Mixed Signal ASICs

Tekmos has two approaches to high temperature operation. Our basic 0.35u ASIC process performs well up to 200ºC operation. Above there, the leakage currents become noticeable and may affect circuit operation. The leakages become excessive above 220ºC, and may damage the circuit.

Tekmos is well positioned to meet your mixed signal requirements. Most of the Tekmos gate arrays contain small analog arrays for use in mixed signal applications. These can reduce the NREs substantially. We can interface at any level, from doing everything, or as little as implementing your physical layout.

Mixed Signal

Since most of our advanced processors have embedded 16-bit ADC capability, the role of the Tekmos mixed signal ASIC is to provide an interface between sensors and the ADC by providing amplification, filtering, and impedance matching.

For example, an application may require connecting a microphone to the system. The microphone needs a biasing circuit, a gain control, and an amplifier so that the full range of the microphone is matched to the ADC. This can be implemented using 10 to 20 discrete components or embedded in a Tekmos mixed signal ASIC.

Mixed Signal Implementation

Tekmos uses an approach called structured arrays to implement our mixed signal designs. It provides many advantages. Tekmos may already have an array that we can use for your project, reducing NRE charges.

Even if we do have to make a new structured array for your project, we can frequently start wafers before the design is complete, since it is only the later processing steps that implement your specific circuit. This approach reduces the overall cycle time by about 5 weeks.

Mixed signal devices typically require a revision in order to meet system requirements. With the structured array approach, a revision usually requires only two masks reducing cost and cycle time.

Mixed Signal Design Flow

A mixed signal design begins with the specifications. After listening to your requirements we develop a detailed specification. It is typically revised until it is satisfactory to both parties.

In some cases, we may provide a breadboard of the proposed circuit so that the design can be verified in your system. In other cases, your previous design can serve as a proof of functionality.

We then design the analog part of your circuit. Often, we work on the digital part in parallel. When complete, we merge the analog and digital portions into a single chip.

After layout, we extract the post route capacitances and re-run our simulations to insure that the design still meets your requirements. After a final design review, we tape out and generate your prototypes. Production occurs after prototype approval.