Abstract: An analog to digital converter (ADC) includes a cross switch array coupled between an input switch array and an integrator configured to alternately transfer charges from a first input capacitor and a second input capacitor to a first integration capacitor and a second integration capacitor thereby improving linearity problems caused by capacitor mismatching. The cross switch array may also be configured to transfer charges from the first input capacitor to the first integration capacitor and from the second input capacitor to the second integration capacitor during a first charge transfer time interval, and from the first input capacitor to the second integration capacitor and from the second input capacitor to the first integration capacitor during a second charge transfer time interval. A sensing system including and ADC consistent with the invention is also provided. Various methods of transferring charges in an ADC are also provided.

Abstract: A programmable after-package, on-chip reference voltage trim circuit for an integrated circuit having a plurality of programmable trim cells generating a programmed sequence. A converter is provided to convert the bit sequence into a trim current. The trim current is added to an initial value of a reference voltage to be trimmed, as generated by the integrated circuit. Once the correct value of the trim current is determined, isolation circuitry is programmed to isolate the trim circuitry from the remainder of the IC, thereby freeing the logic and package pins associated with the IC for use by users of the IC. The preferred trim circuitry includes fuses which are blown in accordance with a bit value supplied to the trim cell to permanently fix a trim current value, once a best fit value is determined.

Abstract: A lamp driving system that includes a first impedance and a second impedance coupled to the secondary side of a transformer, where the second impedance has a phase shifted value compared to the first impedance. Two lamp loads are connected in series together, and in parallel to the first and second impedances and to the transformer. The phase shift between the impedances ensures that the transformer need not supply double the striking voltage to strike the series-connected lamps. A difference in the resistance between the first and second impedances ensures that the lamps ignite in a specified sequence.

Abstract: A power management unit (PMU) apparatus and method may include: a bi-directional pin configured to serve as an input pin during a first condition and as an output pin during a second condition; or a battery charge controller for providing a first conditioning charge and a second full charge to a voltage source of the PMU; or an adapter detector configured to detect the presence of a continuous output adapter and a pulse output adapter; an under voltage lockout protection circuit to prevent start up of the PMU until a power source reaches a predetermined threshold lockout level and to shut down the PMU once the power source reaches a lower threshold lockout disabling level; or a plurality of internal switches for allowing an external switch to have multiple functions; or a power on reset circuit; or multi-output charge status pin.

Abstract: A sequential burst mode regulation system to deliver power to a plurality of loads. In the exemplary embodiments, the system of the present invention generates a plurality of phased pulse width modulated signals from a single pulse width modulated signal, where each of the phased signals regulates power to a respective load. Exemplary circuitry includes a PWM signal generator, and a phase delay array that receives a PWM signal and generates a plurality of phased PWM signals which are used to regulate power to respective loads. A frequency selector circuit can be provided that sets the frequency of the PWM signal using a fixed or variable frequency reference signal.

Abstract: An integrated controller for the detection and operation of both PC Cards, smart cards and passive smart card adapter cards. In one aspect, the invention detects the presence of standard expansion cards or passive smart card adapters by utilizing the reserved detection and voltage selection signal area defined by the PC Card specification. In another aspect, the invention provides an integrated controller that includes logic to operate either a standard expansion card or a passive smart card adapter by reassigning certain PC Card signal lines to operate a standard expansion card or a passive smart card adapter, thereby eliminating the need to provide pins in addition to those defined by the PC Card specification.

Abstract: A portable computer adapted with an application launch controller to selectively launch a desired application when the portable computer is in an off or suspended state. Programmable function keys are provided to permit users to define associated applications with the function keys to initiate launching of the application. The application launch controller includes bus interface circuitry to interface with system busses, for example, ISA bus and SMBus technology to exchange commands and data therewith. In the preferred embodiments, the application launch controller displays results of the desired application to an LCD display rather than the main system display to preserve power.

Abstract: A buffer battery power supply circuit is provided. In one embodiment, a battery charger circuit supplies a total output current which is delivered to both an active system and a battery. The total output current and the current delivered to a battery are sensed and compared to a preset threshold total output current signal and threshold battery current signal, respectively. The compared signals generate error signals which are provided as feedback to the battery charger circuit, so that the total output current can be controlled. In another embodiment, in addition to sensing the total output current and the battery current, the total output voltage is sensed and multiplied by the total output current, generating a total output power error signal. The error signals are provided as feedback to the battery charger circuit, so that the total output current and/or the total output voltage can be controlled.