Supercapacitor and charger for secondary power

A secondary power source system, includes a first unit receiving a primary power input and restricting a current used for charging to a predetermined amount, a second unit including a device providing capacitance, receiving a first output from the first unit with restricted current, a third unit generating a second output of a certain voltage, and a fourth unit performing a logical OR operation with the primary power input, first output from the first unit and second output from the second unit, to generate a single third output of a certain voltage.

FIELD OF THE INVENTION

The present invention relates generally to a power source. More particularly, the present invention relates to a secondary power source and charging for the secondary power source.

BACKGROUND OF THE INVENTION

Currently, when there is an interruption in the power supply to a vehicle or a device connected to the vehicle, many of the on-board devices of the vehicle or the circuitry in the device connected to the vehicle can be affected. This is especially important with regard to logic circuits or other memory type devices on a communication device that require an uninterrupted power supply in order to maintain either the data in the memory, the settings in the system, or power to accommodate communication between a computing device connected to the vehicle.

For example, when the primary power supply is reduced or shutoff, the settings and data in a memory can be lost, especially if it is a random access memory, which needs a constant power supply to maintain the settings and data. Therefore, when such an incident occurs, the memory unit loses all the information and the data has to be re-entered and the settings for the vehicle, or other information in the communication device, have to be reset.

Circuitry within a communication device accommodating connection between a diagnostic tool or a personal computer connected to a vehicle or the circuitry within the vehicle that draws power from the main power is then reliant on the main power. A backup power system can be added to a device, however, this then increases the cost and then there is a problem with the size and replacement of the backup power and the time it takes to charge the backup power. Further, if the device or circuits that needs the backup power is small, then it is difficult to provide such a backup power within the housing of the device or circuits.

Further, there is the issue of maintaining the proper power supply to the circuits and logic circuits as the power supply must be maintained at a certain level so that the logic circuits are not damaged. It is critical that the supply does not vary much from the parameters of the circuits, because the logic circuits are very sensitive to the power that is provided.

Interruption of the power supply can be catastrophic as there can be loss of data and even the malfunctioning of an electrical device, because the power has been interrupted, even if it is for a short period of time. As mentioned above, the loss of power can reset the device, which may cause problems if certain customized settings were used. Specifically, there can be major data loss, including data collected over a long period of time or a short period of time in random access memory, which can cause major delays and problems in rectifying the situation,

Accordingly, it is desirable to provide an electrical energy storage unit and charger as a secondary power to a device to minimize the power interruption.

SUMMARY OF THE INVENTION

The foregoing needs are met, to a great extent, by the present invention, wherein one aspect of an apparatus is provided that in some embodiments to provide an electrical energy storage unit and charger as a secondary power to a device.

In accordance with one embodiment of the present invention, a secondary power source system, including a first unit receiving a primary power input and restricting a current used for charging to a predetermined amount, a second unit comprising a device storing electrical energy, receiving a first output from the first unit with restricted current, a third unit generating a second output of a certain voltage, a fourth unit performing a logical OR operation with the primary power input, first output from the first unit and second output from the second unit, to generate a single third output of a certain voltage.

The device storing electrical energy can also be a capacitor. The device storing electrical energy can also be a super capacitor or ultra capacitor with a certain energy density. The first unit can includes a charging device receiving the primary power input and regulating the first power output. The charging device includes controlling the current. The device for storing electrical energy includes a plurality of capacitors in series.

The device storing electrical energy can include a plurality of super capacitors in series. The primary power source, first power output, second power output and third power output can be in a range between and including 3.3 volts to 5 volts. The first unit can include a charging device accommodating the restriction of current to the certain amount and includes thermal regulation. A logic circuit of a device can maintain a certain power in the third power output when the primary power source is reduced from a certain power.

In accordance with still another embodiment of the invention, a secondary power source system, includes a means for charging receiving a certain power input, a means for providing capacitance being charged by the means for charging, a means for a voltage regulator generating a certain voltage from the power input from the means for providing capacitance, and a means for selecting between the certain power input, output from the means for providing capacitance, and the output from the means for the voltage regulator.

An output from the means for selecting can be forwarded to a logic circuit of a device accommodating a providing of the secondary power source when the primary power source has been reduced. A logic circuit can receive a predetermined power from the means for selecting when a primary power source is reduced from a certain power. The means for providing capacitance can include a super capacitor. The means for providing capacitance can include a plurality of super capacitors in series.

