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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Whereas antifuss 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 pfga 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.
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. The spike is formed on and slightly below the silicon surface, just below the passivation layer without damaging it.
Zener diodes can be used as antifuses. 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.
For example a precision resistor can be manufactured by fpgq 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.
The insulation of the antifuse wire withstands the ordinary low voltage imposed across a fpgga lamp but rapidly breaks down under the full mains voltage, giving the antifuse action. Antifuses are best known for their use in mini-light or miniature style low-voltage Christmas tree lights. Antifuses may be used in programmable read-only memory PROM.
Dielectric antifuses employ a very thin oxide barrier between a pair of conductors. When the failed lamp antiuse finally changed, a new piece of film was also installed, once again separating the electrical contacts in the cutout. Their disadvantage, however, is lower area efficiency compared to other types.
Antifuse – Wikipedia
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.
The terminals of the antifuses are usually accessible as bonding pads and the trimming process is performed before wire-bonding and encapsulating the chip. Articles needing additional references from May All articles needing additional references. This technology has many applications. 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.
antifuse Definition from PC Magazine Encyclopedia
Amorphous silicon is a material usually not used in either bipolar or CMOS processes and requires an additional manufacturing step. Unsourced material may be challenged and removed.
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Antifuses are widely used to permanently program integrated circuits ICs. The p-n junction that serves as such wntifuse is overloaded with a current spike and overheated.
Zener zap is frequently employed in mixed-signal circuits for trimming values of analog components.
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. 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.
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. Because the series string would be rendered inoperable by a single lamp failing, each bulb has an antifuse installed within it.
Certain programmable logic devices PLDssuch as structured ASICsuse antifuse technology to configure logic circuits and create a customized design from a standard IC design.
Ordinarily for operation from mains voltagesthe lamps are wired in series. By this approach, it is possible only to lower the value of the resulting resistor. This article needs additional citations for verification.
Views Read Edit View history. They are historically used fpta with bipolar processes, where the thin oxide needed for dielectric antifuses is not available.
When the bulb blows, the entire mains voltage is applied across the single blown lamp. 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. In a similar fashion to that of Christmas tree lights, before the advent of high-intensity discharge lampsstreet light circuits using incandescent light bulbs fpfa often operated as high-voltage series circuits.
The antifuse is usually triggered using an approximately 5 mA current. The resulting resistance of the junction is in the range of 10 ohms. 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.
Each individual street-lamp was equipped wntifuse a film cutout ; a small disk of anrifuse film that separated two contacts connected to the two wires leading to the lamp.