Patent application number | Description | Published |
20120019322 | LOW DROPOUT CURRENT SOURCE - Disclosed is a low dropout current source that includes a first field effect transistor (FET), a second FET having a drain that is an output for an output voltage and an output current, and a third FET, wherein a gate of the first FET is coupled to both a gate of the second FET and a drain of the third FET, and wherein a drain of the first FET is coupled to a source of the third FET. A differential amplifier has an inverting input coupled to the drain of the first FET, a non-inverting input coupled to the drain of the second FET and an amplifier output coupled to the gate of the third FET. A current reference is coupled between the drain of the third FET and a fixed voltage node. The current reference provides a reference current that is multiplied and output from the third FET. | 01-26-2012 |
20120019405 | CURRENT DAC - A current digital-to-analog converter (DAC) is disclosed. The current DAC includes a current reference circuit coupled between a voltage source terminal and a voltage node, wherein the current reference circuit includes a feedback node. A switchable resistor network is communicably coupled to the feedback node of the current reference circuit via a first feedback network that is adapted to equalize a first voltage across the switchable resistor network voltage with a second voltage between the feedback node and the voltage node. A current mirror includes an output node communicably coupled to the switchable resistor network via a second feedback network that is adapted to equalize an output current that flows from the output node with an input current that flows into the switchable resistor network. | 01-26-2012 |
20120154015 | ANALOG MULTIPLIER - An exemplary embodiment of an analog multiplier may include a voltage controlled resistance circuit, a first transistor and a second transistor, where the resistance of the voltage controlled resistance circuit is based upon a first input voltage. The current passing through the voltage controlled resistance circuit is based upon a second input voltage. The first transistor and the second transistor form a current mirror to mirror the current passing through the voltage controlled resistance circuit to provide a power supply control current to a wideband code division multiple access radio frequency power amplifier. | 06-21-2012 |
20120154042 | ANALOG MULTIPLIER - An exemplary embodiment of an analog multiplier may include a voltage controlled resistance circuit, a first transistor and a second transistor, where the resistance of the voltage controlled resistance circuit is based upon a difference between a supply voltage and a first input voltage and a constant current supply. The current passing through the voltage controlled resistance circuit is based upon a difference between the voltage supply and a second input voltage. The first transistor may be configured to mirror the current passing through the voltage controlled resistance circuit. | 06-21-2012 |
20120218026 | METHOD OF GENERATING MULTIPLE CURRENT SOURCES FROM A SINGLE REFERENCE RESISTOR - A differential voltage controlled current source generating one or more output currents is based upon a single external resistor. The differential voltage controlled current source may generate an output current that is proportional to a received differential voltage and a bias current with the use of a single external resistor. The technique may be used to generate multiple accurate and process independent current sources. The current sources may be a zero temperature coefficient (ZTC) current, a proportional to absolute temperature (PTAT) current, or an inversely proportional to absolute temperature (NTAT) current. The output of the current sources may be inversely proportional to the resistance of the external resistor. | 08-30-2012 |
20120218032 | HIGH EFFICIENCY NEGATIVE REGULATED CHARGE-PUMP - A charge-pump circuit for providing a regulated negative voltage is disclosed. The charge-pump circuit includes at least one flying capacitor stage having a capacitor with a first terminal selectively coupled between a negative voltage input through a first electronic switch and a negative voltage output through a second electronic switch. A second terminal of the capacitor is selectively coupled between a fixed voltage node through a third electronic switch and an error signal input through a fourth electronic switch. A positive voltage source is coupled to the negative voltage output through a feedback network. A feedback amplifier having an error signal output, a reference voltage input, and a feedback input is coupled to the feedback network. A switch controller having a first clock output drives the first electronic switch and the third electronic switch, while a second clock output drives the second electronic switch and the fourth electronic switch. | 08-30-2012 |
20120326778 | CLOSED LOOP BIAS CONTROL - This disclosure relates to radio frequency (RF) amplification devices and methods for amplifying an RF input signal. To set the quiescent operating level of the RF output signal, a bias signal to be applied to the RF input signal is received prior to amplifying the RF input signal. The bias signal is amplified to generate the RF output signal at the quiescent operating level and a feedback signal is received that is indicative of the quiescent operating level of the RF output signal. Prior to amplifying the RF input signal, the bias signal level of the bias signal is adjusted such that the quiescent operating level is set to a reference signal level based on the feedback signal level. This allows for adjustments to be made to the quiescent operating level and maintain the quiescent operating level at a desired value. | 12-27-2012 |
20130088286 | METHOD OF GENERATING MULTIPLE CURRENT SOURCES FROM A SINGLE REFERENCE RESISTOR - A differential voltage controlled current source generating one or more output currents is based upon a single external resistor. The differential voltage controlled current source may generate an output current that is proportional to a received differential voltage and a bias current with the use of a single external resistor. The technique may be used to generate multiple accurate and process independent current sources. The current sources may be a zero temperature coefficient (ZTC) current, a proportional to absolute temperature (PTAT) current, or an inversely proportional to absolute temperature (NTAT) current. The output of the current sources may be inversely proportional to the resistance of the external resistor. | 04-11-2013 |
20140118074 | POWER AMPLIFIER CONTROLLER - The present disclosure provides a power amplifier controller for starting up, operating, and shutting down a power amplifier. The power amplifier controller includes current sense amplifier circuitry adapted to monitor a main current of the power amplifier. A bias generator is also included and adapted to provide a predetermined standby bias voltage and an operational bias voltage based upon a main current level sensed by the current sense amplifier circuitry. The power amplifier controller further includes a sequencer adapted to control startup and shutdown sequences of the power amplifier. In at least one embodiment, the power amplifier is a gallium nitride (GaN) device, and the main current level sensed is a drain current of the GaN device. Moreover, the bias generator is a gate bias generator provided that the power amplifier is a field effect transistor (FET) device. | 05-01-2014 |
20150070098 | RF AMPLIFICATION DEVICE WITH POWER PROTECTION DURING HIGH SUPPLY VOLTAGE CONDITIONS - Radio frequency (RF) amplification devices are disclosed along with methods of providing power to an RF signal. In one embodiment, an RF amplification device includes an RF amplification circuit and a voltage regulation circuit. The RF amplification circuit includes a plurality of RF amplifier stages coupled in cascade. The voltage regulation circuit is coupled to provide a regulated voltage to a driver RF amplifier stage. The voltage regulation circuit is configured to generate the regulated voltage so that the maximum output power of the RF amplification circuit is provided approximately at a first power level while the supply voltage is above a threshold voltage level. The first power level should be within the physical capabilities of the RF amplification circuit, and thus, the RF amplification circuit is prevented from being damaged once the supply voltage is above the threshold voltage level. | 03-12-2015 |