The means for charging can include a charging device with thermal regulation. The means for charging restricts the current used for charging to a predetermined current. A voltage from the means for the voltage regulator can provide a voltage less than the certain power input of the means for charging. The secondary power source can provide the output power from the means for selecting operating online with a vehicle power source to all uninterrupted power source during a cold cranking incident.

The output from the means for selecting accommodating only a power to certain communication and memory operation of a unit can be powered by the secondary power source system.

In accordance with yet another embodiment of the invention, a method of providing a secondary power source, includes receiving a primary power input and restricting a current used for charging to a predetermined amount, receiving a first output from the first unit with restricted current and storing the power in a capacitance unit, generating a second output of a certain voltage, and performing a logical OR operation with the primary power input, first output from the first unit and second output from the second unit, to generate a single third output of a certain voltage.

The method can further include providing a device uninterrupted power supply from the single third output when there is a cold cranking incident with the vehicle. The capacitance unit can be a super capacitor or ultra capacitor with a certain energy density. The charging device can receive the primary power input and regulate the first power output. The charging device can include thermal regulation and current regulation.

DETAILED DESCRIPTION

The invention will now be described with reference to the drawing figures, in which like reference numerals refer to like parts throughout. An embodiment in accordance with the invention includes a secondary power supply that provides an uninterrupted power supply. The invention provides an electrical energy storage unit and charger that supply electrical energy as secondary power. The invention includes the use of capacitors including super capacitors that have to be charged.

Referring toFIG. 1, an example of a block diagram of the circuit of a secondary power unit10of the invention is shown. A current restriction section20feeds into a super capacitor section40, which then connects with a boost regulator section60, and finally the signal is outputted in the output section90of the secondary power unit10. In other embodiments, additional sections can be added or some of the sections mentioned above can be combined or removed.

The current restriction section20takes a 5VDC(volt direct current) rail36(shown inFIG. 2) and uses it to charge the supercapacitors of the supercapacitor section40. Other voltages can also be used, since 5 volts is only an example and is not meant to be limiting. One of the principle purposes of the current restriction section20is to restrict the amount of current used for charging to a current such as 200 mA (milli-amps) or a previously determined level. Other current levels can be used, but the current should be maintained at least at the predetermined level or within a certain variance from the predetermined level. The purpose of restricting the current is to maintain some level of safety during charging, otherwise the system will attempt to draw an excessive amount of current to immediately charge the super capacitors of the super capacitor section40. This massive inrush of power would potentially create sparking and could ignite flammable gases. Therefore, having the current restriction section helps in the safety and reliability of the secondary power unit10.

Referring toFIG. 2, the 5 volt rail36is fed into a linear charger26. The charger26can charge batteries such as lithium ion, nickel-metal hydride, and nickel cadmium or other power chargeable devices such as super capacitors42,44. The charger26can have thermal regulation capabilities to maintain stability in the system. The charger26can be a constant current and constant voltage linear charger and can work for example with USB (Universal Serial Bus) power specifications. An external resistor, MOSFET (metal-oxide semiconductor field effect transistor) or blocking diode is not required when using the charger26in the secondary power unit10. When the 5VDC rail36is removed, the charger can automatically enter into a low current state, dipping the battery current drain to less than the set current. When, however, the power is applied through the 5VDCrail36, the charger26can be placed into a mode where the supply current is at the set current. The power input for the charger26can include capacitance through a capacitor24at a node32between the charger26and the 5VDCrail36. The output to charge the battery (BAT)22is sent through a diode30, which restricts the direction of the flow of current away from the charger26and into the supercapacitor unit40.

The super capacitor section40contains the super capacitors42,44. The super capacitors42and44are placed serially to increase their voltage handling capability. Other configurations and quantity of super capacitors can also be used.

A super capacitor stores energy by physically separating positive and negative charges, whereas a battery will perform such an activity on a chemical basis. The interior materials have a high surface area, aiding in the high density of energy that can be stored.

The ultra capacitor can include a double-layer structure that polarizes an electrolytic solution to store energy electrostatically. Since there are no chemical reactions, the ultra capacitor is quick at charging and discharging like the supercapacitors42and44.

The supercapacitor42,44can be two non-reactive porous plates or collectors, suspended within an electrolyte with a voltage potential applied across the collectors. Once the super capacitor is charged, any device may use its energy. The energy density is much higher than ordinary capacitors.

