Lattice Semiconductor Corporation

Ravindar Mohan Lall

Om P Agrawal

Wei Han

David Lee Rutledge

Robert Beverly Lefferts

Nathan Green

Tom Gustafson

James Lawrence Gorecki

Satwant Singh

Fulong Zhang

Moshe Agam

Ming Hui Ding

Sreepada Hegade

Trent Whitten

Mose Wahlstrom

Joel Coplen

Dale A Potter

Gordon Hands

John Jiang

Kazi Habib

Various techniques are provided to implement fast boot for programmable logic devices (PLDs). In one example, a method includes receiving configuration data associated with a PLD. The PLD includes an array of configuration memory cells including logic block memory cells and input/output (I/O) block memory cells associated with the PLD's logic fabric and I/O fabric, respectively. The method further includes programming a subset of the I/O block memory cells with the configuration data, and providing a wakeup signal to activate functionality associated with a portion of the I/O fabric. The method further includes programming remaining configuration memory cells of the array with the configuration data, where the remaining configuration memory cells include at least a subset of the logic block memory cells. The method further includes providing a wakeup signal to activate functionality associated with at least a portion of the logic fabric. Related systems and devices are provided.

Fast boot systems and methods for programmable logic devices

In one embodiment, a circuit such as a comparator circuit includes a differential stage adapted to receive a differential input signal and first and second diodes coupled to the differential stage. The first and second diodes are adapted to selectively switch on and off to provide a differential output signal at first and second differential output nodes in response to the differential input signal. The circuit may include an output stage coupled to the first and second diodes at the first and second differential output nodes, with the output stage adapted to convert the differential output signal to a single ended output signal. The circuit may also include a current source adapted to selectively provide a reference current to the first or second diode in an off state to reduce voltage swing of the first or second diode between the off and an on state.

Comparator with jitter mitigation

In one example, a comparator circuit includes a differential stage adapted to receive a differential input signal. The comparator circuit includes first and second diodes coupled to the differential stage. The first and second diodes are adapted to selectively switch on and off to provide a differential output signal at first and second differential output nodes in response to the differential input signal. The comparator circuit includes a current steering circuit adapted to selectively provide a reference current from a current source to the first or second diode in an off state to reduce a voltage swing of the first or second diode between the off state and an on state. The comparator circuit includes an output stage coupled to the first and second diodes at the first and second differential output nodes. The output stage is adapted to convert the differential output signal to a single ended output signal.

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

Systems and methods disclosed herein provide temperature monitoring within an integrated circuit. For example, in accordance with an embodiment of the present invention, a bandgap reference circuit provides a reference voltage; a constant current generator provides a constant current; and a reference signal circuit receives the reference voltage and provides a reference signal having a selectable value based on the reference voltage. A bipolar diode receives the constant current and provides a sense signal, with a value of the sense signal corresponding approximately to a temperature value of the integrated circuit. A comparator receives the sense signal and the reference signal and provides a temperature sensor output signal.

Integrated circuit temperature sensor systems and methods

In one embodiment, a (negative-voltage) charge pump with one or more stages that receives a (high) input voltage and generates a higher-magnitude (negative) output voltage. Each stage has two capacitors for storing charges and two branches that alternate to transmit a higher-magnitude output voltage at every clock half cycle. Each branch has a PMOS transistor and a NMOS transistor. To reduce the effects of back body from the substrate, two transistors are constructed with three wells and two with four wells, where the number of wells per device is dependent upon the substrate type used.

Charge pump with four-well transistors

A programmable logic device in accordance with an embodiment of the invention includes configurable logic blocks, embedded random access memory (RAM) blocks, and input/output blocks adapted to transfer information into or out of the programmable logic device. An interconnect architecture is adapted to route information among the configurable logic blocks, embedded RAM blocks, and input/output blocks within the programmable logic device. An interface block is provided that couples an embedded RAM block and an input/output block but not a logic block to the interconnect architecture.

Interface block architectures

In accordance with an embodiment of the present invention, a programmable logic device includes a memory adapted to store information in the programmable logic device, an input/output circuit adapted to transfer information into or out of the programmable logic device, and an interconnect architecture adapted to route information within the programmable logic device. An interface circuit is provided to couple the memory and the input/output circuit to the interconnect architecture.

A wide input programmable logic system includes a plurality of logic gates that receive a plurality of row driver signals and memory cell outputs to generate a plurality of logical NOR or NAND outputs for their respective one of said row driver signals and memory cell outputs that are programmed. At least one additional stage of logic gates having a plurality of logical NAND or NOR gates receive the respective logical NOR or NAND outputs and generate a plurality of respective logical NAND or NOR outputs. At least one respective logical NOR or NAND gate receives the respective plurality of logical NAND or NOR outputs and generates an output term. The memory cell may include an electrically erasable non-volatile memory cell having a storage cell that stores a logical value and a select transistor coupled to the storage cell. The select transistor is controlled by a first control signal, with the select transistor isolating the storage cell during editing upon receipt of an asserted state of the first control signal. A latch is coupled to the select transistor and controlled by a latch control signal to provide an output corresponding to the logical value stored in the storage cell. Respective timing of the first control signal and the latch control signal results in zero power dissipated by the electrically erasable non-volatile memory cell.

Memory cell

Wide input programmable logic system and method

A CMOS Schmitt Trigger circuit design provides a relatively high speed device having a tight, substantially monotonic hysteresis characteristic which is substantially independent of fabrication process parameters and can be used with relatively wide power supply designs, including operating a relatively low Vcc. Tight trip point variation is maintained in conjunction with process, voltage, and temperature changes. The circuit is adaptable for forming an integrated circuit buffer element.

High speed Schmitt Trigger with low supply voltage

A sense amplifier is provided that mitigates the effect of threshold voltage mismatch within the sense amplifier. The sense amplifier has an inverter pair coupled to the input terminals, with a resistive element coupled across output terminals of the inverter pair. Inverter gain stages following the inverter pair are coupled to a current limiting circuit to monitor and limit the current flowing through the inverter gain stage immediately following the inverter pair. The current limiting circuit allows the sense amplifier to be biased such that speed is improved while limiting power dissipation to acceptable levels, even under undesirable process, temperature, and power supply variations.

Sense amplifier systems and methods

A high voltage CMOS switch circuit having an arrangement of device connections such that the individual transistor devices are substantially the same size, improving performance while reducing size and providing breakdown protection. The circuit switches a high voltage to the output based on a low voltage input. The circuit is ratio-less and self-biased, capable of operating a very low supply voltage compared to the state of the art.

High voltage CMOS switch

An embodiment of a pumped substrate system includes an oscillator, capacitive pump, comparing circuit, and a level shifter. The level shifter is coupled between the substrate and the positive input lead of the comparator and shifts the voltage level present on the substrate by a voltage Vbg. The comparator compares ground potential to the shifted substrate voltage. The oscillator, capacitive pump and comparing circuit form a negative feedback loop which operates to maintain the substrate voltage substantially equal to -Vbg. In one embodiment, the level shifter includes a band gap reference.

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Portland, OR, United States of America

Ravindar Mohan Lall