Abstract: A protection circuit for a battery pack, comprising: a thermistor for indicating a temperature of a cell in the battery pack; a first comparator coupled to the thermistor for determining whether the temperature has exceeded a charge cut-off temperature threshold for the cell, and if so, for turning off a first switch in series with the cell to prevent charging of the cell; and, a second comparator coupled to the thermistor for determining whether the temperature has exceeded a discharge cut-off temperature threshold for the cell, and if so, for turning off a second switch in series with the cell to prevent discharging of the cell.

Abstract: A handheld electronic device that includes a first battery and a holster that includes a second battery and a charging apparatus. When the handheld electronic device and the holster are electrically connected together, the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holster when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged. The holster further includes a microcontroller that communicates with a microprocessor on the handheld electronic device to identify alerts and activate a notification device powered by the second battery on the holster.

Abstract: A handheld electronic device in conjunction with a holder for the handheld electronic device that together form an electronic device. The handheld electronic device includes a first battery and the holder includes a second battery and a charging apparatus. When the handheld electronic device and the holder are electrically connected together, such as when the handheld electronic device is received in a cavity formed in the holder the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holder when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged.

Abstract: A protection circuit for a battery pack, comprising: a thermistor for indicating a temperature of a cell in the battery pack; a first comparator coupled to the thermistor for determining whether the temperature has exceeded a charge cut-off temperature threshold for the cell, and if so, for turning off a first switch in series with the cell to prevent: charging of the cell; and, a second comparator coupled to the thermistor for determining whether the temperature has exceeded a discharge cut-off temperature threshold for the cell, and if so, for turning off a second switch in series with the cell to prevent discharging of the cell.

Abstract: An improved handheld electronic device having a virtual navigational input device includes a case, and further includes an input apparatus and a processor apparatus disposed on the case. The processor apparatus executes a routine that compares vibrational results of a contact by a user on the case with reference vibrational results to identify the nature of the contact and to interpret the contact as an input to the processor. The exemplary contact with the case is in the nature of a sliding contact over a series of first features or over a series of second features and can be interpreted as one of more navigational inputs to the processor. The exemplary contact can also be in the nature of a touching or tapping contact or other contact with the case.

Abstract: A mobile communication device having a keyboard with a set of keys representing alpha-numeric characters, the keyboard comprising a light source, located within said mobile communication device; for providing a light; a set of sensors, associated with said keys, for sensing an amount of said light in a vicinity of each of said set of sensors, to determine which of said set of keys has been selected; and a transparent flat cover, overlying said set of sensors, displaying said set of alpha-numeric characters, for associating said set of alpha-numeric characters with said set of sensors.

Abstract: A mobile communication device having a keyboard with a set of keys representing alpha-numeric characters, the keyboard comprising a light source, located within said mobile communication device; for providing a light; a set of sensors, associated with said keys, for sensing an amount of said light in a vicinity of each of said set of sensors, to determine which of said set of keys has been selected; and a transparent flat cover, overlying said set of sensors, displaying said set of alpha-numeric characters, for associating said set of alpha-numeric characters with said set of sensors.

Abstract: A handheld electronic device in conjunction with a holder for the handheld electronic device that together form an electronic device. The handheld electronic device includes a first battery and the holder includes a second battery and a charging apparatus. When the handheld electronic device and the holder are electrically connected together, such as when the handheld electronic device is received in a cavity formed in the holder the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holder when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged.

Abstract: A handheld electronic device in conjunction with a holder for the handheld electronic device that together form an electronic device. The handheld electronic device includes a first battery and the holder includes a second battery and a charging apparatus. When the handheld electronic device and the holder are electrically connected together, such as when the handheld electronic device is received in a cavity formed in the holder the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holder when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged.

Abstract: A handheld electronic device that includes a first battery and a holster that includes a second battery and a charging apparatus. When the handheld electronic device and the holster are electrically connected together, the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holster when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged. The holster further includes a microcontroller that communicates with a microprocessor on the handheld electronic device to identify alerts and activate a notification device powered by the second battery on the holster.

Abstract: An electronic device and method of correcting keystroke errors in which a sequence of characters entered by actuating text character keys on a keyboard is checked against at least one database to determine if there is at least one word in the at least one database that begins with the sequence of words. Where no such words are found in the at least one database, a table of text character key locations is accessed to locate text character keys adjacent to each of the text character keys actuated to enter the sequence of characters, and one at a time, each character of the sequence of characters is substituted with a character corresponding to a text character key found to be adjacent to the text character key corresponding to the substituted characters, thereby creating one or more alternate sequences of characters.

Abstract: A handheld electronic device in conjunction with a holder for the handheld electronic device that together form an electronic device. The handheld electronic device includes a first battery and the holder includes a second battery and a charging apparatus. When the handheld electronic device and the holder are electrically connected together, such as when the handheld electronic device is received in a cavity formed in the holder the charging apparatus charges the first battery on the handheld electronic device from the second battery on the holder when the first battery charge has been depleted to a given level and the second battery charge is above a second given level. Alternatively, if the first battery charge is above a third given level the first battery charges the second battery if the second battery is not fully charged.

Abstract: A protection circuit for a battery pack, comprising: a thermistor for indicating a temperature of a cell in the battery pack; a first comparator coupled to the thermistor for determining whether the temperature has exceeded a charge cut-off temperature threshold for the cell, and if so, for turning off a first switch in series with the cell to prevent: charging of the cell; and, a second comparator coupled to the thermistor for determining whether the temperature has exceeded a discharge cut-off temperature threshold for the cell, and if so, for turning off a second switch in series with the cell to prevent discharging of the cell.

Abstract: A convenient source of charging power for portable communication devices is an integral power node of a computer data bus, such as a USB (universal serial bus) port. Unfortunately, USB ports have limited power capacity, making them generally incompatible with battery charge controllers (BCCs) which are designed to receive a steady, high capacity input. The invention provides a battery charging circuit which adjusts to the parameters of an external power supply such as a USB port by adding a regulating circuit to a standard BCC design. This regulating circuit maximizes the current drawn by the BCC, while keeping the voltage to the BCC above a preset minimum (the low voltage shut off level for the BCC). If the voltage to the BCC begins to drop, the regulating circuit reduces the current drawn, so the voltage rises and stays within the operating range of the BCC.

Abstract: A convenient source of charging power for portable communication devices is an integral power node of a computer data bus, such as a USB (universal serial bus) port. Unfortunately, USB ports have limited power capacity, making them generally incompatible with battery charge controllers (BCCs) which are designed to receive a steady, high capacity input. The invention provides a battery charging circuit which adjusts to the parameters of an external power supply such as a USB port by adding a regulating circuit to a standard BCC design. This regulating circuit maximizes the current drawn by the BCC, while keeping the voltage to the BCC above a preset minimum (the low voltage shut off level for the BCC). If the voltage to the BCC begins to drop, the regulating circuit reduces the current drawn, so the voltage rises and stays within the operating range of the BCC.