Abstract: An amplifier including: an input terminal coupled to a first node; an output terminal coupled to a second node; and a transistor coupled between a first power source and a second power source, the transistor including: a gate electrode coupled to the first node; a drain electrode coupled to the second node; a source electrode coupled to a third node; and a bulk electrode coupled to a fourth node and configured to receive a bulk voltage to change a threshold voltage of the transistor.

Abstract: A circuit includes: a cascode current source comprising: a current mirror transistor; and a cascode transistor; and a bias circuit coupled to the cascode current source, the bias circuit comprising: a current source; a first transistor coupled in series to the current source to form a first current path through the current source and the first transistor; a second transistor coupled in series to the current source; and a third transistor coupled in series to the second transistor and the current source to form a second current path through the current source and the second and third transistors, wherein the third transistor has a channel size greater than a channel size of the second transistor by a multiple determined according to a design factor of the bias circuit.

Abstract: A current mode logic buffer includes a differential pair of input transistors comprising a first input transistor and a second input transistor, a first output load resistor coupled in series with the first input transistor, a second output load resistor coupled in series with the second input transistor, a first output at a first node between the first output load resistor and the first input transistor, a second output at a second node between the second output load resistor and the second input transistor, a first hold capacitor configured to provide a semi-constant voltage source to the first output via a first low-resistance path, and a second hold capacitor configured to provide a semi-constant voltage source to the second output via a second low-resistance path.

Abstract: A current mode logic buffer includes a differential pair of input transistors comprising a first input transistor and a second input transistor, a first output load resistor coupled in series with the first input transistor, a second output load resistor coupled in series with the second input transistor, a first output at a first node between the first output load resistor and the first input transistor, a second output at a second node between the second output load resistor and the second input transistor, a first hold capacitor configured to provide a semi-constant voltage source to the first output via a first low-resistance path, and a second hold capacitor configured to provide a semi-constant voltage source to the second output via a second low-resistance path.

Abstract: An amplifier including: an input terminal coupled to a first node; an output terminal coupled to a second node; and a transistor coupled between a first power source and a second power source, the transistor including: a gate electrode coupled to the first node; a drain electrode coupled to the second node; a source electrode coupled to a third node; and a bulk electrode coupled to a fourth node and configured to receive a bulk voltage to change a threshold voltage of the transistor.

Abstract: A bias circuit for biasing a field effect transistor (FET) to provide a transconductance (gm) that is substantially unaffected by power supply voltage variations. In one embodiment the circuit includes two parallel current paths, each including two amplifying elements such as FETs, the FETs in one of the paths both being diode-connected, and the FETs in the other path not being diode-connected. Variations in the power supply voltage result in comparable changes in the voltage drops across all four FETs, and drain-induced barrier lowering (DIBL) results in relatively small changes in gm with changes in power supply voltage.

Abstract: A system for forwarding a sample rate clock along with data. In one embodiment, a sample rate clock is sent by a transmitter, along with data, to one or more receivers. The receivers sample the received data using the received sampling clock. Delay adjust circuits in the transmitter adjust the delay of each transmitted data stream using delay error sensing and correction implemented in a back channel between the receivers and the transmitter.

Abstract: An impedance circuit coupled to a first power supply includes: an output node; a transistor coupled between the output node and the first power supply, wherein the transistor comprises a gate electrode; and a voltage source electrically coupled to the gate electrode of the transistor and configured to apply a gate voltage to the gate electrode of the transistor, wherein the voltage source includes: a plurality of impedance components electrically coupled in series between a circuit node and the first power supply, and a current source electrically coupled between the circuit node and a second power supply.

Abstract: A receiver for receiving digital data after transmission through a channel which produces inter-symbol interference or other distortion. In one embodiment, a received signal is differentiated before being digitized to form an output digital bit stream, to reduce the effects of inter-symbol interference and other distortion in the channel. The differentiated signal is compared to two threshold values, a first threshold value, and a second threshold value, the first threshold value being greater than the second threshold value. When the differentiated signal exceeds the first threshold, the output bit is 1, when the differentiated signal is less than the second threshold value, the output bit is 0, and when the differentiated signal is between the first threshold value and the second threshold value, the output bit is the same as the previous output bit.

Abstract: A circuit includes: a cascode current source comprising: a current mirror transistor; and a cascode transistor; and a bias circuit coupled to the cascode current source, the bias circuit comprising: a current source; a first transistor coupled in series to the current source to form a first current path through the current source and the first transistor; a second transistor coupled in series to the current source; and a third transistor coupled in series to the second transistor and the current source to form a second current path through the current source and the second and third transistors, wherein the third transistor has a channel size greater than a channel size of the second transistor by a multiple determined according to a design factor of the bias circuit.

Abstract: A bias circuit for biasing a field effect transistor (FET) to provide a transconductance (gm) that is substantially unaffected by power supply voltage variations. In one embodiment the circuit includes two parallel current paths, each including two amplifying elements such as FETs, the FETs in one of the paths both being diode-connected, and the FETs in the other path not being diode-connected. Variations in the power supply voltage result in comparable changes in the voltage drops across all four FETs, and drain-induced barrier lowering (DIBL) results in relatively small changes in gm with changes in power supply voltage.