The physical actions in the supercapacitor aid in the fast release of energy and the fast charging of the capacitor. The supercapacitors42and44can be placed in an RC circuit with resistors46and48, with the output going into the boost regulator section60.

The boost regulator section60is a boost regulator to generate, for example, 4.6VDC. Other voltages can be generated, depending on the application of the secondary power unit10. In this example, the 4.6 VDCvoltage was chosen so that the 5 VDCrail would be provided preferentially in the diode logic OR'ing node in the output section90.

The output from the super capacitor section40is sent through a LC circuit of the capacitor44and an inductor64, and the input is entered into a synchronous boost converter70. Schottkey diode68is also sent a signal from the inductor64and fed into the output node80, which also receives the output from the boost converter70. The boost converter70is a step-up DC/DC converter that operates from a certain input voltage. The boost converter70can include a MOSFET switch and synchronous rectifier, for example. The external Schottkey diode68is not required but included in the example. The output from the output node80is fed into the output section90.

The output section90, OR's together the three different potential voltage sources so a single 3.3VDCrail116can be generated. The rail116can be other voltages and the 3.3VDCis only shown as an example.

The output from the output node80is sent through the Schottkey diode92and outputted into node98. The 5VDCrail36and the bus voltage VBUS108, also meet at node98through Schottkey diode96. The 5VDC36, VBUS108, and the 4.6 VDCfrom the boost regulator section60are OR'd together to form a single 3.3 VDCoutput at node98. The output from the node98is sent to a low dropout regulator102which is capable of supplying a certain current with a certain low dropout voltage, thus providing a stable output.

Referring toFIGS. 2 and 3, the invention can limit the charge voltage and current to a specified level. The invention eliminates over-charging (which may cause damage) of the supercapacitors42,44, and open arching when connecting to a vehicle12. The invention is also used as a backup power source for any type of device, including, for example, a vehicle communication interface540that communicates between the vehicle12and a computing device, such as a diagnostic tool510, a personal computer410, or handheld computer, when the vehicle communication interface540is disconnected from the main power source of the vehicle. Also, data downloaded to the diagnostic tool510or personal computer410can be communicated despite a power loss.

Referring toFIGS. 3 and 4, for example, the vehicle12can provide the primary power to the vehicle communication interface540. The secondary power unit10can be, either integrated into the vehicle communication interface540as seen inFIG. 3, or outside of the vehicle communication interface, and connected electrically through a link18, as seen inFIG. 4. The secondary power circuit10, can be linked, either wirelessly, or through the wire by link16.

Further, the invention provides for regulated power to the device's core logic during reduced or removed voltage from a vehicle12. This has a distinct advantage over using a battery due to the significantly reduced amount of charging time and current as shown above.

The secondary power unit10provides for a unit, such as a diagnostic tool510or personal computer410, to communicate for at least a short period of time, independent of any other power source, with the vehicle12. This option is capable of operating the unit for a minimum of 5 seconds. In other embodiments, additional operating time is possible and part of the invention. The independent power source is able to operate on-line with the vehicle12power source to allow the unit, such as a vehicle communication interface540, an uninterrupted power source, for example, during a cold cranking incident.

Applicable communications with the host, such as a vehicle12connected to the unit, are to be maintained during a cold cranking incident. The blocks of circuitry that draw power from the 3.3V rail116can receive power during a cold cranking incident. This will allow the operation of, for example, RS232, USB (Universal Serial Bus) or the BLUETOOTH module in addition to a microcontroller such as an S12X, RAM (Random Access Memory), and Serial Flash, such as non-volatile memory, as seen inFIGS. 3 and 4with the secondary power unit10and the vehicle communication interface. The software will need to shutdown unused host communication interfaces when not needed, as this will maximize the duration of operation for the tool during a cold cranking incident, as the super-caps (supercapacitors)42and46will be used to support this functionality.

Referring toFIGS. 5 and 6, additionally, there can be an indicator signal labeled SUPCAP PWR570(connected to the processor524) which indicates that the communication to the diagnostic tool510is being powered from the super-caps (supercapacitors)42,44. The microcontroller524will then have to ensure that it is prepared for a complete loss. The indicator for supercapacitor power can also be located on the vehicle communication interface540itself, or on the personal computer410display820.

