Class / Patent application number | Description | Number of patent applications / Date published |
341154000 | Using ladder network | 26 |
20090128387 | FOLDED R-2R LADDER CURRENT-STEERING DIGITAL TO ANALOG CONVERTER - A folded R-2R ladder current-steering digital-to-analog converter is disclosed. In the folded R-2R ladder current-steering digital-to-analog converter, each node in the R-2R ladder is electrically coupled with a plurality of current sources with different weights. Therefore, the numbers of the resisters and current sources can be reduced, and efficient power saving and the high-speed operation can be achieved. | 05-21-2009 |
20090146856 | DIGITAL-TO-ANALOG CONVERTER WITH R-2R LADDER NETWORK BY POLARITY CONTROL - The present invention provides the voltage generator comprises providing a binary weight digital-to-analog converter (DAC) including an R-2R ladder network, and control switches, and an operation amplifier (OP) with a feedback resistance, and providing a plurality of voltages, from an input of said ladder network, in a positive polarity and a negative polarity, wherein said positive polarity and negative polarity are determined by a reference voltage, and each of said switches is switched between a connection to said OP and said reference voltage. | 06-11-2009 |
20090160690 | D/A CONVERTER CIRCUIT, INTEGRATED CIRCUIT DEVICE, AND ELECTRONIC APPARATUS - A D/A converter circuit which converts a digital signal of n bits into an analog signal and outputs the analog signal comprises: a plurality of D/A conversion processors, each of which converting a digital signal into an analog signal, the digital signal being made by dividing the n-bit digital signal at least into two; a plurality of output resistance regulators coupled to outputs of the plurality of respective D/A conversion processors; and an output signal generator generating the analog signal that forms an output of the D/A converter circuit based on outputs of the plurality of output resistance regulators. At least one of the D/A conversion processors is configured as a resistor string type D/A converter circuit including: a resistor string circuit which has a plurality of serially-coupled resistors and a plurality of switches, one end of each of the plurality of switches being coupled to one of coupling points of the plurality of resistors, and other ends of the plurality of switches being coupled together to form an output end; and a decode circuit which decodes the digital signal and generates a control signal that controls ON/OFF of the plurality of switches included in the resistor string circuit. Each of the plurality of output resistance regulators includes a variable resistance circuit which changes a resistance value to be substantially equal to an output resistance value of the D/A conversion processor, in accordance with a change in the output resistance value of the D/A conversion processor that is coupled to another output resistance regulator and configured as the resistor string type D/A converter circuit. | 06-25-2009 |
20090160691 | Digital to Analog Converter Having Fastpaths - A resistor-based digital to analog converter (DAC) having mux fastpaths, which selectively connect a subset (or an entirety) of voltage divider nodes in a DAC to either a higher level of multiplexor hierarchy, or a DAC output node, effectively bypassing one or more levels of multiplexor devices. In addition, the fastpaths may selectively connect lower levels of multiplexor hierarchy to higher levels of multiplexor hierarchy and/or a DAC output node. | 06-25-2009 |
20090184856 | DIGITAL-TO-ANALOG CONVERTER - A converter of 6-bit input includes a reference voltage generating circuit generating 17 reference voltages, a first switch circuit having 19 switch pairs each including MOS transistors for selecting two adjacent reference voltages in accordance with the four most significant bits, a second switch circuit including a series circuit of MOS transistors for dividing the selected two reference voltages into four to obtain three intermediate voltages, and a third switch circuit for selectively outputting the lower of the selected two reference voltages or one of the three intermediate voltages. In a second mode in which a gray level having a smaller ON-resistance of a MOS transistor than that in the first mode is selected, the number of MOS transistors used in the first and second switch circuits for voltage division is increased. | 07-23-2009 |
20100039304 | DIGITAL TO ANALOG CONVERTER AND METHOD THEREOF - A digital to analog converter (DAC) has a plurality of transistor-resistor units connected in a string. Each of the transistor-resistor units of the DAC has a pair of transistors that are turned on/off by a pair of complementary control signals. Since the two transistors of each transistor-resistor unit are positioned symmetrically, an equivalent resistance would be determined precisely according to received digital codes, such that an output voltage of the DAC could be adjusted precisely based on the equivalent resistance. | 02-18-2010 |
