1, J3, and J2, J4 can be used to interface with the two-terminal portable electronic device <NUM>. In one example, when the two-terminal portable electronic device <NUM> is not placed within the charging pocket <NUM> (shown in <FIG>) there is no electrical connection between the contact J1 and the contact J3. In some embodiments, the internal impedance <NUM> of the two-terminal portable electronic device <NUM> is approximately <NUM> kilo-ohms when the rechargeable battery within the two-terminal portable electronic device <NUM> is fully charged. In some embodiments, the internal impedance <NUM> of the two-terminal portable electronic device <NUM> may be as low as <NUM> ohms when the charge within the rechargeable battery is low. In some embodiments, when the two-terminal portable electronic device <NUM> is placed within the charging pocket <NUM> an electrical connection is established between the pocket contact J1 and the pocket contact J3 and the two-terminal portable electronic device <NUM> is detected by the device detection circuit <NUM>. The device detection circuit <NUM> is powered on a +5V line fed by one of pins of the universal serial bus type-C connector <NUM>. When the two-terminal portable electronic device <NUM> is detected by the device detection circuit <NUM>, the two-terminal portable electronic device <NUM> begins to get charged.

The device detection circuit <NUM> includes a low power comparator U1-A that has two inputs namely a positive input (+) and a negative input (-). In some embodiments, the positive input (+) is coupled to a pocket ground and the negative input (-) is coupled to a reference voltage. In some embodiments, the low power comparator U1-A compares the electrical potential at the positive input and the negative input to determine which of the inputs has a higher electrical potential. In some embodiments, when the positive input (+) is high and the negative input (-) is low, the output of the low power comparator U1-A is high. On the other hand, when the positive input is low and the negative input is high, the output of the low power comparator U1-A is low.

In some embodiments, when the two-terminal portable electronic device <NUM> is not placed in the charging pocket <NUM>, the pocket ground (POCKET GND shown in <FIG>) will be floating and be approximately 0V. The low power comparator U1-A receives at the positive input (+) an input coming through resistor R11 that is essentially zero. Additionally, the low power comparator U1-A receives at the negative input (-) a reference voltage generated by resistor R13 and a cascaded array of transistors Q3, and Q4. The transistors Q3 and Q4 are designed such that the output voltage between them is approximately 25mV and is maintained as a constant reference voltage. As a result, when the device is not placed in the charging pocket <NUM>, the positive input (+) of the low power comparator U1-A has a lower voltage compared to the negative input (-) of the low power comparator U1-A.

When the two-terminal portable electronic device <NUM> is placed in the charging pocket <NUM>, a potential difference develops across internal impedance <NUM> and the voltage at the positive input (+) of the low power comparator U1-A is higher than the reference voltage of 25mV. The low power comparator U1-A drives the output voltage across R12 higher than the instance before the two-terminal portable electronic device <NUM> was placed in the charging pocket <NUM>. The output of resistor R12 is fed to a top portion and a bottom portion of the device detection circuit <NUM>. The bottom portion of the device detection circuit <NUM> provides a communication circuit that provides an upstream connection through transistor Q6 to the charger <NUM>. , The transistor Q6 is enabled to set a voltage on the configuration channel (CC) line of the universal serial bus type-C connector <NUM>. The charger <NUM> monitors the configuration channel (CC) line voltage in real time and waits until the voltage reaches a predetermined window of voltage. When the voltage on the configuration channel (CC) line reaches the predetermined window of voltage, the charger <NUM> determines that there is a two-terminal portable electronic device <NUM> present in the charging pocket <NUM> that needs charging. Consequently, the upstream charger <NUM> is enabled to facilitate charging of the two-terminal portable electronic device <NUM>.

In some embodiments, the top portion of the device detection circuit <NUM> is coupled to the pocket contact J3 and J3 that in turn corresponds to pocket contact <NUM> as shown in <FIG>. The top portion of the device detection circuit <NUM> includes metal-oxide-semiconductor field-effect transistors (MOSFET) Q1 and Q2. In some embodiments, the transistor Q1 is a pull-down, in-channel charging switch. When the output of the low power comparator U1-A is high that allows the current to flow back upstream to the charger <NUM>. In some embodiments, when the device draws excessive current, a potential difference forms at the device negative contact or pocket ground. The potential difference enables the MOSFET, which pulls the comparator output to a GND or low state, disabling the configuration channel (CC). When the malfunctioning device is removed, the circuit automatically resumes normal operation awaiting device detection.

