Abstract: An integrated circuit comprises a host interface control block for providing a connection between the integrated circuit and a master controller device. The integrated circuit further includes a plurality of I/O pins. A capacitive touch sense circuitry enables detection of actuation of at least one capacitor switch of a capacitive sensor array connected to at least a portion of the plurality of I/O pins. An LCD controller drives at least one LCD connected to at least a portion of the plurality of I/O pins. The integrated circuit, responsive to signals received from the master controller device over the host interface control block, may be configured to monitor outputs from the capacitive sensor array in a first mode of operation. In a second mode of operation, the capacitive sensor array may be configured to drive at least one LCD. Finally, in a third mode of operation, the integrated circuit may be configured to both monitor outputs of the capacitive sensor array and drive the at least one LCD.

Abstract: A capacitive touch sensor circuitry comprises an interface for interconnecting with a plurality of I/O pins that connect to rows and columns of a capacitive sensor array. Monitoring circuitry, responsive to inputs from the plurality of I/O pins, determines when a capacitive switch in the capacitive sensor array has been actuated and stores an indication of the actuation of the capacitive switch. The monitoring circuitry then generates an interrupt responsive to the determined actuation. A control engine controls a manner in which the monitoring circuitry monitors the plurality of I/O pins. The control engine and the monitoring circuitry may be configured to monitor the plurality of I/O pins in a plurality of operating modes.

Abstract: A system and method for providing a tunable GMC filter is disclosed wherein a transconducted element having an attenuator in a feedback loop therewith is allowed to oscillate at a first oscillation frequency. An input to the filter enables tuning of the oscillation frequency to a pre-determined frequency.

Abstract: The present invention comprises a microcontroller unit including a processor for generating a power down signal. Control logic generates a hold signal responsive to the power down signal. A voltage regulator provides a regulated voltage responsive to an input voltage and powers down responsive to the power down signal. At least one digital device powered by the regulated voltage enters a powered down mode responsive to the voltage regulator entering the powered down state. The at least one digital device provides at least one digital output signal that is provided to an input/output cell. The input/output cell also is connected to receive a hold signal. The input/output cell maintains a last state of the digital output signal responsive to the hold signal when the at least one digital device enters the powered down state.

Abstract: A microcontroller unit includes a processor for generating a first control signal to start a comatose mode of operation for the microcontroller unit. Control logic responsive to the first control signal generates an enable signal at a first level and the control logic is further responsive to a second control signal for generating the enable signal at a second level. A voltage regulator generates regulated voltage from an input voltage. The voltage regulator shuts down to provide a zero volt regulated voltage responsive to the enable signal at the first level and powers up to provide a regulated voltage at an operating level responsive to the enable signal at the second level.

Abstract: A sampling network comprises analog comparator for comparing an analog voltage to a plurality of successive voltage inputs. A plurality of capacitors are connected in parallel with a first end of each of the capacitors coupled to the first input of the analog comparator to provide one of the successive voltage inputs. A first plurality of switches includes one switch associated with each of the plurality of capacitors to connect an input voltage to the second end of the capacitor. A bulk of a switch of the first plurality of switches is connected to the input voltage while the input voltage is being sampled and to a power supply voltage while the reference voltage is being sampled. A second plurality of switches is in parallel with the first plurality of switches and further includes one switch connected to each of the plurality of capacitors. The second plurality of switches connect a reference voltage to a second end of the capacitor.

Abstract: A system and method for providing a tunable GMC filter is disclosed wherein a transconducted element having an attenuator in a feedback loop therewith is allowed to oscillate at a first oscillation frequency. An input to the filter enables tuning of the oscillation frequency to a pre-determined frequency.

Abstract: An attenuator includes a first stage 601a having a first operational amplifier 602a and a tapped resistor 603a. Tapped resistor 603a has an input for receiving input data, an output coupled to an output of first operational amplifier 602a, and a plurality of taps for selectively presenting a sequence of voltages to a noninverting input of first operational amplifier 602a. Each of these sequences of voltages corresponds to an attenuation step such that first stage 601a steps the attenuation produced by the attenuator from an intermediate value to a predetermined ending value. A second stage 601b includes a second operational amplifier 602b and a tapped resistor 603b. Tapped resistor 603b includes an input for receiving analog data from first stage 601a, an output coupled to an output of second operational amplifier 602b, and a plurality of taps for selectively presenting a sequence of voltages to a noninverting input of operational amplifier 602b.

Abstract: Audio data processing circuitry 300 includes a plurality of analog inputs 101 for receiving analog audio data and a digital input 105 for receiving digital audio data. A analog mixer 312 mixes analog data received at said plurality of analog inputs 101 to generate a mixed analog audio stream. An analog-to-digital converter 313 converts the mixed analog audio stream to a digital audio stream and a digital mixer 315 mixes digital data received at the digital input 105 with the digital audio stream from the analog mixer 312 to generate a mixed digital audio stream.