Abstract: According to one aspect, a mixed-signal tuner for analog and digital TV reception incorporates a demodulator for analog TV, employing various features for resolving limitations of the analog circuitry and for achieving compatibility with various global TV standards. Such features, which may be present in one or more embodiments, include the use of a variable sample rate in all digital clocks for frequency planning, and use of a microcontroller (MCU) to control various circuitry of the tuner.

Abstract: Techniques are disclosed relating to video signal-to-noise ratio (VSNR) measurement. In one embodiment, an analog television signal receiver includes a measurement circuit configured to measure noise in a video signal over one or more intervals that correspond to a horizontal control signal of the video signal and a control unit configured to determine a VSNR based on the measurement. In another embodiment, a first noise calculation circuit is configured to determine first noise information from a video signal and a second noise calculation circuit is configured to determine second noise information from a video signal in a manner different from the first noise calculation circuit. A control unit may be configured to generate a VSNR based on one or both of the first noise information and the second noise information.

Abstract: According to one aspect, a mixed-signal tuner for analog and digital TV reception incorporates a demodulator for analog TV, employing various features for resolving limitations of the analog circuitry and for achieving compatibility with various global TV standards. Such features, which may be present in one or more embodiments, include the use of a variable sample rate in all digital clocks for frequency planning, and use of a microcontroller (MCU) to control various circuitry of the tuner.

Abstract: In various implementations, a re-configurable phase lock loop may have multiple signal paths, including a feedforward path to operate in a carrier frequency acquisition mode to obtain a carrier frequency estimate and a feedback loop path to operate in a carrier frequency tracking mode to translate an incoming signal to a baseband signal. The multiple signal paths may share most of the hardware to reduce implementation cost.

Abstract: In various implementations, a re-configurable phase lock loop may have multiple signal paths, including a feedforward path to operate in a carrier frequency acquisition mode to obtain a carrier frequency estimate and a feedback loop path to operate in a carrier frequency tracking mode to translate an incoming signal to a baseband signal. The multiple signal paths may share most of the hardware to reduce implementation cost.

Abstract: According to one aspect, a mixed-signal tuner for analog and digital TV reception incorporates a demodulator for analog TV, employing various features for resolving limitations of the analog circuitry and for achieving compatibility with various global TV standards. Such features, which may be present in one or more embodiments, include the use of a variable sample rate in all digital clocks for frequency planning, and use of a microcontroller (MCU) to control various circuitry of the tuner.

Abstract: According to one aspect, a mixed-signal tuner for analog and digital TV reception incorporates a demodulator for analog TV, employing various features for resolving limitations of the analog circuitry and for achieving compatibility with various global TV standards. Such features, which may be present in one or more embodiments, include the use of a variable sample rate in all digital clocks for frequency planning, and use of a microcontroller (MCU) to control various circuitry of the tuner.

Abstract: Programmable on-chip identification circuitry and associated method are disclosed that provide integrated circuits with the ability to select and report from multiple different vendor and system identification configurations. The integrated circuit device includes programmable circuitry that utilizes vendor identification, system identification, configuration or other device information provided or selected at least in part based upon selection information from a source external to the integrated circuit. The selection information may be provided through one or more externally generated digital and/or analog control signals that are then processed within the integrated circuit device to select, access and utilize desired identification information stored in an on-chip database.

Abstract: A reset circuit that incorporates a battery monitor and watchdog timer in an integrated circuit is disclosed. A battery monitor having an output indicative of a charge state of a battery and a watchdog timer having an output indicative of an operational state of software being executed by the integrated circuit are connected to reset logic having a reset signal output, wherein the reset logic generates a reset signal on the reset signal output if either the battery monitor output or the watchdog timer output is active.

Abstract: A digital cordless telecommunications unit that serves for communications when paired with a similar unit and connected with a network is disclosed. The unit receives analog receive voice signals and transmits analog transmit voice signals. In addition, the unit transmits digital baseband transmit signals and receives digital formatted baseband receive signals. The unit includes a baseband chip, as well as an audio functions circuit and a system control functions circuit. The audio functions circuit comprises an audio front end for receiving the analog receive voice signals and transmitting the analog transmit voice signals, and an adaptive differential pulse code modulator codec, connected to the audio front end, for converting the analog receive voice signals to the digital transmit signals and converting the digital formatted baseband receive signals to the analog transmit voice signals.

Abstract: A battery monitor with programmable voltage references. The battery monitor includes a comparator circuit connected to a battery for receiving a voltage level thereof and to a voltage reference circuit for receiving a at least one reference voltage generated thereby. A trim circuit is connected to the voltage reference circuit for adjusting the reference voltage(s) and generated by the voltage reference circuit. The comparator circuit compares the voltage level of the battery with the reference voltage(s) generates an output based on the relative value of the battery voltage compared to the reference voltage(s). The trim circuit is programmable and includes a microprocessor connected to a programmable register and a memory. The microprocessor obtains trim data from the memory and writes the trim data to the programmable register.

Abstract: A method for handling underflow and overflow of data in a FIFO buffer includes steps of inserting an insert data word in the FIFO buffer if there is an underflow of data at the FIFO buffer and discarding a discard data word of the FIFO buffer if there is an overflow of data at the FIFO buffer. In one embodiment, the insert data word is null and does not change the status of the FIFO buffer.

Abstract: A digital communications DQPSK passband detector having a matched filter, a differential decoder, and a slicer that use elementary circuit components. In the matched filter, recovered carrier reference signals are fed along with the received signal to a pair of XNOR gates. This arrangement effectively results in a multiplication operation without any complex circuit elements. The outputs of the XNOR gates control the direction of counting of a pair of binary counters that generate correlated values of the I and Q components in the received signal. Thus, the integrate/dump circuits of a conventional matched filter are replaced with simpler digital counters. A digital differential decoder to extract the phase difference information between two consecutive received symbols is built from a network of delay elements, multipliers, and adders to recover the phase data.

Abstract: A telephone for digital cordless telecommunications includes a frame formatter for logical channel formatting of transmitted baseband signals and received baseband signals. The telephone comprises a radio interface connection with the frame formatter, a FIFO/codec interface conductively coupled to the frame formatter, an interrupt interface conductively coupled to the frame formatter, a data control logic interface conductively coupled to the frame formatter, and a microcontroller interface conductively coupled to the frame formatter.

Abstract: A method for enabling communications between a first communications unit and a second communications unit. The first communications unit has a first crystal that provides first unit timing for that unit. The second communications unit has a second crystal that provides second unit timing for the second communications unit. The method includes the steps of receiving the first unit timing by the second communications unit, detecting a transition of a cycle of the first unit timing received, generating a reset pulse upon each detection of the transition of the cycle of the first timing unit received, and initiating a start-up of a new sequence of the second unit timing upon occurrence of the reset pulse. Operation according to the method allows for a wide variety of external protocols to be used with appropriate communications results.

Abstract: A keypad monitor implemented in an integrated circuit monitors the closure of a plurality of keypad switches coupled to input terminals of the integrated circuit. The keypad monitor is operative in a first mode for monitoring a first number of the input terminals and a second mode for monitoring a lesser number of input terminals. When in the second mode, the unmonitored input terminals are converted for a use not related to keypad monitoring.