Apparatus for inserting delay, nuclear medicine imaging apparatus, method for inserting delay, and method of calibration

Abstract

An apparatus and method for inserting delay into a start signal of a metastable ring oscillator chain-based time-to-digital circuit (TDC). Included therein is a signal generating circuit that generates the start signal, a plurality of carry elements connected as a chain, each of the carry elements having an input to receive a stop signal, a delay chain circuit including one or more delay modules selected from the plurality of carry elements, at least one feedback line connected between at least one of the delay modules and the signal generating circuit, and a plurality of enable inputs each provided in a respective one of the delay modules. The delay chain circuit generates an amount of delay based on a delay selection signal that is received at the enable inputs and that selects the amount of delay. The delay chain circuit additionally provides the selected amount of delay to the signal generating circuit, which incorporates the delay into the start signal.

Description

technical field [0001] Embodiments of the invention relate to a device for inserting delay, a nuclear medicine imaging device, a method for inserting delay, and a method for correcting. Background technique [0002] A time-to-digital converter (Time-to-Digital Converter: TDC) is often used to measure time by a gamma ray detector (detector). TDC converts the realization of an event accurately into a number that can be correlated with the time when the event occurred. To achieve this task, various methods exist. In order to achieve this task, the step of counting a number of very high-speed logic transitions between large clock cycles is used. Depending on the situation, it is sometimes desirable to show the occurrence of a series of events that occur in succession. For example, the time it takes for a rising signal to reach a predetermined threshold can be very useful information. [0003] The time-to-digital converter is implemented in various configurations, such as a c...

AI Technical Summary

Problems solved by technology

[0006] In order to improve the timing accuracy of TDCs based on single-edge delay columns, large offsets can be programmed into TDCs to take advantage, but there are significant manufacturing-induced variations in the speed of the circuits on the chip

This variation has an effect on the optimal delay between edges that should be used to extract maximum accuracy from the TDC circuit population

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