JPH03185376A - Hybrid integrated circuit - Google Patents

Abstract

PURPOSE:To enhance the inferiority detection power to the state of an internal data bus by mounting a connection terminal capable of taking out the data of the internal data bus from a hybrid integrated circuit through the data taking-out element on the internal data bus. CONSTITUTION:A digital circuit block 1, a digital circuit block 2 and a data taking-out element 3 each of which is constituted of a monolithic IC are mutually connected in a hybrid integrated circuit through internal data buses 4. The data taking-out element 3 has the bus data state outputting external connection terminal 6 of the hybrid integrated circuit through a data outputting wiring part 5. When the hybrid integrated circuit is operated, the state of the internal data buses can be observed one after another from the outside of the hybrid integrated circuit through the bus data state outputting external connection terminal 6. Therefore, the voltage of the data bus state outputting external connection terminal 6 is measured at the testing time of the hybrid integrated circuit to make it possible to inspect the state of the internal data buses.

Description

[Detailed description of the invention] [Industrial application field] TECHNICAL FIELD This invention relates to integrated circuits.

[Conventional technology]

In conventional hybrid integrated circuits, especially hybrid integrated circuits with digital circuits, due to the improvement in the degree of integration of monolithic ICs, the number of hybrid integrated circuits that are equipped with these monolithic ICs as is is increasing, and digital hybrid integrated circuits with an internal data bus structure are increasing. With the advent of integrated circuits, the degree of integration has increased dramatically.

However, no special processing has been carried out regarding techniques for facilitating testing of hybrid integrated circuits in response to the above-mentioned improvement in the degree of integration.

[Problem to be solved by the invention]

The above-mentioned conventional hybrid integrated circuits with digital circuits do not take any special measures to facilitate testability, so the difficulty of testing electrical characteristics has increased rapidly as the degree of integration has increased. This is a major obstacle to increasing the degree of integration of hybrid integrated circuits.

In particular, as shown in FIG. 3, in a digital hybrid integrated circuit having an internal data bus 4, it is not possible to check the data on the internal data bus 4, making it difficult to test electrical characteristics, making it difficult to detect defects. This is causing problems such as a decline in the ratio.

Furthermore, in order to solve this problem, if a terminal is provided for each data bus in a hybrid integrated circuit in order to extract information from the internal data bus, the number of terminals for measurement will increase rapidly, and the external This has led to an increase in size and a reduction in the actual degree of integration.

An object of the present invention is to make it possible to test each monolithic IC on a hybrid integrated circuit without drastically increasing the number of terminals, thereby improving the defect detection rate.

[Means to solve the problem]

The hybrid integrated circuit of the present invention includes a data retrieval element provided on a portion of the internal data bus of the hybrid integrated circuit, and information on the internal data bus can be retrieved from the hybrid integrated circuit via this element. It has a connection terminal.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a circuit block diagram of a first embodiment of the present invention.

Each digital circuit block composed of a monolithic IC 1. The digital circuit block 2 and the data retrieval element 3 are connected to each other via an internal data bus 4 inside the hybrid integrated circuit.

Further, the data retrieval element 3 provided corresponding to the internal data bus 4 has an external connection terminal 6 for outputting bus data status of the hybrid integrated circuit via a data output wiring section 5.

Here, an example is shown in which a D/A converter corresponding to the number of bits of the data bus is used as the element 3 for data extraction.

When the hybrid integrated circuit is operated, the state of the internal data bus can be observed from outside the hybrid integrated circuit via the external connection terminal 6 for sequential bus data state output.

Therefore, when testing a hybrid integrated circuit, the state of the internal data bus can be inspected by measuring the voltage of the external connection terminal 6 for outputting the data bus state. Improvement was possible.

FIG. 2 is a circuit block diagram of a second embodiment of the present invention.

Here, an example is shown in which a parallel/serial data converter corresponding to the number of bits of the data bus is used as the element 7 for data extraction.

Here, the data retrieval element 7 has an external connection terminal 9 for outputting the bus data status of the hybrid integrated circuit via a data output wiring section 8, and provides the data retrieval element 7 with a synchronization control signal necessary for data output. synchronous control signal input terminal 10 and synchronous control input signal wiring section 11 for
have.

Therefore, when testing a hybrid integrated circuit, by timely inputting a control signal from the synchronous control signal input terminal 10, the state of the internal data bus can be measured from the external connection terminal 9 for outputting the bus data state. A similar effect can be achieved.

〔Effect of the invention〕

As explained above, the present invention has a data retrieval element in the internal data bus section and a connection terminal through which information on the internal data bus can be retrieved from the hybrid integrated circuit. There is no need to significantly increase the number of external terminals.It has the effect of greatly improving the ability to detect defects in the internal data bus status of digital circuits, which has been a problem with conventional hybrid integrated circuits.

[Brief explanation of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention, FIG. 2 is a block diagram of a second embodiment of the present invention, and FIG. 3 is a block diagram of an example of a conventional hybrid integrated circuit. be. l...Digital circuit block, 2...
Digital circuit block, 3... Data retrieval element (D/A converter), 4... Internal data bus, 5... Data output wiring section, 6... ...
・External connection terminal for bus data status output, 7...
Data retrieval element (parallel/serial data converter), data output wiring section, 9... external connection terminal for bus data status output, lO... synchronous control Signal input terminal, 11... Wiring section for synchronous control input signal, 12... External connection terminal (other than external connection terminal for bus data status output).

Claims (1)

[Claims] In a hybrid integrated circuit, a data retrieval element provided on a portion of the internal data bus of the hybrid integrated circuit, and a connection terminal from which information on the internal data bus can be retrieved from the hybrid integrated circuit via this element. A hybrid integrated circuit characterized by having: