FPGA (Field Programmable Gate Array) is an integrated circuit FPGA devices are produced by a number of semiconductor basic modes of programming: Antifuse-based FPGAs are different from the previous ones in that they can be. That is where the Field Programmable Gate Arrays (FPGAs) become of interest! They are hardware The antifuse programming technology is the simplest one. ❖The Programming technology. ❖The basic logic cells. ❖The I/O logic cells. ❖ Programmable interconnect. ❖Software to design and program the FPGA.
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Antifuses progfamming widely used to permanently program integrated progtamming ICs. Unlike Christmas lights, the circuit usually contained an automatic device to regulate the electric current flowing in the circuit, preventing the current from rising as additional lamps burned out. One approach for the ICs that use antifuse technology employs a thin barrier of non-conducting amorphous silicon between two metal conductors.
With a poly-diffusion antifuse, the high current density creates heatwhich melts a thin insulating layer between polysilicon and diffusion electrodes, creating a permanent resistive silicon link.
Amorphous silicon is a material usually not used in either bipolar or CMOS processes and requires an additional manufacturing step. May Learn how and when to remove this template message. Antifuses may be used in programmable read-only memory PROM.
This programming, performed after manufacturing, is antfiuse and irreversible. This article needs additional citations for verification.
The resulting resistance of the junction is in the range of 10 ohms. Also circuits built via the antifuse’s permanent conductive paths may be faster than similar circuits implemented in PLDs using SRAM technology.
As the number of bonding pads is limited for a given size of the chip, various multiplexing strategies are used for larger number of antifuses. In a similar fashion to that of Christmas tree lights, before the advent of high-intensity discharge lampsstreet light circuits using incandescent light bulbs were often operated as high-voltage series circuits.
Certain programmable logic devices PLDssuch as structured ASICsuse antifuse technology to configure logic circuits and create a customized design from a standard IC design.
For example a precision resistor can be manufactured by forming several series resistors with Zeners in parallel oriented to be nonconductive during normal operation of the device and then shorting selected Zeners to shunt the unwanted resistors.
Their disadvantage, however, is lower area efficiency compared to other types.
Often a special bulb with no antifuse and often a slightly different rating so it blows first as the voltage gets too high known as a “fuse bulb” is incorporated into the string of lights to protect against probramming possibility of severe overcurrent if too many bulbs fail. Each individual street-lamp was equipped with a film cutout ; a small disk of insulating lrogramming that separated two contacts connected to the two wires leading to the lamp. Retrieved from ” https: An antifuse is an electrical device that performs the opposite function to a fuse.
When the failed lamp was finally changed, a new piece of film was also installed, once again separating the electrical contacts in the cutout. This page was last edited on 7 Julyat In this way, the failed lamp was bypassed and illumination restored to the rest of the street.
Dielectric antifuses employ a very thin oxide barrier between a pair of conductors. Ordinarily for operation from mains voltagesthe lamps are wired in series.
A standard NPN transistor structure is often used in common bipolar processes as the antifuse. Because the series string would be rendered inoperable by a single lamp failing, each bulb has an antifuse installed within it.
Occasionally, the insulation fails to break down on its own, but tapping the blown lamp will usually finish the job. They are historically used especially with bipolar processes, progrxmming the thin oxide needed for dielectric antifuses is not available.
In some cases a combined circuit with zeners and transistors can be used to form a fpgae matrix; with additional zeners, the trimming which uses voltages higher than the normal operational voltage of the chip can be performed even after packaging the chip.
The larger, traditional, C7 and C9 style lights are wired in parallel and are rated to operate directly at mains voltage. The antifuse is usually triggered using an approximately 5 mA current.
FPGAs in computer
It is therefore necessary to shift the manufacturing tolerances so that the lowest-value typically made is equal to or larger than the desired value. Zener diodes can be used as antifuses. Articles needing additional references from May All articles needing additional atifuse. The p-n junction that serves as such diode is overloaded with a current spike and overheated.
From Wikipedia, the free encyclopedia.
Antifuse – Wikipedia
The antifuse is made using wire with a high resistance coating and this wire is coiled over the two vertical filament support wires inside the bulb. Views Read Edit View history.
The spike is formed on and slightly below anttifuse silicon surface, just below the passivation layer without damaging it. QuickLogic Corporation refers to their antifuses as “ViaLinks” because blown fuses create a connection between two crossing layers of wiring on the chip in the same way that a via on a printed circuit board creates a connection between copper layers.
This rapidly causes the antifuse to short out the blown bulb, allowing the series circuit to resume functioning, albeit with a larger proportion of the mains voltage now applied to each of the remaining lamps. A specialized structure optimized for the purpose can be employed where the antifuse is an integral part of the design.
Unsourced material may be challenged and removed. Antifuses are best known for their use in mini-light or miniature style low-voltage Christmas tree lights. The terminals of the antifuses are usually accessible as bonding pads and the trimming process is performed before wire-bonding and encapsulating the chip.
In the same fashion as with the Christmas lights described above, if the lamp failed, the entire prlgramming of the street lighting circuit thousands of volts was imposed across the insulating film in the cutout, causing it to rupture. This technology has many applications. They may be less susceptible to alpha particles which can cause circuits to malfunction.
The parallel resistors cannot have too low value as that would sink the zapping current; a programning combination of resistors and antifuses is employed in such cases.