On-Chip Delay Calibration and Tracking Circuit

Enables Highly Precise Calibration of Circuit Time Delays, Using Standard Resources

This digital calibration circuit and related software installs into programmable devices or can be built into general integrated circuits for self-calibration of timing delay even under harsh temperature or voltage conditions. Almost all electronics use integrated circuits; the global market for active electronic components will have a worldwide market of $230 billion by 2017. In communication systems where delays between successive pulses are used to transmit digital signals, control of the timing delay must be precise and accurate. The timing delay of signals propagating through an integrated circuit depends on factors such as process, operating voltage and temperature. Therefore, operating in harsh environments, such as space applications in which temperature and aging are difficult to control, may be challenging. University of Florida researchers have developed a digital calibration circuit and software that can be installed directly onto an integrated circuit to increase the conversion rate of certain signal processes and to heighten the integrated circuit’s resistance to changing temperatures or voltage conditions. This circuit offers full self-calibration and environmental variation in circuits such as time-to-digital and digital-to-time converters, advancing electronics that rely upon accuracy of signal conversion. In addition, the discovery would improve upon electronics designed for space travel and satellites because of its low maintenance needs and its increased resistance to harsh environments.

Application

Precise and large-range timing calibration circuit that increases integrated circuit accuracy and environmental resistance

Advantages

• Eliminates need for external calibration, allowing for the mass production of faster, more accurate integrated circuits
• Self-calibrates under changing temperature/voltage conditions, ensuring consistent performance even in harsh environments
• Is completely integrated, requiring no external components

Technology

This combination of a circuit and an algorithm uses several Phase Locked Loops (PLL) to generate a variety of clock periods. The complete circuit can be embedded directly onto an integrated circuit, such as a time-to-digital or digital-to-time converter circuit. By embedding the Delay Locked Loop and clock as one component, it is possible to mass produce more accurate integrated circuits that can self-calibrate, ensuring consistent performance in harsh environments. This technology has been demonstrated on a field-programmable gate array.