摘要:
Methods of using one of a plurality of configuration bitstreams in an integrated circuit are disclosed. An exemplary method comprises analyzing the plurality of implementations of a design to determine initial variations in timing among the implementations; modifying the implementations to reduce the variations in timing among the implementations; and outputting a plurality of configuration bitstreams for the implementations having variations in timing that are reduced relative to the initial variations in timing. Another method comprises generating a plurality of implementations for the design; generating a cost function for the design based upon costs (e.g., collision penalties) derived from at least two of the plurality of implementations; determining a cost for each implementation based upon the cost function; optimizing an implementation of the design by minimizing the cost of the implementation; generating a plurality of configuration bitstreams for the plurality of implementations; and outputting the plurality of configuration bitstreams.
摘要:
An embodiment of a method to characterize a die is disclosed. The embodiment of the method includes measuring a quality metric of the die, and determining, prior to a final test stage, whether the quality metric of the die satisfies a first constraint, where the first constraint is more stringent than a second constraint at the final test stage for the quality metric of the die.
摘要:
A method and apparatus for authenticating a bitstream used to configure programmable devices are described. In an example, the bitstream is received via a configuration port of the programmable device, the bitstream including instructions for programming configuration registers of the programmable device and at least one embedded message authentication code (MAC). At least a portion of the instructions is initially stored in a memory of the programmable device without programming the configuration registers. At least one actual MAC is computed based on the bitstream using a hash algorithm. The at least one actual MAC is compared with the at least one embedded MAC, respectively. Each instruction stored in the memory is executed to program the configuration registers until any one of the at least one actual MAC is not the same as a corresponding one of the at least one embedded MAC, after which any remaining instructions in the memory are not executed.
摘要:
A method of enabling detection of tampering with data provided to a programmable integrated circuit is described. The method comprises modifying a portion of the data to establish randomness in the data; and inserting, by a computer, a redundancy check value in the portion, wherein the redundancy check value is based upon the modified portion of the data. A programmable integrated circuit is also described.
摘要:
An integrated circuit includes a fingerprint element and a decryption circuit. The fingerprint element generates a fingerprint, where the fingerprint is reproducible and represents an inherent manufacturing process characteristic unique to the integrated circuit device. The decryption circuit decrypts, using a decryption key that is based on the fingerprint, an encrypted data in order to extract data. In one embodiment, the propagation delay of various circuit elements are used to generate the fingerprint. In another embodiment, the specific frequency of an oscillator is used to generate the fingerprint. In yet another embodiment, a ratio of measurable values is used to generate the fingerprint. In another embodiment, differences in transistor threshold voltages are used to generate the fingerprint. In yet another embodiment, variations in line widths are used to generate the fingerprint.
摘要:
Dynamic power savings and efficient use of resources are achieved in a programmable logic device (PLD) such as a field programmable gate array (FPGA) or complex programmable logic device (CPLD) by receiving a design netlist specifying a circuit including clock signals, clock buffers, clock enable signals and synchronous elements, examining the design netlist to identify synchronous elements coupled to common clock and clock enable signals, cutting the clock signals to the synchronous elements to form a modified design netlist, inserting gated clock buffers into the modified netlist to output gated clock signals to the synchronous elements, responsive to the clock enable signals, and performing placement and routing on the modified netlist. A system for performing the method on an EDA tool is provided. The methods may be provided as executable instructions stored on a computer readable medium which cause a programmable processor to perform the methods.
摘要:
Methods of providing error correction in configuration bitstreams for programmable logic devices (PLDs). While any error correction method can be used, in one embodiment a Hamming code is applied to instructions in the configuration bitstream, while a product code is applied to configuration data. Thus, the higher overhead required for a Hamming code applies to only a few words in the bitstream. The instructions are corrected on receipt of the word that includes the Hamming code, so the instructions are executed correctly even if a transmission error has occurred. However, configuration data can be stored in the configuration memory without correction. With a product code, the exact location of an erroneous bit is not known until the end of the transmission, when a parity word is received. At this time, the PLD can go back and correct erroneous bits in the configuration data prior to enabling the newly loaded design.
摘要:
Methods of enabling the validation of an integrated circuit adapted to receive one of a plurality of configuration bitstreams for a circuit design is disclosed. The method comprises analyzing a plurality of implementations for the circuit design; determining minimum timing constraints based upon all of the implementations for the circuit design; generating a representative implementation, based upon the plurality of implementations, which meets the determined minimum timing constraints for all of the implementations of the circuit design; and outputting the representative implementation.
摘要:
Various approaches for detection of an unwanted function implemented in an integrated circuit (IC) are described. A controller is implemented on the IC, and at a first time while the IC is operating according to a circuit design, the controller reads a first data set from a subset of memory cells. The subset of memory cells stores state information of the circuit design. The controller determines whether the first data set is different from a second data set. In response to the first data set being different from the second data set, the controller outputs a threat signal that indicates the presence of unauthorized logic in the circuit design.
摘要:
Methods of detecting unwanted logic in an integrated circuit (IC) design. Any unwanted logic added to a design (e.g., to monitor or interfere with operation of the design) will draw power from one or more power supplies on the IC. Hence, by monitoring power drawn from various portions of a circuit design implemented in an IC, the unwanted logic can be detected and reported to the user. One way of monitoring power draw is by the use of oscillator circuits. If power goes down locally (e.g., due to the operation of unwanted logic), the frequency of an oscillator circuit in that vicinity will be reduced relative to the frequencies of other oscillator circuits in the design, and/or relative to an expected value. When a variation in the relative power consumption is detected, unwanted logic can be inferred and an error signal is output.