Abstract: 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.

Abstract: A system for securely using decryption keys during FPGA configuration includes a FPGA having a microcontroller for receiving a bitstream having an encrypted bitstream portion as well as a configuration boot program. The configuration boot program can be code that runs on an embedded hardware microcontroller or a software microcontroller. The system further includes a key storage register coupled to the microcontroller for storing key data from the microcontroller, a decryptor coupled to the key storage register, and a configuration data register in the FPGA. Preferably, only the decryptor can read from the key storage register and the configuration data register cannot be read by the microcontroller after the decryptor is used.

Abstract: Methods and structures utilizing multiple configuration bitstreams to program integrated circuits (ICs) such as programmable logic devices, thereby enabling the utilization of partially defective ICs. A user design is implemented two or more times, preferably utilizing different programmable resources as much as possible in each configuration bitstream. The resulting user configuration bitstreams are stored along with associated test bitstreams in a memory device, e.g., a programmable read-only memory (PROM). Under the control of a configuration control circuit or device, the test bitstreams are loaded into a partially defective IC and tested using an automated testing procedure. When a test bitstream is found that enables the associated user design to function correctly in the programmed IC, i.e.

Abstract: Methods of enabling the use of defective programmable devices. The method comprises performing functional testing for each programmable device of a plurality of programmable devices; identifying each programmable device of the plurality of programmable devices having a defective portion of programmable blocks; identifying, for each programmable device which is identified to have a defective portion of programmable blocks, a location of the defective portion; and storing, for each programmable device which is identified to have a defective portion of programmable blocks, the location of the defective portion on the programmable device.

Abstract: Method and apparatus for integrating capacitors in stacked integrated circuits are described. One aspect of the invention relates to a semiconductor assembly having a carrier substrate, a plurality of integrated circuit dice, and at least one metal-insulator-metal (MIM) capacitor. The integrated circuit dice are vertically stacked on the carrier substrate. Each MIM capacitor is disposed between a first integrated circuit die and a second integrated circuit die of the plurality of integrated circuit dice. The at least one MIM capacitor is fabricated on at least one of a face of the first integrated circuit die and a backside of the second integrated circuit die.

Abstract: Methods of securing a programmable logic device (PLD) when an intrusion attempt is detected, e.g., methods of erasing sensitive data from the PLD or disabling configuration of the PLD in response to an attack. For example, when an attempt is made to configure the PLD with an unauthorized bitstream, a decryption key stored on the PLD can be erased, or decryption logic in the PLD can be otherwise disabled. The criteria for assuming that an attack is in progress can include, for example, the lack of a cyclic redundancy check (CRC) value included with a configuration bitstream, an attempt to operate the PLD outside normal operating ranges, receipt of an incorrect CRC value, or receipt of a predetermined number of bitstreams including incorrect CRC values. In some embodiments, an error correction procedure is performed on the bitstream, thereby preventing most transmission errors from being incorrectly interpreted as an attack.

Abstract: 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.

Abstract: A random access memory (RAM) in a programmable logic device (PLD) supports error correction as well as a configurable data width. The number of bits in a user data word varies by the selected configuration of the RAM, while the number of bits in the error correction code (ECC) is unvarying, and is based on the total width of the memory. In some embodiments, separate ports are provided for the user data and the ECC data. Thus, ECC data can be written to an ECC portion of the RAM array at a given RAM address, while at the same time user data is written to or read from a configurable user data portion of the RAM array at the same RAM address. In other embodiments, a single memory access port is used for both user data and ECC data.

Abstract: An integrated circuit with a through-die via (TDV) interface for die stacking is described. One aspect of the invention relates to an integrated circuit die having an array of tiles arranged in columns. The integrated circuit die includes at least one interface tile. Each interface tile includes a logic element, contacts, and through die vias (TDVs). The logic element is coupled to a routing fabric of the integrated circuit die. The contacts are configured to be coupled to conductive interconnect of another integrated circuit die attached to the backside of the integrated circuit die. The TDVs are configured to couple the logic element to the contacts.

Abstract: Method and apparatus for processing configuration data for a programmable logic device is described. The configuration data includes a sequence of frames. In one example, bits in the sequence of frames are identified as “don't care” bits that do not affect the functionality of a design implemented in the programmable logic device. Frames in the sequence of frames are compared to identify at least one set of identical frames, where the “don't care” bits are deemed to result in matches. Each of the at least one set of identical frames is merged to produce a respective at least one merged frame. Each of the at least one merged frame is associated with a plurality of configuration memory addresses in the programmable logic device. Each of the at least one merged frame may be loaded into configuration memory of the programmable logic device using a multi-frame write process.

Abstract: Methods and structures utilizing multiple configuration bitstreams to program integrated circuits (ICs) such as programmable logic devices, thereby enabling the utilization of partially defective ICs. A user design is implemented two or more times, preferably utilizing different programmable resources as much as possible in each configuration bitstream. The resulting user configuration bitstreams are stored along with associated test bitstreams in a memory device, e.g., a programmable read-only memory (PROM). Under the control of a configuration control circuit or device, the test bitstreams are loaded into a partially defective IC and tested using an automated testing procedure. When a test bitstream is found that enables the associated user design to function correctly in the programmed IC, i.e.

