JPH01216623A - Integrated circuit - Google Patents

Abstract

PURPOSE:To attain accurate transmission of a signal by converting a voltage output signal of a circuit component into a current signal by a voltage current converter and giving the signal to an input of an optional circuit block through a programmable wire component. CONSTITUTION:A circuit block 3 is provided with an optional circuit component 31 and a voltage circuit converter 32 converting a voltage output signal of the circuit component 31 into a current signal. An input/output between optional circuit block is connected optionally by the programmable wire component to allow the user to define the function of the integrated circuit optionally locally. In this case, a signal between the circuit blocks having a problem of a voltage drop caused by the programmable wire component or the like is sent/received as the current signal via the voltage current converter to send the signal current accurately by the action of keeping it constant. In the case of transferring the analog value to other circuit block, for example, the current signal is used and in the case of transferring a digital signal to other circuit block, a voltage signal is utilized. Thus, only the required signal is converted into a current signal to attain high density of the circuit and the signal propagation characteristic is also maintained.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to an integrated circuit that allows a user to realize any functional circuit at hand by connecting arbitrary circuit blocks using programmable wiring elements. The present invention relates to an integrated circuit that prevents erroneous transmission due to a drop in signal level between circuit blocks, thereby making it possible to implement analog circuits and the like.

[Prior Art] Programmable integrated circuits such as PLDs (programmable logic devices) that are configured so that users can realize arbitrary logic circuits at hand have been known. Among them, there is a European patent EPO204034 as a PLD that can arbitrarily connect a plurality of circuit blocks by programmable wiring. These P.L.
D realizes a logic circuit that mainly handles digital signals.

On the other hand, when a user, i.e., a customer, desires an analog integrated circuit, it is generally designed and manufactured using a fully custom method. A semi-custom analog master slice has been proposed in which a mask pattern for the wiring process is created between circuit blocks according to the customer's wishes, and the final aluminum wiring is performed to realize an arbitrary analog integrated circuit.

[Problem to be solved by the invention] However, in the integrated circuit according to the above-mentioned conventional technology,
The following were the problems.

(1) PLDs allow the user to create any functional circuit at hand, but when trying to apply this to analog circuits, the voltage drop that occurs in switch elements used in programmable wiring elements, etc. This will cause an error in the analog signal transmitted by the element, and accurate operation cannot be guaranteed.

(2) Full-custom or semi-custom integrated circuits require a great deal of effort and long manufacturing processes to obtain the circuit the customer needs, although there are varying degrees of degree. The circuit function is already determined when shipped from the factory, and the user cannot change the function of the integrated circuit at hand, resulting in a lack of flexibility.

The present invention was devised to solve the above problems, and allows users to program any functional circuit including analog circuits at hand by preventing erroneous transmission due to a drop in signal level between circuit blocks. The purpose is to provide an integrated circuit that can be obtained.

[Means for Solving the Problems] The structure of an integrated circuit of the present invention for achieving the above object is as follows: In an integrated circuit comprising a plurality of circuit blocks and programmable wiring elements, at least one circuit block is , at least one circuit element and at least one
The voltage output signal of the circuit element is converted into a current signal by the voltage-current converter, and then connected to the input of any circuit block by the programmable wiring element. shall be.

[Operation] The present invention is equipped with programmable wiring elements, and connects circuit blocks composed of arbitrary circuit elements arbitrarily by programming to realize a desired functional circuit. At least part of the signal transmission and reception between the circuit blocks at this time is performed as a current signal via a voltage-current converter, thereby eliminating the effect of current propagation in which the current itself does not change even if a voltage drop occurs in wiring elements, etc. transmit signals accurately.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention.

In the integrated circuit of this embodiment, a plurality of human output pads 2 are arranged in a row on the side part of a chip 1, a plurality of circuit blocks 3 are arranged and arranged inside the chip 1, and input/output pads 2 are arranged in a row. The gaps between the circuit blocks 3 and 3 and the gaps between the circuit blocks 3 are used as wiring areas 4, and programmable wiring elements of a plurality of circuits are provided by sewing these gaps.

The circuit block 3 includes an arbitrary circuit element 31 and at least one voltage-current converter 32 that converts a voltage output signal of the circuit element 31 into a current signal. A plurality of circuit elements 31 and voltage-current converters 32 may be provided depending on the circuit function.

The output from the circuit block 3 is delivered by the current signal.

The programmable wiring elements in the wiring area 4 include, for example, the locations where the wiring of the wiring element intersects with the input/output lines of the input/output pad 2, the locations where the wiring of the wiring element intersects with the input/output lines of the circuit block 3, and the wiring of the wiring element. A programmable switch element is arranged at the point where the two intersect with each other.
It enables input/output connections between arbitrary circuit blocks 3 and between arbitrary circuit blocks 3 and arbitrary input/output pads 2.