20100052966 | DIFFERENTIAL AMPLIFIER AND DATA DRIVER EMPLOYING THE DIFFERENTIAL AMPLIFIER - Disclosed is a differential amplifier which includes first and second input terminals, an output terminal, first and second differential pairs, and first and second current sources for supplying currents to the first and second differential pairs. The first differential pair has first and second inputs of an input pair connected to the first input terminal and the output terminal, respectively. The second differential pair has first and second inputs of an input pair connected to the second input terminal the output terminal, respectively. The differential amplifier further includes a load circuit connected to output pairs of the first and second differential pairs for outputting a signal obtained on combining outputs of the first and second differential pairs from at least one of a pair of connection nodes between the output pairs of the first and second differential pairs and the load circuit, an amplifier stage supplied with at least one signal at a connection node of the output pairs of the first and second differential pairs and the load circuit to output a voltage at the output terminal, and a current control circuit controlling the first and second current sources for controlling the ratio of currents supplied to the first and second differential pairs. | 03-04-2010 |
20100141498 | DIGITAL-TO-ANALOG CONVERTER (DAC) AND AN ASSOCIATED METHOD - The digital-to-analog converter in accordance with the present invention comprises an R-2R transistor-only ladder converter and a digital controller. The controller connects to the R-2R transistor-only ladder converter and comprises at least one regulating transistor and at least one shifting transistor. The at least one regulating transistor has an aspect ratio of k | 06-10-2010 |
20110102227 | FINE RESISTANCE ADJUSTMENT FOR POLYSILICON - A resistor string digital to analog converter formed of polysilicon resistor segments to each of which is applied an electric field. The approach improves the overall accuracy. | 05-05-2011 |
20120133538 | RESISTOR DEVICES AND DIGITAL-TO-ANALOG CONVERTERS USING THE SAME - A digital-to-analog converter (DAC) includes: a plurality of first controllers and a plurality of resistor devices. The plurality of first controllers are configured to be selectively switched on according to a received digital signal to control an analog signal according to the received digital signal. The plurality of resistor devices are respectively connected to the plurality of first controllers. The plurality of resistor devices include non-volatile memory devices. | 05-31-2012 |
20120146828 | DIGITAL-TO-ANALOG CONVERTER WITH NON-UNIFORM RESOLUTION - A circuit includes a digital-to-analog converter with non-uniform resolution for converting a digital signal into an analog signal. The digital-to-analog converter includes high-resolution circuitry, reduced-resolution circuitry coupled to the high-resolution circuitry and a switch coupled to the high-resolution circuitry and to the reduced-resolution circuitry. The switch couples one of the high-resolution circuitry and the reduced-resolution circuitry to an output node. The circuit also includes a decoder coupled to the switch. The decoder receives the digital signal to control the switch. | 06-14-2012 |
20120200442 | PRECISION SUB-RADIX2 DAC WITH LINEARITY CALIBRATION - A system includes an N bit sub-binary radix digital-to-analog converter (DAC) that converts an m bit digital input signal to an analog output signal, where m and N are integers greater than or equal to 1 and N>m. A radix conversion module determines a code ratio, the code ratio being a ratio of a total number of available monotonic codes to 2 | 08-09-2012 |
20120326907 | D/A CONVERTER INCLUDING HIGHER-ORDER RESISTOR STRING - A resistor string digital-to-analog converter includes an input terminal receiving a digital input signal in digital code, an output terminal revealing an analog output signal in analog voltage, a first plurality of voltage-acquisition nodes including a first pair of nodes which is adjacent to each other, a first plurality of resistors being connected in series via the first plurality of voltage-acquisition nodes, a second pair of nodes revealing a pair of analog voltages, a high-order voltage-acquisition circuit providing conduction between a respective one of the first pair of nodes and a respective one of the second pair of nodes in accordance with the digital input signal, a low-order converter generating the analog output signal, which is obtained by interpolating one and the other of the pair of analog voltages in accordance with the digital input signal. | 12-27-2012 |