Referring toFIGS. 3 and 4, the secondary power unit10can be located in a plurality of different configurations as mentioned above. For example, as seen inFIG. 3, the secondary power unit10can be included in the vehicle communication interface540, which is connected between the vehicle12or device being tested and the diagnostic tool510or personal computer410.

Referring toFIG. 4, the secondary power unit10can be external to the vehicle communication interface540but connected to it, and the vehicle communication interface540or other communication interfaces are connected to a personal computer410, or alternatively, the diagnostic tool510.

FIGS. 5-6show the details of the diagnostic tool510ofFIG. 3. Manufacturers have programmed their vehicle onboard computers with complicated methods of detecting a variety of problems. Further, the United States Environmental Protection Agency has mandated that DTCs be set where there are emissions related problems with the vehicle using the Onboard Diagnostic II System, also known as the OBD II system.

However, there are still problems of using the diagnostic tool since there are limitations in troubleshooting the actual cause of the functional anomaly of the diagnostic tool. A user is forced to look directly at the diagnostic tool's limited display that may display only the DTC or simple indicator of function being performed, and a message indicating a communication failure.

In an embodiment of the invention, the diagnostic tool will run an application that accommodates the tool recording the cable used, the exact vehicle configuration that was entered, records communication transmissions and responses, hardware configuration, etc. If the user of the diagnostic tool is in case where the tool does not respond as anticipated, the user can indicate such information and communicate such information to a technical service line for interpretation. The information will then help determine if the user had incorrectly configured the tool for the vehicle (incorrect cable, wrong information entered, etc.). Automation of some or the entire process can also be performed.

FIG. 5is a front view illustrating a diagnostic tool510according to an embodiment of the invention. The diagnostic tool510can be any computing device, for example, the NEMISYS or GENISYS diagnostic tool from Service Solutions (part of the SPX Corporation) or other diagnostic tool. The diagnostic tool510includes a housing512to encase the various components of the diagnostic tool510, such as a display514, a user interface516, a power button518, a memory card reader520and a connector interface522. The display514can be any type display, including, for example, but not limited to, a liquid crystal display (LCD), organic light emitting diode (OLED), field emission display (FED), electroluminescent display (ELD), etc. In addition, the LCD, for example, can be touch screen that both displays and performs the additional task of interfacing between the user and the diagnostic tool510. The user interface516allows the user to interact with the diagnostic tool510, in order to operate the diagnostic tool as the user prefers. The user interface516can include function keys, arrow keys or any other type of keys that can manipulate the diagnostic tool510in order to operate the diagnostic tool through the software. The user interface or input device516can also be a mouse or any other suitable input device for the user interface516, including a keypad, touchpad, etc. The user interface516can also include keys correlating to numbers or alphanumeric characters. Moreover, as mentioned above, when the display514is touch sensitive, the display514can supplement or even substitute for the user interface516. The power key or button518allows the user to turn the power to the diagnostic tool510on and off, as required.

A memory card reader520can be a single type card reader, such as, but not limited to, a compact flash card, floppy disk, memory stick, secure digital, flash memory or other type of memory. The memory card reader520can be a reader that reads more than one of the aforementioned memory such as a combination memory card reader. Additionally, the card reader520can also read any other computer readable medium, such as CD (compact disc), DVD (digital video or versatile disc), etc.

The connector interface522allows the diagnostic tool510to connect to an external device, such as, but not limited to, an ECU (electronic control unit) of a vehicle, a computing device, an external communication device (such as a modem), a network, etc. through a wired or wireless connection. Connector interface522can also include connections such as a USB (universal serial bus), FIREWIRE (Institute of Electrical and Electronics Engineers (IEEE) 1394), modem, RS232, RS48J, and other connections to communicate with external devices, such as a hard drive, USB drive, CD player, DVD player, or other computer readable medium devices.

FIG. 6is a block diagram of the components of a diagnostic tool510. InFIG. 2, the diagnostic tool10, according to an embodiment of the invention, includes a processor524, a field programmable gate array (FPGA)526, a first system bus528, the display514, a complex programmable logic device (CPLD)530, the user interface516in the form of a keypad, a memory subsystem532, an internal non-volatile memory (NVM)534, a card reader536, a second system bus538, the connector interface522, and a selectable signal translator542. A vehicle communication interface540is in communication with the diagnostic tool510through connector interface522via an external cable. The connection between the vehicle communication interface540and the connector interface522can also be a wireless connection such as BLUETOOTH, infrared device, wireless fidelity (WiFi, e.g. 802.11), etc.

