Electrophoresis is a valuable technique for the separation and analysis of chemical and biological specimens. Typically, an electric field is established between two electrodes that induces charged particles to move and separate. Instead of using only one electrode at each end of the separation area, this paper presents a very small, low voltage system that utilizes electrodes beneath the entire separation area, enabling better control of high electric fields using very small voltages over small areas. By employing multiple electrodes, strong electric fields can be established using very low voltages (less than 5 V) over small distances. The electrodes are also used to sense sample locations and concentrations using amperometric detection, and integrated electronics allow precise control over the fields. The system presented here includes 100 individually addressable electrodes and their corresponding circuitry on a 2 mm by 2 mm chip and is designed using the AMI 1.5 µm CMOS process available through MOSIS.

Electrophoretic separation is a key technology for DNA sequencing, environmental pathogen detection and identification, disease diagnostics, and proteomics. However, current electrophoresis systems are limited to laboratory benchtop applications due to cost and size. Even current chipbased electrophoresis systems require high voltages and are several centimeters in length, effectively preventing wide pointof-care and field use. A small (less than 1 cm), mass producible, low voltage (less than 5 V) electrophoretic system could move this powerful technology off the benchtop, out of the lab, and into wide use. A CMOS system on a chip has been proposed that would produce dynamic electric fields to dramatically reduce the operating voltages required for electrophoretic separation, and the fine resolution available in CMOS technology can be used to shorten the column lengths necessary for successful separation. Traditional circuit simulation is not suitable for a system that is characterized by electromagnetic fields and fluid behavior.A specialized mixed-domain simulation has been developed to determine the effectiveness of this system for DNA separation. Terminal restriction fragment length polymorphism (T-RFLP) analysis has been shown to be a particularly useful method of DNA analysis for pathogen identification, and its use as a feasible method on the electrophoresis system is investigated.

A mixed-signal implementation of an iterative estimate, X, of the input x[n] based on the known values of bound-based nonlinear data acquisition decoding algorithm y[n]. In [7], a detailed mathematical development of the for first-order delta-sigma (As) analog-to-digital converters proposed iterative bound-based decoding algorithm is (ADCs) is discussed. The design is partitioned into analog and presented. X ts shown to be bounded as in (1), where S[n] is digital sections which optimize the design objectives of very defined in (2). A more accurate estimation of can be small area while maintaining low power and high speed. The achieved by using the bound in (1) iteratively with n=1.L. circuit has been realized using 0.7mm2 In 0.5,um CMOS 2i .

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