Abstract: Certain aspects of the present disclosure generally relate to circuitry and techniques for digital-to-analog conversion. One example system for digital-to-analog conversion generally includes a first digital-to-analog converter (DAC) having an input coupled to an input node of the system and a mixing-mode DAC having an input coupled to an input node of the system. The mixing-mode DAC may include a second DAC and a mixer, an output of the second DAC being coupled to an input of the mixer. The system may also include a combiner, wherein an output of the first DAC is coupled to a first input of the combiner, and wherein an output of the mixer is coupled to a second input of the combiner.

Abstract: A current digital-to-analog converter includes a binary current-generating section configured to generate a binary-weighted current based on a first set of control signals; a unary current-generating section configured to generate a unary-weighted current based on a second set of control signals; and a current combining circuit configured to add or subtract a reference current and a current generated by a current source of the unary current-generating section using the binary-weighted current.

Abstract: An interleaved digital-to-analog converter (DAC) system may include a first sub-DAC and a second sub-DAC and may be configured to provide both a converter output signal and a calibration output signal. The converter output signal may be provided by adding the first sub-DAC output signal and the second sub-DAC output signal. The calibration output signal may be provided by subtracting one of the first and second sub-DAC output signals from the other. The calibration output signal may be used as feedback to adjust the phase of one of the sub-DACs relative to the other, to promote phase matching their output signals.

Abstract: Certain aspects of the present disclosure generally relate to a programmable multi-mode digital-to-analog converter (DAC) for generating a frequency-modulated signal. For example, certain aspects provide a circuit for sweeping a frequency of an output signal. The circuit generally includes a DAC having an input coupled to an input path of the circuit and an output coupled to an output path of the circuit, a first mixer selectively incorporated in the input path coupled to the input of the DAC, and a second mixer selectively incorporated in the output path coupled to the output of the DAC.

Abstract: Certain aspects of the present disclosure provide a digital-to-analog converter (DAC). The DAC generally includes a plurality of transistors selectively coupled to an output of the DAC, and a biasing circuit coupled to gates of the plurality of transistors. The biasing circuit may include a first transistor having a gate coupled to a drain of the first transistor, a first buffer having an input coupled to the gate of the first transistor, a second transistor having a gate coupled to an output of the first buffer, a first resistive-capacitive (RC) circuit having a first resistive element and a first capacitive element, the first RC circuit being coupled between the gate of the first transistor and the gate of the second transistor, and a first switch coupled between the first resistive element and the first capacitive element.

Abstract: A communication circuit may include a first pair of digital-to-analog converters (DACs) coupled to an input of a first mixer and configured to generate first baseband signals. The communication circuit may further include a second pair of DACs coupled to an input of a second mixer and configured to generate second baseband signals. The second baseband signals may be shifted in phase relative to the first baseband signals.

Abstract: A communication circuit may include a first pair of digital-to-analog converters (DACs) coupled to an input of a first mixer and configured to generate first baseband signals. The communication circuit may further include a second pair of DACs coupled to an input of a second mixer and configured to generate second baseband signals. The second baseband signals may be shifted in phase relative to the first baseband signals.

Abstract: A calibrating digital to analog converter (calDAC) architecture uses a low voltage memory to store the digital inputs of calDACs. The calDAC architecture includes a low voltage domain and a high voltage domain coupled to the low voltage domain. The low voltage domain includes a calDAC memory and a finite state machine (FSM). The high voltage domain includes a calDAC core, an interface circuit, and a bias control circuit coupled to the interface circuit. The interface circuit may be provided between the calDAC core and the low voltage domain. The bias control circuit is coupled to the interface circuit to generate a bias voltage for the interface circuit to drive switch transistors of the calDAC core.

Abstract: A calibrating digital to analog converter (calDAC) architecture uses a low voltage memory to store the digital inputs of calDACs. The calDAC architecture includes a low voltage domain and a high voltage domain coupled to the low voltage domain. The low voltage domain includes a calDAC memory and a finite state machine (FSM). The high voltage domain includes a calDAC core, an interface circuit, and a bias control circuit coupled to the interface circuit. The interface circuit may be provided between the calDAC core and the low voltage domain. The bias control circuit is coupled to the interface circuit to generate a bias voltage for the interface circuit to drive switch transistors of the calDAC core.

