Patent classifications
H03M1/808
Digital-to-analog converter (DAC)-based driver for optical modulators
A data driver includes pre-driver circuitry coupled to a digital-to-analog converter (DAC) via a plurality of bit lines. The pre-driver circuitry is configured to receive a plurality of first voltages corresponding to respective bits of a digital codeword. Each of the first voltages may have one of a first voltage value or a ground potential based on a value of the corresponding bit. The pre-driver circuitry is further configured to drive a plurality of second voltages onto the plurality of bit lines, respectively, by switchably coupling each of the bit lines to ground or a voltage rail based at least in part on the voltage values of the plurality of first voltages. The voltage rail provides a second voltage value that is greater than the first voltage value. The DAC converts the plurality of second voltages to an electrical signal which is an analog representation of the digital codeword.
Precision current-to-digital converter
A current sensing system and delta sigma modulator architecture are discloses for sensing and digitizing a current input signal from a high impedance signal source with improve power efficiency. The delta sigma modulator integrates a signal condition stage within the delta sigma modulator feedback loop by utilizing a capacitive summation stage. For given gain, resolution, and bandwidth requirements, the delta sigma modulator architecture achieves reduced power consumption by advantageously reducing the number of nodes in the system that require a high dynamic range. Additionally, the delta sigma modulator has very high input impedance such that the input of the delta-sigma modulator can be connected directly to a high impedance signal source, without the need for a front-end pre-amplifier stage, or the like.
Segmented resistor string type digital to analog converter and control system thereof
A segmented resistor string type digital to analog converter comprises: a most significant bit (MSB) resistor string (104) comprising a high level resistor string, an intermediate level resistor string and a ground level resistor string; a decoding circuit (101), configured to decode an n-bit code of the MSB resistor string (104) and output 2.sup.n decoded codes; a logic sequential generation circuit (102), connected to the decoding circuit (101) and configured to perform a logic operation on a middle-position code among the 2.sup.n decoded codes and a refresh clock signal in non-overlapping sequences, and output two groups of control signals with completely complementary high level durations; a control signal bootstrap circuit (103), connected to the logic sequential generation circuit (102) and configured to perform bootstrap processing on the control signal, and increase the high level of the control signal to a sum of a power supply voltage and a threshold voltage; and a first switch group (106), connected to the control signal bootstrap circuit (103) and the intermediate level resistor string, where on/off of the first switch group (106) is controlled by the control signal after the bootstrap processing, so as to connect the intermediate level resistor string to the circuit or disconnect the intermediate level resistor string from the circuit.
Method for compensating electrical device variabilities in configurable-output circuit and device
A method has been disclosed that relates to electrical variability compensation technique for configurable-output circuits. The compensation technique can be applied to a generality of circuits whose output has to vary between two electrical limits spanning the range in between them according to a specific code given as input. A switching sequence that is process gradient-direction agnostic has been disclosed which limits variability. An electric device comprising a processing gradient-direction agnostic configurable-output circuit has been also disclosed.
Digital-to-analog converter with digitally controlled trim
In described examples, a digital-to-analog converter (DAC) includes an output, a ground, a reference voltage terminal, an input code terminal, multiple switches, multiple resistors, and a controller. The switches couple to the reference voltage terminal when activated and to the ground when deactivated. The resistors are variously coupled between corresponding ones of the switches and the output, so that activating the switches causes the DAC to output an output voltage. The controller is coupled to the input code terminal and coupled to control the switches. The controller generates an output code based on an input code in response to at least one differential nonlinearity error greater than one least significant bit voltage. The input code corresponds to a first ideal output voltage, the output code corresponds to a second, different ideal output voltage. The controller generates an output voltage by controlling the switches using the output code.
Force sensing systems
The present disclosure relates to a compensation circuit for compensating for an offset voltage that is present in an output signal output by a force sensor. The compensation circuit comprises: voltage divider circuitry, the voltage divider circuitry configured to receive a bias voltage that is also supplied to the force sensor and to output a control voltage derived from the bias voltage, wherein a component mismatch ratio of the voltage divider circuitry is adjustable to correspond to a component mismatch ratio of the force sensor; current generator circuitry configured to receive the control voltage and to generate a compensating current based on the received control voltage; and amplifier circuitry configured to receive the differential signal output by the force sensor and the compensating current and to output a compensated differential output signal in which the offset voltage is at least partially cancelled.
AMPLIFIER WITH ADJUSTABLE HIGH-FREQUENCY GAIN USING VARACTOR DIODES
The detection matrix for an Orthogonal Differential Vector Signaling code is typically embodied as a transistor circuit with multiple active signal inputs. An alternative detection matrix approach uses passive resistor networks to sum at least some of the input terms before active detection.
SEGMENTED RESISTIVE DIGITAL TO ANALOG CONVERTER
A digital to analog converter (DAC) that receives a binary coded signal and generates an analog output signal includes a binary-to-thermometer decoder and a resistive network. The decoder receives the binary coded signal, and decodes it into thermometer signals. The resistive network has branches that are coupled to an output terminal of the DAC in response to the thermometer signals. Each of the branches includes first and second resistors, and a switch. The first resistor is coupled between a first reference voltage and the switch, and the second resistor is coupled between a second reference voltage and the switch. The switch couples either the first resistor or the second resistor to the output terminal in response to a corresponding thermometer signal.
Digital to Analog Converter Circuit and Operating Method Thereof
A digital to analog converter circuit applied to a source driving apparatus is disclosed. The digital to analog converter circuit includes P-type transistors coupled in series, N-type transistors coupled in series and a substrate voltage control unit. The substrate voltage control unit is coupled to substrates of the P-type transistors and substrates of the N-type transistors respectively and used for controlling the substrates of the P-type transistors to have a first substrate voltage and controlling the substrates of the N-type transistors to have a second substrate voltage. The first substrate voltage is an operating voltage substituted by a specific voltage difference and the second substrate voltage is a ground voltage added by the specific voltage difference, and the operating voltage is higher than the ground voltage.
DIGITAL-TO-ANALOG CONVERTERS WITH TRIODE SWITCHES
Current steering digital-to-analog converters (DACs) are described. These DACs are suitable for high speed operation. Weight transistors conventionally used in DACs are replaced with resistors, resulting in a lower RC constant. Further, the resistors cause a smaller voltage drop, thus improving the voltage headroom of the DAC. Additionally, the current steering switches are biased in the triode region, as opposed to the saturation region as in conventional designs. Biasing the switches in the triode region results in a smaller drain-source voltage, which further improves the voltage headroom of the DAC. The triode operation further results in a substantially smaller output impedance, which leads to the output voltage being dictated primarily by the output transistor of the current path. Lastly, reset switches are added which reduce data-dependent memory effects that can otherwise produce distortion.