Abstract: A bulk-modulated current source includes: an output terminal configured to supply an output current; a first transistor comprising: a first electrode coupled to the output terminal, a second electrode, a bulk electrode, and a gate electrode configured to receive a bias voltage; and an amplifier comprising: an input terminal electrically coupled to the first electrode of the first transistor, and an output terminal electrically coupled to the bulk electrode of the first transistor.

Abstract: A system for forwarding a sample rate clock along with data. In one embodiment, a sample rate clock is sent by a transmitter, along with data, to one or more receivers. The receivers sample the received data using the received sampling clock. Delay adjust circuits in the transmitter adjust the delay of each transmitted data stream using delay error sensing and correction implemented in a back channel between the receivers and the transmitter.

Abstract: An impedance circuit coupled to a first power supply includes: an output node; a transistor coupled between the output node and the first power supply, wherein the transistor comprises a gate electrode; and a voltage source electrically coupled to the gate electrode of the transistor and configured to apply a gate voltage to the gate electrode of the transistor, wherein the voltage source includes: a plurality of impedance components electrically coupled in series between a circuit node and the first power supply, and a current source electrically coupled between the circuit node and a second power supply.

Abstract: A receiver for receiving digital data after transmission through a channel which produces inter-symbol interference or other distortion. In one embodiment, a received signal is differentiated before being digitized to form an output digital bit stream, to reduce the effects of inter-symbol interference and other distortion in the channel. The differentiated signal is compared to two threshold values, a first threshold value, and a second threshold value, the first threshold value being greater than the second threshold value. When the differentiated signal exceeds the first threshold, the output bit is 1, when the differentiated signal is less than the second threshold value, the output bit is 0, and when the differentiated signal is between the first threshold value and the second threshold value, the output bit is the same as the previous output bit.

Abstract: Digital multilevel memory systems and methods include a charge pump for generating regulated high voltages for various memory operations. The charge pump may include a plurality of pump stages. Aspects of exemplary systems may include charge pumps that performs orderly charging and discharging at low voltage operation conditions. Additional aspects may include features that enable state by state pumping, for example, circuitry that avoids cascaded short circuits among pump stages. Each pump stage may also include circuitry that discharges its nodes, such as via self-discharge through associated pump interconnection(s). Further aspects may also include features that: assist power-up in the various pump stages, double voltage, shift high voltage levels, provide anti-parallel circuit configurations, and/or enable buffering or precharging features, such as self-buffering and self-precharging circuitry.

Abstract: A system for forwarding a sample rate clock along with data. In one embodiment, a sample rate clock is sent by a transmitter, along with data, to one or more receivers. The receivers sample the received data using the received sampling clock. Delay adjust circuits in the transmitter adjust the delay of each transmitted data stream using delay error sensing and correction implemented in a back channel between the receivers and the transmitter.

Abstract: A digital multilevel memory system includes a charge pump and a voltage regulator for generating regulated high voltages for various memory operations. The charge pump may include a plurality of boost circuits to boost the output of the charge pump during a fast start up. Afterwards, the boost circuits are disabled to allow the charge pump to generate high voltages without boosting. The boost circuits may be successively enabled to boost the voltage. The boost circuits may be loadless. The voltage regulator may operate in an open loop and may include a resistive divider as a reference voltage for regulating the high voltage from the charge pump. The charge pump may include spread spectrum pump clocking to reduce electromagnetic inference for capacitor or inductor on-chip charge pumping.

Abstract: A digital multilevel memory system includes a charge pump and a voltage regulator for generating regulated high voltages for various memory operations. The charge pump may include a plurality of boost circuits to boost the output of the charge pump during a fast start up. Afterwards, the boost circuits are disabled to allow the charge pump to generate high voltages without boosting. The boost circuits may be successively enabled to boost the voltage. The boost circuits may be loadless. The voltage regulator may operate in an open loop and may include a resistive divider as a reference voltage for regulating the high voltage from the charge pump. The charge pump may include spread spectrum pump clocking to reduce electromagnetic inference for capacitor or inductor on-chip charge pumping.

Abstract: Digital multilevel memory systems and methods include a charge pump for generating regulated high voltages for various memory operations. The charge pump may include a plurality of pump stages. Aspects of exemplary systems may include charge pumps that performs orderly charging and discharging at low voltage operation conditions. Additional aspects may include features that enable state by state pumping, for example, circuitry that avoids cascaded short circuits among pump stages. Each pump stage may also include circuitry that discharges its nodes, such as via self-discharge through associated pump interconnection(s). Further aspects may also include features that: assist power-up in the various pump stages, double voltage, shift high voltage levels, provide anti-parallel circuit configurations, and/or enable buffering or precharging features, such as self-buffering and self-precharging circuitry.