<FIG> illustrates one example of the device detection circuit <NUM>, in accordance with some embodiments. In some embodiments, the device detection circuit <NUM> shown in <FIG> is used to charge a two-terminal portable electronic device <NUM> in a manner similar to that explained in <FIG>. In some embodiments, the device detection circuit <NUM> shown in <FIG> includes a comparator detection circuit <NUM>, an over-current protection circuit <NUM>, and a universal serial bus configuration channel line activation circuit <NUM>. The low power comparator U1-A monitors the impedance of the charging pocket <NUM>. When no two-terminal portable electronic device <NUM> is present in the charging pocket <NUM>, the charging pocket <NUM> is at infinite resistance to ground. The low power comparator's inputs remain at the default low output. When the two-terminal portable electronic device <NUM> with a finite impedance is inserted into the charging pocket <NUM>, the current flows through it and the low power comparator U1-A reads a change in the pocket impedance. The output of the low power comparator U1-A switches to high thereby enabling the universal serial bus configuration channel line activation circuit <NUM>.

In some embodiments, the potential difference across a sense resistor R5 (for example, a <NUM>-ohm resistor) is determined. At idle, the voltages on either side of the sense resistance R5 is equivalent. The input resistance network of the low power comparator U1-A is biased to ensure the "low" input is above the "high" input and the output follows "low" to hold the system "off". In some embodiments, when a device impedance within a range of detection such as a two-terminal portable electronic device <NUM> is inserted into the charging pocket <NUM>, a voltage potential develops across the sense resistor R5. The comparator's inputs are biased such that the "high" input rises above the "low" input potential and the output is set to a "high" state. In some embodiments, the device detection circuit <NUM> provided in <FIG> is capable of detecting device impedances from <NUM> ohm down to as low as <NUM> ohm. In some embodiments, the comparator detection circuit <NUM> is capable of detecting any resistance beneath <NUM>, if the over-current protection circuit <NUM> is removed from the device detection circuit <NUM>.

In some embodiments, over-current protection circuit <NUM> engages when the two-terminal portable electronic device <NUM> in the charging pocket <NUM> draws excessive current. After successful detection of the two-terminal portable electronic device <NUM>, the circuit power holds the transistor Q3 in saturation, or an active "high" state. In some embodiments, when the voltage collapses past a "shutdown" voltage, the circuit power is no longer able to hold Q3 in saturation. When Q3 shuts off, the universal serial bus configuration channel line activation circuit <NUM> is deactivated thereby disabling the circuit output until the two-terminal portable electronic device <NUM> that may be malfunctioning is removed from the charging pocket <NUM>. In some embodiments, the universal serial bus configuration channel line activation circuit <NUM> will auto-recover to idle state upon removal. In some embodiments, the shutdown voltage is configurable using the resistor bias network R16/R18,.

In some embodiments, so long as the two-terminal portable electronic device <NUM> with detectable impedance remains electrically coupled to the pocket contacts and the over-current protection circuit <NUM> does not trip, the device detection circuit <NUM> in <FIG> is latched on and will conduct current to the two-terminal portable electronic device <NUM>.

<FIG> is a flowchart of a method <NUM> of charging a two-terminal portable electronic device <NUM>, in accordance with the invention. At block <NUM>, the method <NUM> includes detecting, with the device detection circuit <NUM>, the two-terminal portable electronic device <NUM> and electrically coupling the two-terminal portable electronic device <NUM> to the multi-pin universal serial bus connector (for example, the universal serial bus type-C connector <NUM>) when the two-terminal portable electronic device <NUM> is coupled to a receptacle (for example, the charging pocket <NUM>) that may be provided by the charger <NUM>. In some embodiments, the device detection circuit <NUM> is powered using configuration channel (CC) line of the universal serial bus type-C connector <NUM> and no other external power source is needed.

At block <NUM>, the method <NUM> includes detecting an internal impedance <NUM> across the negative terminal <NUM> and the positive terminal <NUM> of the two-terminal portable electronic device <NUM>. In some embodiments, the device detection circuit <NUM> is configured to be able to detect a two-terminal portable electronic device <NUM> with an internal impedance <NUM> of up to about <NUM> kilo-ohms.

At block <NUM>, the method <NUM> includes comparing a potential difference across the internal impedance <NUM> to a reference voltage. In some embodiments, the device detection circuit <NUM>, via the universal serial bus type-C connector <NUM>, is configured to power down into an idle state when the two-terminal portable electronic device <NUM> is removed from the charging pocket <NUM>.