FIGS. 2 and 3 show examples of the configuration of circuit elements that constitute the circuit block 3. FIG. FIG. 2 shows an amplifier circuit that receives output signals from other circuit blocks. This amplifier circuit has an operational amplifier 6 whose non-inverting (+) input terminal is connected to a resistor R
Connected to ground (GND) through 1, inverted (-)
An input terminal is connected to an input terminal 61 and is connected to an output terminal 62 via a resistor R. FIG. 3 is an example of a configuration in which the circuit elements themselves can programmably determine their functions. This circuit element also has an operational amplifier 7 that performs differential amplification, and its non-inverting (+) input terminal is connected to a resistor R1.
Connected to ground GND via. A resistor R4 is connected between the inverting (-) input terminal of the operational amplifier 7 and the input terminal 71.
, Rs and capacitors C, , C, are programmable switch elements St, St, s3 . S4 in series and connected in parallel with each other. Also, its inversion (−
) A transistor Tr is connected between the input terminal and the output terminal 72.
1. Resistor Ra and capacitors C5 and C are programmable switching elements Ss, S-, and Sy, respectively.
, S* are connected in series and are connected in parallel with each other.

Each of the switch elements 81 to 81 to S is controlled to turn on necessary parts using programming information stored in memory in advance, for example, turns on the resistor R4 or R6 and the transistor Tr+, and turns on the switch elements Sl or St and S. If selected, it becomes a logarithmic amplifier circuit.

In addition, by controlling the switch element Sl or S, and S, or S8 to turn on, the resistor R4 or R6 and the capacitor C5 are turned on.
Alternatively, if C3 is selected, this circuit element becomes an integrator circuit, and the switch elements S3 or S4 and S.

is turned on, capacitor CI or C1 and resistor R
If 6 is selected, a differential circuit is obtained. Furthermore, the resistor R is controlled to turn on the switch elements Sl or S, and S6.
If 4, Rs, and Rs are selected, it can be made into a simple amplifier circuit. The above is an example of circuit elements, and there are also A
Various functional circuits such as /D converters and digital circuits can be used as circuit elements.

FIG. 4 is a circuit diagram of a voltage-current converter, and shows an embodiment composed of MOS transistors.

In this embodiment, the drain of the MOS transistor 8 is connected to the circuit power supply VDD, the gate is used as the input terminal VIN for inputting the output voltage of the circuit element, and the source is the output terminal V of the circuit block. . Let's say a. Figure 5 shows this MOS transistor 8.
shows an input/output characteristic diagram of gate voltage Vc, that is, input terminal V
If the fN voltage is constant, even if the drain-source voltage vDs fluctuates due to the voltage drop of the wiring element, the drain current 1o, that is, the output terminal V, can be maintained by using the flat part of the characteristic. The output current from ut- can be made constant.

The operation of this embodiment with the above configuration will be described. In this embodiment, inputs and outputs between arbitrary circuit blocks can be arbitrarily connected using programmable wiring elements, so the user can control the functions of the integrated circuit at hand by programming the connection information of the wiring elements. Can be defined arbitrarily. At this time, signals between circuit blocks are subject to voltage drops caused by programmable wiring elements, etc.
By transmitting and receiving a current signal via a voltage-current converter, the signal current is kept constant and is accurately transmitted.

FIG. 6 is a block diagram showing another embodiment of the present invention. In this embodiment, a plurality of input/output pads 2 are arranged and arranged on the side of the chip l, a plurality of circuit blocks 3 and circuit elements 33 are arranged and arranged inside the chip l, and The gaps between the input/output pad 2 and the circuit block 3 and the circuit element 33 and the gap between the circuit block 3 or the circuit element 33 are used as wiring areas, and a plurality of flash programmable wiring elements are provided by threading through these gaps. Similar to the first embodiment, the voltage signal generated in the circuit element 31 is converted into a current signal by a voltage-current converter 32 and connected to another circuit block 3 or circuit element 33 of the circuit by a programmable wiring element. Ru. On the other hand, the voltage signal generated in the circuit element 33 is
The voltage signal is connected to another circuit block 3 or another circuit element 33 as it is.

According to the above configuration, for example, when transmitting an analog value to another circuit block, a current signal is used, and when transmitting a digital signal to another circuit block, a voltage signal is used. By converting only the signal into a current signal, it is possible to increase the density of the circuit and maintain the signal propagation characteristics.

Note that when the programmable analog circuit shown in FIG. 3 is employed as a circuit element, even more diverse functions can be defined. As described above, the present invention can be applied in various ways and can take various embodiments in accordance with its gist.

[Effects of the Invention] As is clear from the above description, the integrated circuit of the present invention can be applied to any functional circuit, such as an analog circuit, in which signal level reduction due to programmable wiring elements is a problem. Ensures accurate transmission of signals and is programmably definable at the user's fingertips.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing one embodiment of the present invention, Fig. 2, Fig. 3
4 is a diagram showing an example of the configuration of a voltage-current conversion circuit, FIG. 5 is a characteristic diagram of the voltage-current conversion circuit, and FIG. 6 is another embodiment of the present invention. FIG. 3...Circuit block, 4...Wiring area (wiring element)
, 31...Circuit element, 32...Voltage-current converter. N.D.

Claims (1)

[Claims] (1) In an integrated circuit comprising a plurality of circuit blocks and a programmable wiring element, at least one circuit block has at least one circuit element and at least one voltage-current converter, and the voltage of the circuit element is An integrated circuit characterized in that an output signal is converted into a current signal by the voltage-current converter and then connected to an input of an arbitrary circuit block by the programmable wiring element.