A digital-to-analog converter is provided. The digital-to-analog converter includes a delay circuit configured to iteratively delay a digital input signal based on a clock signal for generating a plurality of delayed digital input signals. Further, the digital-to-analog converter includes a plurality of groups of inverter cells. Each group of inverter cells is configured to generate a respective analog signal based on one of the plurality of delayed digital input signals. The inverter cells includes a respective inverter circuit configured to invert the respective delayed digital input signal. The plurality of groups of inverter cells include different numbers of inverter cells. The digital-to-analog converter additionally includes an output configured to output an analog output signal based on the analog signals of the plurality of groups of inverter cells.

A digital-to-analog converter includes an amplifier, a voltage relaxation circuit, a base current source, a first weighting current source, and at least one second weighting current source. The amplifier receives a reference voltage and a feedback voltage, and generates an output voltage according to the reference voltage and the feedback voltage. The base current source is coupled to an output end of the amplifier through the voltage relaxation circuit, and is configured to generate an adjustable base current. The first weighting current source generates an adjustable first weighting current between a reference ground end and one of a current load and the voltage relaxation circuit according to a first bit of input data. The second weighting current source generates at least one second weighting current according to at least one second bit of the input data.

This application discusses techniques for reducing the energy of an output ripple in a voltage converter at a switching frequency of the voltage converter. In certain examples, an amplitude of a reference voltage can be modulated with a time-varying random value or pseudo-random value to provide a reduction in the energy of the output ripple at the switching frequency of the voltage converter.

A semiconductor device that can perform voltage monitoring with a small circuit area is provided. The resistive subdivision circuit RDIV performs the resistive subdivision of the input voltage Vin by means of the input ladder resistor (R1-R4), and drives the nMOS transistors MN1-MN3 by the subdivided input voltages Vi1-Vi3 each having different resistive subdivision ratios, respectively. The pMOS transistor MP0 is provided in common for the pMOS transistors MP1-MP3, and configures a current mirror circuit with each of the pMOS transistors MP1-MP3. The bias current generating circuit IBSG supplies a bias current to the pMOS transistor MP1.

A reference voltage generator is disclosed that may provide a plurality of reference voltages. A reference voltage generator may include a voltage divider, a multiplexer coupled to the voltage divider, an operational amplifier that may receive a voltage from the multiplexer, and a plurality of resistors that may receive an output from the operational amplifier. The reference voltages may be provided from output terminals coupled to the resistors. A reference voltage generator may include a voltage divider, two multiplexers coupled to the voltage divider, an operational amplifier coupled to each multiplexer, and a plurality of resistors coupled between the outputs of the two operational amplifiers. Reference voltages may be provided from output terminals coupled to the resistors.

A low power voltage regulator includes a weighted transistor array having a plurality of transistor switches with a total conductance of G, corresponding to bits from a MSB to LSB. A transistor switch corresponding to the MSB has a conductance of G/2 and remaining bits have a consecutive descending conductance of G/2.sup.N to the LSB, and search time takes a low number of cycles by starting with the MSB. A redundant LSB transistor switch has the same G/2.sup.N conductance of the LSB. The redundant LSB is used to correct steady-state errors, and a proportional derivative controller compensates output voltage. The compensation in a method eliminates an output pole of the voltage regulator to provide a stable voltage regulator operation irrespective of load current, load capacitance, or sampling frequency. Voltage can be regulated via the additional LSB below the resolution limit via pulse width modulation.

A reference voltage generator is disclosed that may provide a plurality of reference voltages. A reference voltage generator may include a voltage divider, a multiplexer coupled to the voltage divider, an operational amplifier that may receive a voltage from the multiplexer, and a plurality of resistors that may receive an output from the operational amplifier. The reference voltages may be provided from output terminals coupled to the resistors. A reference voltage generator may include a voltage divider, two multiplexers coupled to the voltage divider, an operational amplifier coupled to each multiplexer, and a plurality of resistors coupled between the outputs of the two operational amplifiers. Reference voltages may be provided from output terminals coupled to the resistors.

A reference voltage generator is disclosed that may provide a plurality of reference voltages. A reference voltage generator may include a voltage divider, a multiplexer coupled to the voltage divider, an operational amplifier that may receive a voltage from the multiplexer, and a plurality of resistors that may receive an output from the operational amplifier. The reference voltages may be provided from output terminals coupled to the resistors. A reference voltage generator may include a voltage divider, two multiplexers coupled to the voltage divider, an operational amplifier coupled to each multiplexer, and a plurality of resistors coupled between the outputs of the two operational amplifiers. Reference voltages may be provided from output terminals coupled to the resistors.

Embodiments of the disclosure can provide digital-to-analog converter (DAC) termination circuits. A single or multiple parallel impedance networks can be coupled to a DAC to reduce the DAC's AC impedance, increase the DAC speed, and reduce the DAC settling time. The parallel impedance networks can be coupled to one or more of the DAC terminals in termination specific cases, or to nodes within the DAC. In an example, one-sided T-termination can be used with a single termination impedance path coupled in parallel with the DAC terminals, for reducing AC impedance at the DAC reference terminals, increasing speed, and reducing settling time. In an example, multiple impedance networks can be used in an H-bridge termination solution, which can be useful for high resolution DACs with or within a high voltage range.

A constant impedance switch dynamically manages switch impedance to eliminate or substantially reduce impedance glitches during switching events by stepping variable impedances through sequences of impedance values. As a result, VSWR may be reduced to or near 1:1, allowing programming and circuitry to be simplified. Switch impedance may be maintained for single and multi-throw switches having variable impedances of any order. Each variable impedance may comprise one or more configurable cells, subcells and elements controlled by thermometer, binary, hybrid or other coding technique.