Quicklogic Corporation

Ket-Chong Yap

Wilma Waiman Shiao

Andrew K Chan

James M Apland

Senani Gunaratna

Stephen U Yao

Pinaki Chakrabarti

David D Eaton

Kevin K Yee

Vishnu A Patil

E Thomas Hart

Neal A Palmer

Michael W Dini

Panawalge S N Gunaratna

SunilKumar G Mudunuri

Lalit Narain Sharma

Darwin D Q Samson

A programmable logic device uses power island based design partitioning. Each power islands includes a plurality of programmable logic cells and a programmable routing network configurable to interconnect the plurality of programmable logic cells and configurable to interconnect with at least one other power island. When a power island is in an OFF state, the programmable logic cells within the power island are powered OFF. Feed-through routing connectors in the power island, however, may be statically or dynamically powered ON independently of the powered OFF state of the power island.

Switchable power islands having configurably on routing paths

An integrated circuit includes a programmable logic device, a dedicated device, and an interface circuit between the two. The interface circuit can be easily modified to accommodate the different interface I/O demands of various dedicated devices that may be embedded into the integrated circuit. In one embodiment, the interface circuit may be implemented using a plurality of mask programmable uni-directional interface buffer circuits. The direction of any desired number of the interface buffer circuits can be reversed based on the needs of a desired dedicated device by re-routing the conductors in the interface buffer circuits in a single metal layer of the integrated circuit. In another embodiment, the interface circuit may be implemented using a hardware configurable bi-directional interface buffer circuit.

Adjustable interface buffer circuit between a programmable logic device and a dedicated device

Testing of combinatorial logic in a programmable device is provided by routing input and/or output test values as signals from and back to dedicated logic through programming circuitry in programmable logic. Some embodiments of the present invention provide for a method for testing functional logic block of an application-specific standard product (ASSP) in a programmable logic device, the method comprising: storing an input value into a register; passing the input value from the register to combinatorial logic; producing an output value from the combinatorial logic; passing the output value from the combinatorial logic to the register; saving the output value in the register; and reading the output value out of the register.

FPGA programming structure for ATPG test coverage

An apparatus and method of reducing power consumption across a switch, such as an unprogrammed antifuse, is provided. The invention applies to antifuses, other switches such as transistor based switches, (e.g., FLASH, EEPROM and/or SRAM) and other devices exhibiting a leakage current, especially during a sleep or stand-by mode. During a sleep mode, such switches or other devices may be uncoupled from signals driving the switches, then terminals of each switch may be coupled to a common potential or allowed to float to a common potential thereby eliminating or reducing leakage currents through the switches.

Low power mode

A programmable circuit, such as a field programmable gate array, and a dedicated device, such as an ASIC type device, are coupled together with an antifuse based interface on a single integrated circuit. A configurable non-volatile memory that communicates with the dedicated device is also located on the integrated circuit. The platform for the programmable circuit is one half of an existing programmable circuit, which eliminates the need to engineer the programmable circuit. The programmable circuit includes a clock network that receives clock signals from clock terminals as well as from a clock network in the dedicated device. The interface between the dedicated device and programmable circuit includes a number of conductors with buffers with testing circuitry. The testing circuitry includes a PMOS test transistor and a NMOS test transistor which permits testing of the buffers without programming the antifuses coupled to the conductors. The input/output terminals around the periphery and in the interface between the programmable circuit and dedicated device are tested using JTAG registers. The path of the test signal through the JTAG registers is selectable to pass around the periphery of both the programmable and dedicated devices or through the interface and around the periphery of only one of the programmable and dedicated devices.

Programmable antifuse interfacing a programmable logic and a dedicated device

In accordance with the invention, a serializer/deserializer core of a field programmable gate array includes a channel clock and a data channel. The data channel can serialize and deserialize data in two modes. In the first mode, an embedded clock signal is recovered from the data. In the second mode, a clock signal is provided by the channel clock. A selection signal determines in which mode each of the data channels in the serializer/deserializer core operates. An stair-step clock generator generates a series of rising edge signals used to serialize and deserialize data. The number of bits serialized and deserialized is determined by the control signals to a set of multiplexers in the stair-step clock generator which determine how many registers in the stair-step clock generator are activated.

Serializer/deserializer embedded in a programmable device

A random access memory (RAM) device includes a buffer in the memory cell to isolate the latching circuit from the read bit line. Consequently, read disturb errors caused by capacitive loading on the read bit line are avoided. Further, the precharge requirements on the write bit line are simplified because the buffer permits optimization of the latching circuit in the memory cell. The RAM device includes a precharge circuit that precharges the write bit line to a ground reference voltage prior to performing write operations. By precharging the write bit line to ground reference voltage, write disturb problems caused by capacitive loading on the write bit line are avoided. Further, by coupling the write bit line to ground reference voltage, little or no power is consumed by precharging the write bit line.

Growing community of inventors

San Ramon, CA, United States of America

Ket-Chong Yap