An electronic stream processing circuit with test access

Abstract

An electronic signal processing circuit contains a chain of stream processing circuits (12a-d). Linking multiplexing circuits (16a-c), link respective pairs of stream processing circuits (12a-d). Eachlinking multiplexing circuit (16a-c) is individually switchable to a normal mode and to a replacement mode. A linking multiplexing circuit (16a c), when in the normal mode, provides a continuous connection for passing a first stream of samples values between the stream processing circuits (12a-d) in the respective pair. A shareable communication structure (14a-c) is coupled to the linking multiplexing circuits (I 6a-c). Each linking multiplexing circuit (16a-c), when in the replacement mode, provides a continuous connection for supplying successive sample values from a second stream from thecommunication structure (14a-c) to a receiving one of the stream processing circuits (12a-d) in the respective pair of the linking multiplexing circuit (16a-c). A control circuit (18) keeps a selectable one of the multiplexing circuits (I6a-c) in the replacement mode so that the selectable one of the linking multiplexing circuits (16a-c) passes a stream of successive sample from the second streamto the receiving one of the processing circuits in the respective pair of linking multiplexing circuit (16a-c), while keeping at least part of the other linking multiplexing circuits (I6a-c) in the normal mode.

Description

field of invention [0001] This invention relates to electronic signal processing circuits, and more particularly to integrated signal processing circuits and the testing and configuration of such circuits. technical background [0002] Test access to integrated circuits is conventionally accomplished using scan links. In an integrated circuit with a scan chain, circuits with different functions are coupled to each other via a scan unit. In normal operating mode, the scanning unit passes binary signals from one functional circuit to another. The circuit can be switched to a test mode, wherein the scan registers of the scan units can be coupled to each other as serial shift registers. Through the serial shift register, binary signals can be transmitted to and from specific circuits in the integrated circuit. To ensure testability, the entire register of an IC is usually part of a scan chain, which usually makes access slow due to the serial shift required. The specific ord...

AI Technical Summary

Problems solved by technology

Once the network is integrated, it becomes difficult to access the circuit other than through the normal inputs and outputs

Once the circuit is integrated, limits the possibility of testing the circuit

This signal processing can be tested using a scan chain, but the test is usually very slow due to the serial shift required

During the test, the speed of the interconnected network of stream processing circuits was far from

Furthermore, when design errors make it impossible to obtain satisfactory operation, it is necessary to manufacture a redesigned integrated circuit before using the integrated circuit in a product

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