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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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.
Antifuse – Wikipedia
In the same fashion as with the Christmas lights programmnig above, if the lamp failed, the entire voltage of the street lighting circuit thousands of volts prgoramming imposed across the insulating film in the cutout, causing it to rupture. 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 tpgas.
With a poly-diffusion anyifuse, the high current density creates heatwhich melts a thin insulating layer between polysilicon and diffusion electrodes, creating a permanent resistive silicon link. In this way, the failed lamp was bypassed and illumination restored to the rest of f;gas street. 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.
Articles needing additional references from May All articles needing additional references. The spike is formed on and slightly below the silicon surface, just below the passivation layer without damaging it.
The terminals of the antifuses are usually accessible as bonding pads and the trimming process is performed before wire-bonding and encapsulating the chip.
Dielectric antifuses employ a very thin oxide barrier between a pair of conductors. 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.
FPGAs in computer
When the failed lamp was finally changed, a new piece of film was also installed, once again separating the electrical contacts in the cutout. Zener diodes can be used as antifuses. By this approach, it is possible only to lower the value of the programmjng resistor. One approach for the ICs that use antifuse technology employs a thin barrier of non-conducting amorphous silicon between two metal conductors.
When a sufficiently high prlgramming is applied across the amorphous silicon it is turned into a polycrystalline silicon-metal alloy with a low resistancewhich is conductive. The antifuse is usually triggered using an approximately 5 mA current. Views Read Edit View history.
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 a specified limitan antifuse starts with a high resistance and is designed to permanently create an electrically conductive path typically when the voltage across the antifuse exceeds a certain level.
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.
The antifuse is made using wire with a high resistance coating and this wire is coiled over the two vertical filament support wires ptogramming the bulb.
Antifuses are best known for their use in mini-light or miniature style low-voltage Christmas tree lights. This technology has many applications. Antifuses are widely used to permanently program integrated circuits ICs.
This programming, performed after manufacturing, is qntifuse and irreversible. When the bulb blows, the entire mains voltage is applied across the single blown lamp. They are historically used especially with bipolar processes, where the thin oxide needed for dielectric antifuses is not available. This article needs additional citations for verification.
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. May Learn how and when to remove this template message. 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. Each bit contains both a fuse and an antifuse and is programmed by triggering one of the two.
Antifuses may be used in programmable read-only memory PROM. The conductive shunt therefore does not compromise integrity and reliability of the semiconductor device.
Certain programmable logic devices PLDssuch as structured ASICs progranming, use antifuse technology to configure provramming circuits and create a customized design from a standard IC 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. Unsourced material may be challenged and removed.
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. They may be less susceptible to alpha particles which can cause circuits to malfunction. Their disadvantage, programminf, is lower area efficiency compared to other types.