Xilinx, Inc.

Sambanova Systems, Inc.

Uma E Durairajan

Subodh Kumar

Thomas Alan Ziaja

Dinesh Rajasavari Amirtharaj

Michelle Zeng

James M Simkins

Weiguang Lu

James E Ogden

Hsiao H Chen

Matthew H Klein

Amitava Majumdar

Kumar Rahul

Adam Elkins

Thomas H Strader

Karthy Rajasekharan

Ghazaleh Mirjafari

Kumar Subodh

An integrated circuit (IC) includes first and scan latches that are enabled to load data during a first part of a clock period. A clocking circuit outputs latch clocks with one latch clock driven to an active state during a second part of the clock period dependent on a first address input. A set of storage elements have inputs coupled to the output of the first scan latch and are respectively coupled to a latch clock to load data during a time that their respective latch clock is in an active state. A selector circuit is coupled to outputs of the first set of storage elements and outputs a value from one output based on a second address input. The second scan latch then loads data from the selector's output during the first part of the input clock period.

Single 'A' latch with an array of “B” latches

Testability of memory on integrated circuits is improved by connecting storage elements like latches in memory to scan chains and configuring memory for scan dump. The use of latches and similar compact storage elements to form scannable memory can extend the testability of high-density memory circuits on complex integrated circuits operable at high clock speeds. A scannable memory architecture includes an input buffer with active low buffer latches, and an array of active high storage latches, operated in coordination to enable incorporation of the memory into scan chains for ATPG/TT and scan dump testing modes.

Method and circuit for row scannable latch array

Method and circuit for scan dump of latch array

In an example, a memory circuit in a programmable integrated circuit (IC) includes: a control port and a clock port; a configurable random access memory (RAM) having a control input and a clock input; input multiplexer logic coupled to the control input and the clock input; and a state machine coupled to the input multiplexer logic and configuration logic of the programmable IC, the state machine configured to: in response to being enabled by the configuration logic, control the input multiplexer logic to switch a connection of the control input from the control port to the state machine and, subsequently, switch a connection of the clock input from the clock port to a configuration clock source; and in response to being disabled by the configuration logic, control the input multiplexer logic to switch the connection of the clock input from the configuration clock source to the clock port and, subsequently, switch the connection of the control input from the state machine to the control port.

Implementing robust readback capture in a programmable integrated circuit

Methods and apparatus are described for providing and operating an efficient infrastructure to implement a built-in clock stop and scan dump (CSSD) scheme for fabric blocks, such as block random access memory (BRAM), UltraRAM (URAM), digital signal processing (DSP) blocks, configurable logic elements (CLEs), and the like. This is a very useful feature for system debug and can also be applied for emulation use cases (e.g., FPGA emulation). This scheme can be applied to any tiled architecture that has highly repetitive blocks. The infrastructure may include a DFx controller shared across multiple tiled blocks with some distributed logic in each block, in an effort to minimize or at least reduce area overhead. The infrastructure may also minimize or at least reduce utilization of fabric resources in an effort to ensure the least perturbation of the original design, such that the design issues being debugged can be easily reproduced.

Efficient system debug infrastructure for tiled architecture

Circuits and methods for initializing a memory. Each row of the memory includes data bits and associated parity bits. A write buffer contains bit values for initializing the memory, and a control circuit performs a first set of write operations that write values from the write buffer to the data bits of the memory without writing values to the associated parity bits. The write buffer performs a second set of write operations that write values from the write buffer to the parity bits associated with the data bits without writing data to the data bits.

Memory initialization

An embodiment of a memory module is disclosed. This memory module is a configurable hard macro. A portion of this memory module includes a data input multiplexer coupled to select between cascaded data and direct/bused data. Such portion further includes, a memory coupled to receive output from the data input multiplexer for storage therein, and a register input multiplexer coupled to select between read data from the memory and the cascaded data. This memory module further includes: a register coupled to receive output from the register input multiplexer, a latch/register mode multiplexer coupled to select between the read data from the memory and registered data from the register, and a data output multiplexer coupled to select between the cascaded data and output from the latch/register mode multiplexer to provide output data.

Configurable embedded memory system

An apparatus relates generally to a clock generator is disclosed. The clock generator is coupled to receive an input clock signal and further coupled to provide an output clock signal. An address and control register is coupled to receive an address signal and the output clock signal. An access generator is coupled to receive the output clock signal. The clock generator includes: an input node coupled to receive the input clock signal; at least one pulse generator coupled to the input node to receive the input clock signal and further coupled to provide a clock control signal; and a control gate coupled to the input node to receive the input signal and further coupled to the at least one pulse generator to receive the clock control signal. The clock control signal is provided in a non-toggling state for a high-frequency mode and in a toggling state for a low-frequency mode.

Bimodal clock generator

An integrated circuit and method for using a synchronous reset pulse to reset a circuitry comprising a plurality of clock domains are disclosed. For example, the method of the present disclosure provides a reset signal that is synched to one clock, takes the synchronous signal and resets circuits in a plurality of clock domains. In order to reset a portion of the circuit which is in a particular clock domain, the reset needs to be synchronized to the clock of the particular domain.

Growing community of inventors

San Jose, CA, United States of America

Uma E Durairajan