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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This page was last edited on 7 Julyat The p-n junction that serves as such diode is overloaded with a current spike and overheated. Zener zap is frequently employed in mixed-signal circuits for trimming values of analog components. When the bulb blows, the entire mains voltage is applied across the single blown lamp.
Because the series string would be rendered inoperable by a single lamp failing, each bulb has an antifuse installed within it. In some cases a combined circuit with zeners and transistors can be used to form a zapping 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. Antifuses are best known for their use in mini-light or miniature style low-voltage Christmas tree lights.
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. An antifuse is an electrical device that performs the opposite function to a fuse. May Learn how and when to remove this template message. Amorphous silicon is a material usually not used in either bipolar or CMOS processes and requires an additional manufacturing step.
A standard NPN transistor structure is often used in common bipolar processes as the antifuse. This article needs additional citations for verification. Their disadvantage, however, is lower area efficiency compared to other types. Please help improve this article by adding citations to reliable sources.
Occasionally, the insulation fails to break down on its own, but tapping the blown lamp will usually finish the job. Ordinarily for operation from mains voltagesthe lamps are wired in series. The spike is formed on and slightly below the 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.
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.
Also circuits built via the antifuse’s permanent conductive paths may be faster than similar circuits implemented in PLDs using SRAM technology.
Antifuse – Wikipedia
Articles needing additional references from May All articles needing additional references. Antifuses are widely used to permanently program integrated circuits ICs.
Unsourced material may be challenged and removed. Formation of the conductive channel is performed by a dielectric breakdown forced by a high voltage pulse. Each bit contains both a fuse and an antifuse and is programmed by triggering one of the two.
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. Often a special bulb with no antifuse and often a slightly different rating so it blows first as the voltage gets too high known xntifuse a “fuse bulb” is incorporated programminy the string of lights to protect against the possibility of severe overcurrent if too many bulbs fail.
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.
FPGAs in computer
Retrieved from ” https: They may be less susceptible to alpha particles which can cause circuits to malfunction. From Wikipedia, the free encyclopedia. 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.
Zener diodes can be used as antifuses. In the same fashion as with the Christmas lights described above, if 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.
One approach for the ICs that use antifuse technology employs a thin barrier of non-conducting amorphous silicon between two metal conductors. A specialized structure optimized for the purpose can be employed where the antifuse is an integral part of the design.
This technology has many applications. This programming, performed after manufacturing, is permanent and irreversible.
When a sufficiently high voltage is applied across the amorphous silicon it is turned into a polycrystalline silicon-metal alloy with a low resistancewhich is conductive. 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. The terminals of the antifuses are usually accessible as bonding pads and the trimming process is performed before wire-bonding and encapsulating the chip.
By this approach, prgoramming is possible only to lower the value of the resulting resistor. Views Read Edit View history. The antifuse is usually triggered using an approximately 5 mA current. They are historically used especially with bipolar processes, where the thin oxide needed for dielectric antifuses is atifuse available.
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. Each individual street-lamp was equipped with a film cutout ; a small disk of insulating film that separated two contacts connected to the two wires leading to the lamp.
In this way, the failed lamp was bypassed and illumination restored to the rest of the street. 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.
Dielectric antifuses employ a very thin oxide barrier between a pair of conductors.