Lattice Semiconductor Corporation

Mose Wahlstrom

Wei Han

Warren Juenemann

Barry Britton

Zheng Chen

Ravindar Mohan Lall

Trent Whitten

Yoshita Yerramilli

Nathan Green

Eric Lee

Glenn Thomas O'Rourke

Various techniques are provided to flexibly update data fields stored in multi-bit registers. In one example, a method of updating a control register within an integrated circuit includes storing a plurality of initial bit values in the control register within the integrated circuit. The method also includes receiving a data set comprising one or more corrective bit values and one or more non-corrective bit values. The method also includes performing a logic operation on the received data set and the initial bit values to provide updated bit values. The method also includes replacing the initial bit values with the updated bit values in the control register.

Flexible updating of multi-bit registers

A programmable logic device (PLD) is disclosed that includes a non-volatile memory; a shadow register; and a data shift register (DSR) configurable to receive control information from an external programming tool, wherein the DSR is configured to shift the control information into the shadow register if the PLD is in a first programming mode, the PLD being configurable to operate in the first programming mode using the control information stored in the shadow register without the control information being stored in the non-volatile memory.

Safe programming of key information into non-volatile memory for a programmable logic device

Various techniques are provided for determining interface characteristics of external devices. In one example, a method of configuring a programmable logic device (PLD) with configuration data stored in one or more external memory devices includes reading by the PLD an interface setup command in a bitstream from an external memory device through a configuration port of the PLD while operating the configuration port in accordance with a first set of interface characteristics. The method also includes adjusting by the PLD the configuration port to operate in accordance with a second set of interface characteristics identified by the interface setup command. The method also includes reading by the PLD configuration data in the bitstream from the external memory device through the configuration port while operating the configuration port in accordance with the second set of interface characteristics. The method also includes programming a configuration memory of the PLD with the configuration data.

Reading an external memory device to determine its interface characteristics for configuring a programmable logic device

An on-chip temperature sensor for an integrated circuit includes in one embodiment a voltage/current source circuit that provides a reference voltage and a current. A sense signal circuit receives the current of the voltage/current source circuit and provides a sense signal corresponding to the temperature of the integrated circuit. A reference signal receives the reference voltage of the voltage/current source circuit and provides a reference signal having a selectable value. A comparator compares the sense signal of the sense signal circuit to the selectable reference signal of the reference signal circuit and provides a temperature sensor output signal.

On-chip temperature sensor for an integrated circuit

Methods and devices are disclosed herein to provide improved techniques for securing configuration data stored in non-volatile memories of programmable logic devices. For example, in accordance with an embodiment of the present invention, a programmable logic device includes a non-volatile memory adapted to store a plurality of configuration data. A plurality of security fuses are adapted to store a plurality of logic states. Control logic is adapted to selectively secure the configuration data within the non-volatile memory based on the logic states stored in the plurality of security fuses.

Selective programming of non-volatile memory facilitated by security fuses

Methods are described herein, for improving the accuracy of propagation delay measurements of programmable electronic devices in a production environment. In one method, a built-in self-test is implemented by configuring an oscillator and a counter connected to each other within the PLD. The oscillator is enabled to oscillate for a pre-determined length of time and to cause the counter to count up at the end of each cycle of oscillation. The counter reading is correlated to an accurate propagation delay measurement by using a previously generated counter-delay correlation curve. In other methods, the counter is built outside of the logic of the PLD. Methods are described for adapting typical output macro cells to provide combinatorial feedback for configuring oscillators within PLDs without such capabilities.

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Aloha, OR, United States of America

Mose Wahlstrom