Altera Corporation

Hyun Mo Yi

Vikram Santurkar

David Lewis

Martin Langhammer

Keone Streicher

Yi-Wen Lin

Suleyman Sirri Demirsoy

Paul Leventis

Ketan H Zaveri

Michael Chan

Christopher F Lane

Volker Mauer

Henry Y Lui

Chris Lane

Wai-Bor Leung

Quyen Doan

Andy Louie Lee

David Edward Jefferson

Brian D Johnson

David Cashman

Giles V Powell

Triet M Nguyen

Ravi Thiruveedhula

Configurable specialized processing blocks, such as DSP blocks, are described that implement fixed and floating-point functionality in a single mixed architecture on a programmable device. The described architecture reduces the need to construct floating-point functions outside the configurable specialized processing block, thereby minimizing hardware cost and area. The disclosed architecture also introduces pipelining into the DSP block in order to ensure the floating-point multiplication and addition functions remain in synchronicity, thereby increasing the maximum frequency at which the DSP block can operate. Moreover, the disclosed architecture includes logic circuitry to support floating-point exception handling.

Programmable device implementing fixed and floating point functionality in a mixed architecture

Digital signal processing ('DSP') circuit blocks are provided that can more easily work together to perform larger (e.g., more complex and/or more arithmetically precise) DSP operations if desired. These DSP blocks may also include redundancy circuitry that facilitates stitching together multiple such blocks despite an inability to use some block (e.g., because of a circuit defect). Systolic registers may be included at various points in the DSP blocks to facilitate use of the blocks to implement systolic form, finite-impulse-response ('FIR'), digital filters.

Modular digital signal processing circuitry with optionally usable, dedicated connections between modules of the circuitry

Digital signal processing ('DSP') block circuitry on an integrated circuit ('IC') is adapted for use (e.g., in multiple instances of the DSP block circuitry on the IC) for implementing finite-impulse-response (&#x201c;FIR&#x201d;) digital filters in systolic form. Each DSP block may include (1) first and second multiplier circuitry and (2) adder circuitry for adding (a) outputs of the multipliers and (b) signals chained in from a first other instance of the DSP block circuitry. Systolic delay circuitry is provided for either the outputs of the first multiplier (upstream from the adder) or at least one of the sets of inputs to the first multiplier. Additional systolic delay circuitry is provided for outputs of the adder, which are chained out to a second other instance of the DSP block circuitry.

Digital signal processing circuit blocks with support for systolic finite-impulse-response digital filtering

An embodiment of the present invention provides a programmable logic device ('PLD') including a redundancy architecture adapted to selective route signals via first or second staggered vertical lines. Other embodiments provide configuration logic and programs for determining routing selections. Other embodiments provide proximate grouping of vertical lines driven from a same row. Other embodiments provide definition of spare row locations once defective row locations are known.

Redundancy structures and methods in a programmable logic device

Techniques are provided for calibrating on-chip termination impedances on integrated circuits. An on-chip termination (OCT) calibration circuit generates calibration codes that selectively control the conductive states of a set of transistors coupled in parallel. The OCT calibration circuit selects a calibration code that causes the impedance of the transistors to be near a matching impedance. The selected calibration code controls an on-chip termination impedance at a pin. According to some embodiments, the OCT calibration circuit compares a signal from the transistors to two or more reference signals to improve the tolerance range of the calibrated on-chip termination impedance. According to other embodiments, the OCT calibration circuit selects a calibration code based on a signal from the transistors after an extra transistor is turned on by a control signal. The control signal is not used to control the on-chip termination impedance.

Techniques for providing calibrated on-chip termination impedance

Techniques are provided for controlling on-chip termination (OCT) impedance using OCT calibration blocks that serially transmit OCT control signals to input/output (IO) blocks. The OCT control signals are serially transmitted through a shared conductor. An OCT calibration block can transmit OCT control signals to one or multiple IO blocks. The IO blocks can be programmed to select OCT control signals from one of the calibration blocks. Enable signals enable one or more of the IO blocks to receive the selected OCT control signals. The OCT control signals are used to control the on-chip termination impedance at one or more IO buffers.

Techniques for serially transmitting on-chip termination control signals

An on-chip termination (OCT) calibration circuit includes one or more transistors coupled between a first terminal and a supply voltage, one or more transistors coupled between the first terminal and a low voltage, and a feedback loop circuit. The feedback loop circuit compares a signal from the first terminal to first and second reference signals to generate a first calibration code that controls conductive states of the one or more transistors coupled between the first terminal and the supply voltage and a second calibration code that controls conductive states of the one or more transistors coupled between the first terminal and the low voltage. The OCT calibration circuit controls an on-chip termination impedance at a pin using the first calibration code and the second calibration code.

A level conversion architecture that accommodates signals traveling between logic blocks operating at corresponding voltage levels is provided. The architecture includes pass gates connected in series between the logic blocks. One of the gates of the pass gates is supplied with a selectable gate voltage supply. The selectable gate voltage supply is selected from a plurality of voltages based on a configuration random access memory (CRAM) setting. In one embodiment, a half latch is connected to one of the pass gates. In this embodiment, the half latch is part of a feedback loop to minimize power leakage of a logic element in one of the logic blocks. A method for managing power consumption and providing voltage level conversion between regions of an integrated circuit is also provided.

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Mountain View, CA, United States of America

Hyun Mo Yi