Abstract: Methods and structures utilizing multiple configuration bitstreams to program integrated circuits (ICs) such as programmable logic devices (PLDs), thereby enabling the utilization of partially defective ICs. A user design is implemented two or more times, preferably utilizing different programmable resources as much as possible in each configuration bitstream. The resulting configuration bitstreams are stored in a memory device such as a programmable read-only memory (PROM). Under the control of a configuration control circuit or device, the various bitstreams are sequentially loaded into a partially defective IC and tested using an automated testing procedure. When a bitstream is found that enables the design to function correctly in the programmed IC, i.e., that avoids the defective programmable resources in the IC, the automated testing procedure terminates, and the programmed IC begins to function according to the user design as determined by the last programmed bitstream.

Abstract: Structures and methods that can be used to reduce power consumption in programmable logic devices (PLDs). Varying delays on the input paths of a PLD lookup table (LUT) can cause the nodes within the LUT (including the LUT output signal) to change state several times each time the input signals change state. Therefore, a programmable logic block for a PLD is provided that registers the LUT input signals instead of, or in addition to, the LUT output signal. The delays on the input paths are equalized and “glitching” on the LUT nodes is greatly reduced or eliminated. Thus, power consumption is reduced. Methods are also provided of reducing power consumption in PLDs by replacing single-bit registers on LUT output signals with multi-bit registers on LUT input signals, or by including multi-bit input registers in addition to the single-bit output registers.

Abstract: Decryption keys used in decrypting encrypted configuration data for a programmable logic device are erased following decryption of encrypted configuration data. A self-erasing key memory delivers a decryption key to a programmable logic device and then automatically erases itself. The keys are then no longer available outside the programmable logic device.

Abstract: An FPGA includes a plurality of configurable logic elements, a configuration circuit, a decryption circuit, and a fingerprint element. The fingerprint element generates a fingerprint that is indicative of inherent manufacturing process variations unique to the FPGA. The fingerprint is used as a key for an encryption system that protects against illegal use and/or copying of configuration data. In some embodiments, the propagation delay of various circuit elements formed on the FPGA are used to generate the fingerprint. In one embodiment, the specific frequency of an oscillator is used to generate the fingerprint. In some embodiments, a ratio of measurable values may be used to generate the fingerprint. In other embodiments, differences in transistor threshold voltages are used to generate the fingerprint. In still other embodiments, variations in line widths are used to generate the fingerprint.

Abstract: Described are methods and systems for encrypting and decrypting configuration data for programmable logic devices. An encrypted bitstream of configuration data includes two or more portions, each of which may be encrypted using a different key. Prior to loading, the author of each portion calculates the byte count for his or her portion and loads the required decryption key and byte count into a key and count memory. The designs are then loaded together as a single bitstream. The PLD decrypts the first portions using the first password. At the start of the partial bitstream, configuration logic loads the count associated with the decryption key for the first portions into a decrementing counter. The counter then decrements for each byte decrypted, reaching a count of zero when the first portion is fully decrypted. The configuration logic then selects the subsequent decryption key and associated count for the next portion of the bitstream.

Abstract: A circuit board includes a large scale logic device and at least one outrigger device wherein signals having a transmission delay budget that exceed a threshold value are produced to the outrigger device for coupling to circuit devices of the circuit board that are external to the large scale logic device. One embodiment of the invention comprises a plurality of outrigger devices that communicate with the large scale logic device by way of parallel data buses, as well as multi-gigabit transceiver data lines. Logic within the outrigger devices is generally limited to signal routing and transmission logic. The large scale logic device further comprises logic to transmit and receive signals to and from the outrigger devices in a way that is transparent to internal logic of the large scale logic device.

Abstract: Described are programmable logic devices that decrypt proprietary configuration data using on-chip decryption keys. The keys are stored in a key memory that can be operated in a secure mode or a non-secure mode. The non-secure mode allows the decryption keys to be read or written freely; the secure mode bars read and write access to the decryption keys. The programmable logic device supports secure and non-secure modes on a key-by-key basis, allowing users to write, verify, and erase individual keys without affecting others.

Abstract: An integrated circuit (IC) with a supervisory control circuit is disclosed. In various embodiments, the IC includes a plurality of configurable logic resources and interconnection circuitry. A first interface circuit is coupled to a set of interface ports that are coupled to the interconnection circuitry, and a second interface circuit is coupled to the device management resources. A control store is configured with control codes for accessing the device management resources. Responsive to a command received via the first interface circuit, a control circuit is configured to fetch selected control codes from the control store, execute the control codes, and access a selected device management resource via the second interface circuit.

Abstract: A method and apparatus that uses device defects as an identifier. Data is written to memory of an integrated circuit. Defects are identified based upon the writing of the data. An identifier for the IC is then derived using the identification of the defects.