20130169462 | Apparatus and Method for Dynamically Dampening a Transient Step Response - A circuit has a digital to analog (DA) resistance ladder having an analog output; a capacitor coupled to the analog output; a first resistance coupled from the capacitor to ground; and a switch coupled to the capacitor in parallel to the resistor, wherein the switch, when closed, has a second resistance, and the first resistance is greater than the second resistance. | 07-04-2013 |
20130222169 | D/A CONVERTER - A digital-to-analog (D/A) converter includes D/A conversion circuits and an amplifier circuit coupled between the D/A conversion circuits. Each D/A conversion circuit includes an R-2R ladder type resistor network, first transistors coupled between the resistor network and a first wiring at a first voltage level, and second transistors coupled between the resistor network and a second wiring at a second voltage level. The sizes of the first transistors are set at a ratio of powers of 2. The sizes of second transistors are set at a ratio of powers of 2. The second transistors are respectively turned on and off complementarily to the first transistors according to the digital input signal. | 08-29-2013 |
20130293405 | SEGMENTED DIGITAL-TO-ANALOG CONVERTER HAVING WEIGHTED CURRENT SOURCES - A digital input to a digital-to-analog converter (DAC) is divided into a most significant portion and a lesser significant portion. At least one tap voltage generator generates a plurality of voltages, preferably using a resistor string. A decoder decodes at least one sub-word that forms the lesser significant portion to generate a corresponding at least one control signal. A switching unit accesses voltages generated by the at least one tap voltage generator in response to the at least one control signal. A scaled current generator generates a respective weighted current from each accessed voltage. An output stage combines all the weighted currents with a voltage that is an analog representation of the most significant portion of the digital input to generate an analog approximation of the entire digital input. | 11-07-2013 |
20130314263 | Digital-to-Analog-Converter with Resistor Ladder - A digital-to analog-converter (DAC) has a MSB resistor ladder with a plurality of series connected resistors, wherein the MSB resistor ladder is coupled between a first and second reference potential, a LSB resistor ladder with a plurality of series connected resistors, and a plurality of switching units for connecting one of the series connected resistors of the MSB resistor ladder with the LSB resistor ladder, wherein each switching unit has a first switch for connecting a first terminal of an associated MSB resistor with a first terminal of the LSB resistor ladder and a second switch for connecting a second terminal of the associated MSB resistor with a second terminal of the LSB resistor ladder and wherein each switch is configured form a resistor of similar value of the resistors of the LSB resistor ladder when switched on. | 11-28-2013 |
20130335248 | RESISTOR-2 RESISTOR (R-2R) DIGITAL-TO-ANALOG CONVERTER WITH PARTIAL RESISTOR NETWORK RECONFIGURATION - A resistor-2 resistor (R-2R) digital-to-analog converter with partial resistor network reconfiguration. A circuit includes a plurality of resistor stacks. The circuit also includes a plurality of separation resistors which separate each of the plurality of resistor stacks. The circuit further includes a first selection circuit connected to a first resistor stack of the plurality of resistor stacks and a plurality of selection circuits connected between the plurality of separation resistors. The circuit also includes a termination resistor stack connected to a drain of the first resistor stack. | 12-19-2013 |
20130335249 | RESISTOR-2 RESISTOR (R-2R) DIGITAL-TO-ANALOG CONVERTER WITH RESISTOR NETWORK REVERSAL - A resistor-2 resistor (R-2R) digital-to-analog converter with resistor network reversal and methods of use are disclosed. A circuit includes a plurality of resistor stacks and a plurality of separation resistors which separate the resistor stacks. The circuit further includes a plurality of selection devices connected to a respective one of the plurality of resistor stacks. The circuit also includes a first termination resistor stack connected to a drain of a first resistor stack of the plurality of resistor stacks and a second termination resistor stack connected to a drain of a last resistor stack of the plurality of resistor stacks. The circuit further includes a first switch connected to the drain of the first resistor stack of the plurality of resistor stacks and an output. The circuit also includes a second switch connected to the drain of the last resistor stack of the plurality of resistor stacks and the output. | 12-19-2013 |
