Programmable Analog Modulator/Demodulator

Technology #3490

A large-scale field-programmable analog array (FPAA) for rapidly prototyping analog systems and an arbitrary analog waveform generator. The large-scale FPAA includes a floating-gate transistor array and a plurality of computational analog blocks (CABs), which may be adapted to set bias voltages for operational transconductance amplifiers (OTAs), adjust corner frequencies on the capacitively coupled current conveyors, set multiplier coefficients in vector-matrix multipliers, and a variety of other operations. The floating-gate transistors may be used as switch elements, programmable resistor elements, precision current sources, and programmable transistors. Accordingly, the floating-gate transistors within the array allow on-chip programming of the characteristics of the computational elements, while still maintaining compact CABs. The arbitrary analog waveform generator may include programmable floating-gate MOS transistors for use as analog memory cells to store samples of the waveforms.

Briefly described, the present invention comprises a large-scale field-programmable analog array (FPAA) for rapidly prototyping analog systems. The present invention may be used in analog circuit development, for various methods of prototyping analog systems, and for analog modulator/demodulators using a programmable arbitrary waveform generator. The large-scale FPAA includes a floating-gate transistor array and a plurality of computational analog blocks (CABs), which may be adapted to set bias voltages for operational transconductance amplifiers (OTAs), adjust corner frequencies on the capacitively coupled current conveyors, set multiplier coefficients in vector-matrix multipliers, and a variety of other operations. The floating-gate transistors may be used as switch elements, programmable resistor elements, precision current sources, and programmable transistors. Accordingly, the floating-gate transistors within the array allow on-chip programming of the characteristics of the computational elements, while still maintaining compact CABs.

A notable feature of the present invention is the use of the transistors in the floating-gate transistor array as both switching elements for routing signals and as programmable elements for manipulating the signal being routed. By using the transistors as multi-purpose elements, greater flexibility may be achieved in implementing designs using the present invention.

In another embodiment of the present invention, a modulator/demodulator (PAMD) for analog signal processing applications is provided. The PAMD is implemented on a single chip architecture and is fully programmable, thereby allowing the PAMD to be used for a variety of communication schemes without specificity to a particular application. The PAMD includes an arbitrary analog waveform generator to generate waveforms, where programmable floating-gate MOS transistors may be used as analog memory cells to store samples of the waveforms.