For pt.I see ibid., vol.SC-10, no.6, p.371-9 (1975). Describes techniques for performing A/D conversion compatibly with standard single-channel MOS technology. This second paper describes a two-capacitor successive approximation technique which, in contrast to the first, requires considerably less die area, is inherently monotonic in the presence of capacitor ratio errors, and which operates at somewhat lower conversion rate. Factors affecting accuracy and conversion rate are considered analytically. Experimental results from a monolithic prototype are presented; a resolution of eight bits was achieved with an A/D conversion time of 100 /spl mu/s. Used as a D/A convertor, a settling time of 12.5 /spl mu/s was achieved. The estimated total die size for a completely monolithic version including logic is 5000 mil/SUP 2/.

All-MOS charge-redistribution analog-to-digital conversion techniques. II

Describes the design and experimental results of a fully bipolar track-and-hold (T&H) circuit for use in video applications. A fully differential, open-loop approach has been chosen in order to meet the specifications with respect to track-to-hold step, droop rate, and hold-mode feedthrough. In order to obtain maximum high-frequency performance, p-n-p transistors have been omitted from the design. The T&H circuit has been realized in a 3-GHz f/sub T/ bipolar production process with a minimum emitter size of 2*9 mu m/sup 2/. The die size is 0.25 mm/sup 2/, consuming 40 mW from a single 5-V power supply. Ten-bit performance has been measured up to 12-Msample/s full-Nyquist sampling rate. At 200 Msample/2, 8-b performance has been observed over the full-Nyquist band. >

Fully bipolar, 120-Msample/s 10-b track-and-hold circuit

Methods for down converting a modulated carrier signal to a demodulated baseband signal are described herein The method requires that a first portion of energy is transferred from the modulated carrier signal, and stored at a first storage device when a first switch is on At least some of the energy stored in the first storage device is discharged when the first switch is off The method further comprises transferring a second portion of energy from the modulated carrier signal, storing at a second storage device the second portion of transferred energy when a second switch is on, and discharging at least some of the energy stored in the second storage device when the second switch is off A down-converted in-phase baseband signal portion is generated from the energy accumulated in the first storage device while both the charging and the discharging occurs, and a down-converted inverted in-phase baseband signal portion is generated from the energy accumulated in the second storage device while both the charging and the discharging occurs, and the two portions are combined with a first differential amplifier circuit to form a down-converted differential in-phase baseband signal

Method and system for down-converting an electromagnetic signal

Methods, systems, and apparatuses, and combinations and sub-combinations thereof, for down-converting and up-converting an electromagnetic (EM) signal are described herein. Briefly stated, in embodiments the invention operates by receiving an EM signal and recursively operating on approximate half cycles (½, 1½, 2½, etc.) of the carrier signal. The recursive operations can be performed at a sub-harmonic rate of the carrier signal. The invention accumulates the results of the recursive operations and uses the accumulated results to form a down-converted signal. In an embodiment, the EM signal is down-converted to an intermediate frequency (IF) signal. In another embodiment, the EM signal is down-converted to a baseband information signal. In another embodiment, the EM signal is a frequency modulated (FM) signal, which is down-converted to a non-FM signal, such as a phase modulated (PM) signal or an amplitude modulated (AM) signal. Up-conversion is accomplished by controlling a switch with an oscillating signal, the frequency of the oscillating signal being selected as a sub-harmonic of the desired output frequency.

Method and system for down-converting and up-converting an electromagnetic signal, and transforms for same

The present invention includes a system and method for ensuring reception of a communications signal. A modulating baseband signal with desired information is accepted, and a plurality of redundant spectrums is generated. Each redundant spectrum comprises the necessary amplitude, phase, and frequency information to substantially reconstruct the modulating baseband signal. It is expected but not required that the redundant spectrums will be generated at a first location and sent to a second location over a communications medium. At the second location, the redundant spectrums are independently processed to recover a demodulating baseband signal for each of the redundant spectrums. In one embodiment, an error detection process is employed at the second location to detect and eliminate those demodulated baseband signals that have been corrupted during transmission. An error-free demodulated baseband signal is selected from the remaining demodulated baseband signals. The error-free demodulated baseband signal is representative of the modulating baseband signal sent over the communications medium.

Method and system for ensuring reception of a communications signal

A monolithic sample/hold amplifier is described which includes the holding capacitor on the chip. System design considerations and tradeoffs are discussed, as well as the circuit design details. High performance is achieved by the use of a process which produces bipolar transistors and p-channel silicon-gate FET's (SIGFET's) on the same chip. Performance characteristics obtained include an acquisition time of 10 /spl mu/s (20-V step), an aperture delay time of 80 ns, and a droop rate of 30 mV/s.

K.R. Stafford

Papers

A complete monolithic sample/hold amplifier