The antifuse technology, routing architecture, logic mod- ule, design automation, programming, testing and use of ACTTM antifuse FPGA ‘s are described. FPGA Architectures Overview. In this short article we discuss modern FPGA architectures (SRAM-based, flash-based, antifuse- based) and their applications. Imperial College, Digital System Design. Actel FPGAs. ◇ Uses antifuse technology. ◇ Based on channelled gate array architecture as shown below.
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From Wikipedia, the free encyclopedia. Because the series string would be rendered inoperable by a single lamp failing, each bulb has an antifuse installed within it. The larger, traditional, C7 and C9 style lights are wired in parallel and are rated to operate directly at mains voltage. Each bit contains both a fuse and an antifuse and is programmed by triggering one of the two. In the same fashion as with the Christmas lights described above, anttifuse the lamp failed, the entire voltage of the street lighting circuit thousands of volts was imposed across the insulating film in the cutout, causing it to rupture.
An antifuse is zntifuse electrical device that performs the opposite function to a fuse. This programming, performed after manufacturing, is permanent and irreversible. 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 the possibility of severe overcurrent if too many bulbs fail.
Amorphous silicon is a material usually not used in either bipolar or CMOS processes and requires an additional manufacturing step. The terminals of the antifuses are usually accessible as bonding pads and the trimming process is performed before wire-bonding and encapsulating the chip. Also circuits built via the antifuse’s permanent conductive paths may be faster than similar circuits implemented in PLDs using SRAM technology. Each individual street-lamp was equipped with a film cutout ; a small disk of insulating film that separated two contacts foga to the two wires leading to the lamp.
QuickLogic Corporation refers to their antifuses as “ViaLinks” because antifhse 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 fpya.
With a poly-diffusion antifuse, the high antifude density creates heatwhich melts a thin insulating layer between polysilicon and diffusion electrodes, creating a permanent resistive silicon link.
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. When the failed lamp was finally changed, a new piece of film was also installed, once again separating the electrical contacts in the cutout.
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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. The p-n junction that serves as such diode is overloaded with a current spike and overheated.
The spike is formed on and slightly below the silicon surface, just below the passivation layer without damaging it. The resulting resistance of the junction is in the range of 10 ohms. The parallel resistors cannot have too low value as that would sink the zapping current; a series-parallel combination of resistors and antifuses is employed in such cases.
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. Formation of the conductive channel is performed by a dielectric breakdown forced by a high voltage pulse. Certain programmable logic devices PLDssuch as structured ASICsuse antifuse technology to configure logic circuits and create a customized design from a standard IC design.
They may be less susceptible to alpha particles which can cause circuits to malfunction. A specialized structure optimized for the purpose can be employed where the antifuse is an integral part of the design.
The insulation of the antifuse wire withstands the ordinary low voltage imposed across a functioning lamp but rapidly breaks down under the full mains voltage, giving the antifuse action. Please help improve this article by adding citations to reliable sources. Their disadvantage, however, is lower area efficiency compared to other types. Antifuses are widely used to permanently program integrated circuits ICs.
One approach for the ICs that use antifuse technology employs a thin barrier of non-conducting amorphous silicon between two metal conductors. Antifuses may be used in programmable read-only memory PROM. When the bulb blows, the entire mains voltage is applied across the single blown lamp.
They are antiffuse used especially with bipolar processes, where the thin oxide needed for dielectric antifuses is not available. In this way, the failed lamp was bypassed and illumination restored to the rest of the street. This article needs additional citations for verification. Ordinarily for operation from mains voltagesthe lamps are wired in series. 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 wntifuse each of the remaining lamps.
Whereas a fuse starts with a low resistance and is designed to permanently break an electrically conductive path typically when the current through the path exceeds anntifuse specified limitan antifuse starts with a high resistance and is designed to permanently create an antifude conductive path typically when the voltage across the antifuse exceeds a certain level.
Retrieved from ” https: The antifuse is usually triggered using an approximately 5 mA current. The conductive shunt therefore does not compromise integrity and reliability of the semiconductor device.
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. By this approach, it is possible only to lower the value of the resulting resistor. 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.
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.
Articles needing additional references from May All articles needing additional references. It is therefore necessary antifuae shift the manufacturing tolerances so that the lowest-value typically made is equal to or larger than the desired value.