The method <NUM> includes powering the universal serial bus configuration channel line activation circuit <NUM> when the potential difference across the internal impedance <NUM> is greater than the reference voltage. In some embodiments, the method <NUM> includes electrically coupling the two-terminal portable electronic device <NUM> to the multi-pin universal serial bus connector when receiving, with a configuration channel pin <NUM>, an input from the universal serial bus configuration channel line activation circuit <NUM>. In some embodiments, the device detection circuit <NUM> is configured to accept an external power supply from an alternating current adapter with a universal serial bus type-C downstream port to power the detection circuit and charge a two-terminal portable electronic device <NUM>.

At block <NUM>, the method <NUM> includes charging, with the activation circuit (for example, the universal serial bus configuration channel line activation circuit <NUM>), the two-terminal portable electronic device <NUM> using a configuration channel pin (for example, configuration channel pin <NUM>) of the universal serial bus type-C connector <NUM> upon detection of the two-terminal portable electronic device <NUM>. In some embodiments, the method <NUM> includes automatically switching between a detection mode and a charging mode when the two-terminal portable electronic device <NUM> is detected as being placed in the charging pocket <NUM>. In some embodiments, the device detection circuit <NUM> is configured to alternate between a detection circuit to provide charging after detection of a two-terminal portable electronic device <NUM> and a linear regulator to provide low idle power consumption.

One advantage of the systems and methods provided herein is that the charger <NUM> can be kept powered down within a tight margin when a two-terminal portable electronic device <NUM> is not placed in the charging pocket <NUM>.

In the foregoing specification and accompanying drawings, one or more embodiments are described and illustrated. These embodiments are not limited to the specific details provided herein and may be modified in various ways. Furthermore, other embodiments may exist that are not described herein. Also, the functionality described herein as being performed by one component may be performed by multiple components in a distributed manner. Likewise, functionality performed by multiple components may be consolidated and performed by a single component. Similarly, a component described as performing particular functionality may also perform additional functionality not described herein. For example, a device or structure that is "configured" in a certain way is configured in at least that way, but may also be configured in ways that are not listed. Furthermore, some embodiments described herein may include one or more electronic processors configured to perform the described functionality by executing instructions stored in non-transitory, computer-readable media. Similarly, embodiments described herein may be implemented as non-transitory, computer-readable media storing instructions executable by one or more electronic processor to perform the described functionality.

Moreover in this document, relational terms such as first and second, top and bottom, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms "comprises," "comprising," "has," "having," "includes," "including," "contains," "containing" or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises, has, includes, contains a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by "comprises. a," "includes. a," or "contains. a" does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises, has, includes, contains the element. The terms "a" and "an" are defined as one or more unless explicitly stated otherwise herein. The terms "substantially," "essentially," "approximately," "about" or any other version thereof, are defined as being close to as understood by one of ordinary skill in the art, and in one non-limiting embodiment the term is defined to be within <NUM>%, in another embodiment within <NUM>%, in another embodiment within <NUM>% and in another embodiment within <NUM>%. The terms "connected" and "coupled" are used broadly and encompass both direct and indirect connecting and coupling. Further, "connected" and "coupled" are not restricted to physical or mechanical connections or couplings and can include electrical connections or couplings, whether direct or indirect. A device or structure that is "configured" in a certain way is configured in at least that way, but may also be configured in ways that are not listed.

Claim 1:
A method of charging a two-terminal portable electronic device (<NUM>) including a positive terminal (<NUM>) and a negative terminal (<NUM>), the method comprising:
detecting, with a detection circuit (<NUM>) having a charging pocket, the two-terminal portable electronic device and electrically coupling the positive terminal and the negative terminal of the two-terminal portable electronic device to a multi-pin universal serial bus connector (<NUM>) when the positive terminal (<NUM>) and the negative terminal (<NUM>) of the two-terminal portable electronic device are coupled to said charging pocket, the detection circuit (<NUM>) being coupled to a charger through the multi-pin universal serial bus connector (<NUM>);
characterized by
detecting an internal impedance across the positive and negative terminal of the two terminal portable electronic device;
comparing a potential difference across the internal impedance with a reference voltage;
powering an activation circuit when the potential difference across the internal impedance is greater than the reference voltage; and
initiating charging, with the activation circuit, of the two-terminal portable electronic device (<NUM>) by the charger via the positive terminal and the negative terminal by using a configuration channel pin of the multi-pin universal serial bus connector (<NUM>) to set a voltage on the configuration channel pin of the multi-pin universal serial bus connector (<NUM>) upon said detection of the two-terminal portable electronic device.