JPH0714033B2 - Complex integrated circuit inspection device - Google Patents

Description

TECHNICAL FIELD The present invention relates to an inspection apparatus for a composite integrated circuit.

(Prior art) Recently, due to the improvement of integrated circuit chip manufacturing technology, the integration capability of integrated circuits has dramatically improved.
Board) etc. have been assembled to form a plurality of integrated circuits integrated into one chip.

However, such a composite integrated circuit has a very large circuit configuration and a system-on-chip configuration, and it is impossible to test the whole as a single integrated circuit.

Therefore, conventionally, when inspecting a composite integrated circuit, it is divided into circuit blocks having respective functions and inspected like a single integrated circuit before being pseudo-composited.

(Problem to be Solved by the Invention) However, in the above-described conventional inspection method, it is very difficult to inspect the circuit in the interface portion between the functional blocks. That is, when each functional block is composed of complicated random logic, in order to inspect the operation of the interface part, it is necessary to inspect in the actual use mode of the entire composite integrated circuit in which each functional block is integrated. However, it was necessary to understand the entire system of the composite integrated circuit, and it was very difficult to create a test pattern.

(Means for Solving the Problem) A testing device for a composite integrated circuit according to the present invention is a composite integrated circuit in which a plurality of functional blocks and an interface portion interposed between these functional blocks are integrated in one chip. In order to inspect the interface portion between them, a test latch circuit virtual with the functional block is inserted immediately before the functional block connected to the interface portion, and the test latch circuit is the composite integrated circuit. In the inspection mode, data is written and read from the interface portion in a pseudo manner with the functional block, and is free in the actual use mode of the composite integrated circuit.

(Operation) Since the inspection latch circuit is inserted immediately before the functional block connected to the interface portion to be inspected, the inspection latch circuit is virtually simulated as the functional block in the inspection mode of the composite integrated circuit. Then, data is written and read from the interface portion. As a result, only the functional operation inspection of the interface part is performed separately from other states.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing a case in which an inspection latch circuit 1 according to the present invention is provided between an interface portion 2 and a functional block B, and FIG. 2 is a block diagram showing a configuration example of a device of a composite integrated circuit. Is.

In FIG. 1, the common bus 3 is connected from the functional block A to the inspection latch circuit 1 via the interface portion 2, and the inspection latch circuit 1 is connected to the functional block B. The interface portion 2 is composed of, for example, a standard cell, a gate array, and the like.

The test latch circuit 1 is composed of a register group for writing and reading data from the common bus 3. In the test mode, the test latch circuit 1 virtually simulates the functional block B to write and read data from the interface section 2. It functions as a latch circuit for performing, and is free in the actual use mode.

The block diagram of the device 4 of the composite integrated circuit shown in FIG. 2 illustrates a specific arrangement of the interface portion 2. That is, in FIG. 2, four functional blocks C are shown.
To F are respectively connected by the common bus 3, and in this example, the functional block C is a CPU and the functional block D is a DMAC.
Is.

Therefore, in order to test the interface portion 2, the test latch circuit 1 is used as a latch function to virtually write and read data as the functional block B, and the operation test of the interface portion 2 is performed based on the result. Is done. On the other hand, in the actual use mode, the inspection latch circuit 1 is set to the free state.

(Effects of the Invention) As described above, according to the present invention, the interface portion can be inspected without considering the state of each functional block. Therefore, the time required to create the test pattern of the interface portion can be significantly shortened, the time itself required for the inspection can be significantly reduced, and the quality of the inspection can be improved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an inspection apparatus according to the present invention, and FIG. 2 is a block diagram showing a state in which a composite integrated circuit is functionally divided. 1 ... Latch circuit for inspection 2 ... Interface part 3 ... Common bus 4 ... Devices A to F ... Functional block

Claims (1)

[Claims] 1. A composite integrated circuit in which a plurality of functional blocks and an interface portion interposed between the functional blocks are integrated in one chip, and the interface portion between the functional blocks is connected to the composite integrated circuit for inspecting the interface portion. Immediately before the functional block to be operated, a test latch circuit that is virtual with the functional block is inserted, and the test latch circuit virtually simulates the functional block in the test mode of the composite integrated circuit. A testing device for a composite integrated circuit, characterized in that data is written and read from an interface portion, and the composite integrated circuit is free during an actual use mode.