Patent classifications
H03F2203/45356
Wideband low noise amplifier having DC loops with back gate biased transistors
Methods form amplifier device structures that include first-third amplifier devices. The first amplifier device produces an intermediate signal. The second amplifier device is connected to an input of the first amplifier device and produces an amplified inverted output signal. The third amplifier device inverts the intermediate signal to produce an amplified non-inverted output signal that is complementary to the amplified inverted output signal. A resistor feedback loop is connected to the input and output of the first amplifier device. A gain ratio of the gain of the third amplifier device to the gain of the second amplifier device matches a resistance ratio of the source resistance of the input signal to the resistance of the resistor added to the source resistance. Also, DC loop circuits are connected to the first-third amplifier devices, and each of the DC loop circuits connects an amplifier device output to an amplifier device input.
Auto-zero technique for opamps with a source-follower output stage based on replica referencing
An electronic circuit comprises an input stage, a gain stage operatively coupled to the input stage, a primary output stage operatively coupled to the gain stage, a replica output stage operatively coupled to the gain stage in parallel to the primary output stage, and a clock circuit. The clock circuit operates the electronic circuit in multiple phases including a sampling phase to disconnect the primary output stage and the replica output stage from the gain stage to obtain an offset voltage, an active phase to reconnect the primary output stage to apply the offset voltage to reduce an offset at the primary output stage, and an intermediate phase to first reconnect the replica output stage to the gain stage prior to the active phase.
COMMON MODE OVERLOAD RECOVERY FOR AMPLIFIER
A circuit includes a first transistor having a first control input and first and current terminals. The circuit also includes a second transistor having a second control input and third and fourth current terminals. The third current terminal couples to the first current terminal at a first node. An output stage has a first input, a second input, and an output stage output. The first input couples to the fourth current terminal, and the second input couples to the second current terminal. A resistor has first and second resistor terminals. The first resistor terminal couples to the output stage output, and the second resistor terminal couples to the second control input. A third transistor has a third control input, a fifth current terminal, and a sixth current terminal. The fifth current terminal couples to the first resistor terminal, and the sixth current terminal couples to the second resistor terminal.
CHOPPER-STABILIZED PROGRAMMABLE GAIN AMPLIFIER
A circuit including an amplifier having an input and an output. The circuit also includes a current-to-voltage amplifier having an input. The circuit further includes a current mirror coupled between the output of the amplifier and the input of the current-to-voltage amplifier. The current mirror is configured to chop current flowing through the first current mirror.
AUTO-ZERO TECHNIQUE FOR OPAMPS WITH A SOURCE-FOLLOWER OUTPUT STAGE BASED ON REPLICA REFERENCING
An electronic circuit comprises an input stage, a gain stage operatively coupled to the input stage, a primary output stage operatively coupled to the gain stage, a replica output stage operatively coupled to the gain stage in parallel to the primary output stage, and a clock circuit. The clock circuit operates the electronic circuit in multiple phases including a sampling phase to disconnect the primary output stage and the replica output stage from the gain stage to obtain an offset voltage, an active phase to reconnect the primary output stage to apply the offset voltage to reduce an offset at the primary output stage, and an intermediate phase to first reconnect the replica output stage to the gain stage prior to the active phase.
Unity gain buffer with two states
A unity gain buffer provides an ON state in which the input signal is coupled to the output terminal and an OFF state in which the input signal is isolated from the output terminal. Multiple unity gain buffers may share the same load to form a voltage-mode maximum follower or a multiplexer.
Superposition Operation Circuit and Float-Voltage Digital-to-Analog Conversion Circuit
A superposition operation circuit and a float-voltage digital-to-analog conversion circuit to superpose analog elements according to an indirect current superposition principle, where a voltage follower is implemented using a first operational amplifier such that an output end of the voltage follower is clamped to a voltage that is input to a positive-phase input end, namely, a to-be-superposed analog element. Then a current generation circuit converts a voltage signal to a current signal, a voltage drop for the current signal is generated on a first resistor coupled to an output end of the first operational amplifier, and the voltage drop is superposed on a voltage signal output by the first operational amplifier.
OFFSET ADDITION CIRCUITS FOR SENSE TRANSISTORS
In examples, an apparatus for sensing current comprises a power transistor; a sense transistor coupled to the power transistor; and an offset addition circuit coupled to the power transistor and the sense transistor, the offset addition circuit comprising a first pair of transistors and a differential amplifier. The apparatus also comprises a cascode amplifier circuit coupled to the offset addition circuit, the cascode amplifier circuit comprising a second pair of transistors, and a gain trim circuit coupled to the cascode amplifier circuit, the gain trim circuit including another differential amplifier and a third transistor. The apparatus further includes an analog-to-digital converter (ADC) coupled to the gain trim circuit and storage coupled to the ADC.
LOW-VOLTAGE DIFFERENTIAL SIGNALING (LVDS) RECEIVER CIRCUIT AND A METHOD OF OPERATING THE LVDS RECEIVER CIRCUIT
The invention provides a Low-voltage Differential Signaling (LVDS) receiver circuit that comprises a folded-cascode operational transconductance amplifier (OTA) that includes a pair of input branches and a pair of output branches. The pair of input branches of the folded-cascode OTA includes a p-channel metal-oxide semiconductor (PMOS) input transistor pair connected to a first supply voltage domain. The pair of output branches includes an output circuit connected to a second supply voltage domain. The LVDS receiver circuit further includes a common-mode feedback circuit connected to the pair of output branches of the folded-cascode OTA that controls the second supply voltage domain. The LVDS receiver circuit further includes a regenerative buffer circuit connected to the pair of output branches of the folded-cascode OTA and an output generated from the pair of output branches of the folded-cascode OTA directly operates the regenerative buffer circuit to produce a distortion-free output signal.
WIDEBAND LOW NOISE AMPLIFIER HAVING DC LOOPS WITH BACK GATE BIASED TRANSISTORS
Methods form amplifier device structures that include first-third amplifier devices. The first amplifier device produces an intermediate signal. The second amplifier device is connected to an input of the first amplifier device and produces an amplified inverted output signal. The third amplifier device inverts the intermediate signal to produce an amplified non-inverted output signal that is complementary to the amplified inverted output signal. A resistor feedback loop is connected to the input and output of the first amplifier device. A gain ratio of the gain of the third amplifier device to the gain of the second amplifier device matches a resistance ratio of the source resistance of the input signal to the resistance of the resistor added to the source resistance. Also, DC loop circuits are connected to the first-third amplifier devices, and each of the DC loop circuits connects an amplifier device output to an amplifier device input.