20140132435 | STRING DAC CHARGE BOOST SYSTEM AND METHOD - Embodiments of the present invention may provide a string DAC with charge boosting. The string DAC may include multiple strings, such as an MSB DAC and an LSB DAC, for converting a digital word into a corresponding analog voltage. The string DAC may also include a charge boost system to couple a charge into or out of the DAC during a code transition, such as a MSB code transition. The string DAC may operate in a break-before-make connection technique where all relevant connections are substantially open-circuited before new connections are made. Therefore, the charge boost may shorten the settling time of impedance elements in the string DAC between code transitions and may substantially reduce (or eliminate) glitches. | 05-15-2014 |
20140210657 | D/A CONVERTER - A digital-to-analog (D/A) converter includes first resistors coupled in series, second resistors respectively coupled to the first resistors and each having a resistance twice as large as the resistance of the first resistor, and first switch circuits respectively coupled to the second resistors. Third resistors each have a resistance twice as large as the resistance of the first resistor. Second switch circuits each are coupled to the third resistors and a GND wire. A control circuit controls the first and second switch circuit in accordance with the digital input signals to set a state of a connection node to either one of a first voltage, a second voltage, and a high impedance. | 07-31-2014 |
20140253357 | LOW GLITCH-NOISE DAC - An N-bit digital-to-analog converter (DAC) includes N input stages each of which generates the same amount of current and includes a pair of similarly sized transistor switches responsive to differential bits. The 2 | 09-11-2014 |
20150295584 | SWITCHABLE SECONDARY PLAYBACK PATH - In accordance with embodiments of the present disclosure, a processing system may include a plurality of processing paths including a first processing path and a second processing path, a digital-to-analog stage output, and a controller. The first processing path may include a first digital-to-analog converter for converting the digital input signal into a first intermediate analog signal, the first digital-to-analog converter configured to operate in a high-power state and a low-power state. The second processing path may include a second digital-to-analog converter for converting a digital input signal into a second intermediate analog signal. The digital-to-analog stage output may be configured to generate an analog signal comprising a sum of the first intermediate analog signal and the second intermediate analog signal. The controller may be configured to operate the first digital-to-analog converter in the lower-power state when a magnitude of the digital input signal is below a threshold magnitude. | 10-15-2015 |
20160056834 | MULTI-LEVEL LADDER DAC WITH DUAL-SWITCH INTERCONNECT TO LADDER NODES - A multi-level DAC includes first and second level resistor ladders, and a dual-switch ladder interconnect reduces DNL at tap-point transitions between first-level ladder resistors. For each first level resistor N, the switch-interconnect network includes dual (first/second) switches connectable to a resistor-top node NT, and dual (third/fourth) switches selectively connectable to a resistor-bottom node NB. The first switch is operable to connect NT to a top tap switch operable to select NT as a top tap point, and the fourth interconnect switch is operable to connect NB to a bottom tap switch operable to select NB as a bottom tap point. The first and fourth switches are connected, forming an outer loop that includes top and bottom tap points. The second switch connects to a top second-level resistor RT, and the third switch connects to a bottom second-level resistor RB, forming an inner loop that includes the series-connected second-level resistors. | 02-25-2016 |
20160072519 | HYBRID DIGITAL-TO-ANALOG CONVERSION SYSTEM - A digital-to-analog conversion (DAC) circuit has a resistor ladder circuit controlled by high order bits and a resistor string circuit controlled by low order bits. The resistor ladder circuit includes a stem resistor and a branch resistor. The stem resistor has a stem resistance, and the branch resistor has a branch resistance that is substantially equal to two times of the stem resistance. The resistor string circuit includes a string current source, a string resistor, and a bridge resistor. The string current source is configured to generate a string current that is based on a ratio of a reference voltage divided by a predetermined resistance. The string resistor has a string resistance that corresponds to the predetermined resistance, and it is configured to selectively receive the string current based on a selection signal decoded from the low order bits. | 03-10-2016 |
20160173112 | SWITCHABLE SECONDARY PLAYBACK PATH | 06-16-2016 |