The selectable signal translator542communicates with the vehicle communication interface540through the connector interface522. The signal translator542conditions signals received from a motor vehicle control unit through the vehicle communication interface540to a conditioned signal compatible with the diagnostic tool510. The translator542can communicate with, for example, the communication protocols of J1850 signal, ISO 9141-2 signal, communication collision detection (CCD) (e.g., Chrysler collision detection), data communication links (DCL), serial communication interface (SCI), S/F codes, a solenoid drive, J 1708, RS232, controller area network (CAN), or other communication protocols that are implemented in a vehicle.

The circuitry to translate a particular communication protocol can be selected by the FPGA526(e.g., by tri-stating unused transceivers) or by providing a keying device that plugs into the connector interface522that is provided by diagnostic tool510to connect diagnostic tool510to vehicle communication interface540. Translator542is also coupled to FPGA526and the card reader536via the first system bus528. FPGA526transmits to and receives signals (i.e., messages) from the motor vehicle control unit through the translator542.

FPGA526is coupled to the processor524through various address, data and control lines by the second system bus538. FPGA526is also coupled to the card reader536through the first system bus528. Processor524is also coupled to the display514in order to output the desired information to the user. The processor524communicates with the CPLD530through the second system bus538. Additionally, the processor524is programmed to receive input from the user through the user interface516via the CPLD530. The CPLD530provides logic for decoding various inputs from the user of diagnostic tool510and also provides the glue-logic for various other interfacing tasks.

Memory subsystem532and internal non-volatile memory534are coupled to the second system bus538, which allows for communication with the processor524and FPGA526. Memory subsystem532can include an application dependent amount of dynamic random access memory (DRAM), a hard drive, and/or read only memory (ROM). Software to run the diagnostic tool510can be stored in the memory subsystem532. The internal non-volatile memory534can be, but not limited to, an electrically erasable programmable read-only memory (EEPROM), flash ROM, or other similar memory. The internal non-volatile memory534can provide, for example, storage for boot code, self-diagnostics, various drivers and space for FPGA images, if desired. If less than all of the modules are implemented in FPGA526, the non-volatile memory534can contain downloadable images so that FPGA526can be reconfigured for a different group of communication protocols.

Referring toFIG. 7, an example of a computer410, but not limited to this example of the computer410, that can read computer readable media that includes computer-executable instructions of the invention. The computer410includes a processor802that uses the system memory804and a computer readable memory device806that includes certain computer readable recording media. A system bus connects the processor802to a network interface808, modem812or other interface that accommodates a connection to another computer or network such as the Internet. The system bus may also include an input and output (I/O) interface810that accommodate connection to a variety of other devices. Furthermore, the computer410can output through, for example, the I/O810, data for display on a display device820.

The invention or parts thereof, can be realized as computer-executable instructions in computer-readable media. The computer-readable media includes all possible kinds of media in which computer-readable data is stored or included or can include any type of data that can be read by a computer or a processing unit. The computer-readable media include for example and not limited to storing media, such as magnetic storing media (e.g., ROMs, floppy disks, hard disk, and the like), optical reading media (e.g., CD-ROMs (compact disc-read-only memory), DVDs (digital versatile discs), re-writable versions of the optical discs, and the like), hybrid magnetic optical disks, organic disks, system memory (read-only memory, random access memory), non-volatile memory such as flash memory or any other volatile or non-volatile memory, other semiconductor media, electronic media, electromagnetic media, infrared, and other communication media such as carrier waves (e.g., transmission via the Internet or another computer). Communication media generally embodies computer-readable instructions, data structures, program modules or other data in a modulated signal such as the carrier waves or other transportable mechanism including any information delivery media. Computer-readable media such as communication media may include wireless media such as radio frequency, infrared microwaves, and wired media such as a wired network. Also, the computer-readable media can store and execute computer-readable codes that are distributed in computers connected via a network. The computer readable medium also includes cooperating or interconnected computer readable media that are in the processing system or are distributed among multiple processing systems that may be local or remote to the processing system. The invention can include the computer-readable medium having stored thereon a data structure including a plurality of fields containing data representing the techniques of the invention.