Analog Devices International Unlimited Company

Linear Technology Corporation

Other

Joseph Adut

Gregory A Fung

Brian D Hamilton

Jeremy Wong

Eugene Cheung

John Perry Myers

Voltage-to-current converters that include two current mirrors are disclosed. In an example voltage-to-current converter each current mirror is a complementary current mirror in that one of its input and output transistors is a P-type transistor and the other one is an N-type transistor. Such voltage-to-current converters may be implemented using bipolar technology, CMOS technology, or a combination of bipolar and CMOS technologies, and may be made sufficiently compact and accurate while operating at sufficiently low voltages and consuming limited power.

Voltage-to-current converter with complementary current mirrors

A multi-stage transimpedance amplifier (TIA) with an adjustable input linear range is disclosed. The TIA includes a first stage, configured to convert a single-ended current signal from an optical sensor of a receiver signal chain to a single-ended voltage signal, and a second stage, configured to convert the single-ended voltage signal provided by the first stage to a differential signal. In such a TIA, the input linear range may be adjusted using a clamp that is programmable with an output offset current to keep the second stage of the TIA from overloading and to maintain a linear transfer function without compression.

Transimpedance amplifiers with adjustable input range

An example analog signal multiplexer includes two differential input signal ports for receiving a first and a second differential input signals, INand IN. The multiplexer further includes a differential output signal port with two output terminals OUT+ and OUT&#x2212;, for outputting a signal based on one or more of the input signals INand IN. Furthermore, the multiplexer includes a pair of load elements, and an additional differential output signal port that has two output terminals TERM+ and TERM&#x2212;. The load elements are not coupled directly to the output terminals OUT+ and OUT&#x2212;, but, rather, are coupled to the output terminals of the additional output signal port, TERM+ and TERM&#x2212;, enabling a modular approach where multiple instances of the multiplexer may be combined on an 'as-needed' basis to realize multiplexing between a larger number of differential inputs that a single multiplexer would allow.

Modular analog signal multiplexers for differential signals

Differential clamp circuits configured to recirculate the current in one clamp, either low-side clamp or high-side clamp, from one output of a differential signal to the other output of the differential signal are disclosed. Differential clamp circuits described herein may be particularly suitable for providing programmable clamps at differential outputs of an ADC driver and may be particularly beneficial to implement clamps that are symmetrical around an ADC's input common-mode voltage. Some differential clamp circuit described herein may advantageously present a smaller capacitive load at each output, thus reducing bandwidth degradation of the output stage. Furthermore, differential clamp circuits described herein may operate with only one control voltage, making it easier to limit the output excursions symmetrically around the default common-mode voltage.

Differential clamp circuits with current recirculation

A high-speed low-noise trans-impedance amplifier (TIA) with fast overdrive recovery is suitable for use in light detection and ranging (LIDAR) receivers.

Trans-impedance amplifier with fast overdrive recovery

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.

Unity gain buffer with two states

A differential amplifier may, when connected to a positive or negative supply voltage and to a ground voltage, provide a differential pair of outputs signals at a differential output that are an amplification of a differential pair of input signals at a differential input. A differential input stage may receive the differential pair of input signals from the differential input and may include a first transistor associated with one of the input signals and a second transistor associated with the other input signal. A differential output stage may generate the differential pair of output signals at the differential output and may include a third transistor associated with one of the output signals and a fourth transistor associated with the other output signal. The first, second, third, and fourth transistors may be all P type or all N type. The differential pair of output signals may have a common mode that is: near the ground voltage when the first, second, third, and fourth transistors are all N type and the supply voltage is positive with respect to the ground voltage; near the supply voltage when the first, second, third, and fourth transistors are all P type and the supply voltage is positive with respect to the ground voltage; near the ground voltage when the first, second, third, and fourth transistors are all P type and the supply voltage is negative with respect to the ground voltage; or near the supply voltage when the first, second, third, and fourth transistors are all N type and the supply voltage is negative with respect to the ground voltage.

Level-shifting amplifier

A DC-coupled differential amplifier has an output common-mode voltage near the ground reference. A feedback circuit superimposed on a trans-linear loop improves linearity and extends the bandwidth of the basic PNP differential pair.

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Palo Alto, CA, United States of America

Joseph Adut