Abstract: In one embodiment, a method for converting an input digital signal into an analog signal is provided. The method comprises modulating the input digital signal into a modulated digital signal, and converting the modulated digital signal into the analog signal using a digital-to-analog converter (DAC). The modulation shapes quantization noise of the DAC to place a notch at a frequency within an out-of-bound frequency band to reduce the quantization noise within the out-of-bound frequency band.

Abstract: The present disclosure describes aspects of current removal for digital-to-analog converters (DACs). In some aspects, a circuit for converting a digital input to an analog output includes a first resistor ladder having first resistors connectable to respective current sources and connected to a first output of the circuit. The circuit also includes second resistor ladder having second resistors connectable to the respective current sources and connected to a second output of the circuit. A common node is formed between common resistor terminals of the first resistor ladder and the second resistor ladder. Current removal circuitry is connected to the common node and referenced to an amount of current provided by the respective current sources. By removing current from the common node of the resistor ladders, common-mode current at outputs of the circuit can be reduced with minimal degradation of differential performance of the circuit.

Abstract: Circuits and methods for compensating variation in an amplitude-regulated oscillator are provided. In one example, the oscillator includes a diode clamp having back-to-back diode-connected transistors with body terminals. Circuits and methods modulate a body-source voltage of the diode-connected transistors to compensate for process, temperature, and voltage variation.

Abstract: A reverse current protection (RCP) circuit is provided that includes an RCP switch coupled between a power supply rail and a buffer power supply node. A control circuit powered by a buffer supply voltage on the buffer power supply node controls the RCP switch to open in response to a discharge of a power supply voltage carried on the power supply rail.

Abstract: A converter including: an amplifier having first and second input terminals and an output terminal, the first input terminal configured to receive a reference voltage; an array of resistors configured to generate a tuning voltage; and a first plurality of switches coupled to the second input terminal of the amplifier and the array of resistors, the first plurality of switches configured to adjust a gain of the amplifier by selecting at least one resistor in the array of resistors to connect to the second input terminal of the amplifier.

Abstract: The present invention discloses an application attestation server and an application attestation method. Specially, there is provided an application attestation server that attests a certain application in a smart device, the application attestation server comprising: an executable code generation unit configured to generate executable codes for attestation with respect to the application; a transceiver configured to transmit an executable code randomly selected from the generated executable codes to the smart device, and receive a result of execution of the selected executable code with respect to the application from the smart device; a malicious application analysis unit configured to analyze whether the application is a malicious application based on the received result; and an analysis result providing unit configured to provide an analysis result of the malicious application analysis unit to a user.

Abstract: A method and apparatus are provided. The apparatus may be a capacitive element for adjusting a net capacitance of a circuit. The apparatus may be configured to be coupled to the circuit. The apparatus may be configured to adjust the net capacitance of the circuit to decouple common mode and differential loop bandwidth adjustment of the circuit. The capacitive element may include a pair of cross-coupled capacitors configured to be coupled to differential nodes of the circuit, and a pair of negative gain buffers coupled to respective capacitors.

Abstract: In one embodiment, a method for converting an input digital signal into an analog signal is provided. The method comprises modulating the input digital signal into a modulated digital signal, and converting the modulated digital signal into the analog signal using a digital-to-analog converter (DAC). The modulation shapes quantization noise of the DAC to place a notch at a frequency within an out-of-bound frequency band to reduce the quantization noise within the out-of-bound frequency band.

Abstract: A router is provided. The router includes a packet marking unit that inserts marking information generated based on an address of the router into a packet received by the router, according to a packet marking probability that is dynamically set, and a marking probability determination unit that calculates filtering efficiency of the router, and determines the packet marking probability based on the filtering efficiency. The marking information is used to obtain the address of the router by a device that has received the packet containing the marking information.

Abstract: A reverse current protection (RCP) circuit is provided that includes an RCP switch coupled between a power supply rail and a buffer power supply node. A control circuit powered by a buffer supply voltage on the buffer power supply node controls the RCP switch to open in response to a discharge of a power supply voltage carried on the power supply rail.

Abstract: A method and apparatus for attenuating transmit digital to analog converter (DAC) spurs is provided. The method begins when a reference voltage is injected into an amplifier. Next, an output of the ground low drop-out regulator is measured and is them compared with the reference voltage. The output of the amplifier is then adjusted based on the results of the comparison. If the reference voltage is higher then the output of the ground low drop-out regulator the output of the amplifier is adjusted to ground. If the reference voltage is lower than the output of the ground low drop-out regulator then the output of the amplifier is adjusted to match the reference voltage.