Kosta Luria

Ratiometric BJT-based thermal sensor in 32nm and 22nm technologies

Thermal sensors are used in modern microprocessors to provide information for: 1) throttling at the maximum temperature of operation, and 2) fan regulation at temperatures down to 50°C. Todays microprocessors are thermally limited in many applications, so accurate temperature readings are essential in order to maximize performance. There are fairly large thermal gradients across the core, which vary for different instructions, so it is necessary to position thermal sensors near hot-spots. In addition, the locations of the hot-spots may not be predictable during the design phase. Thus it is necessary for hot-spot sensors to be small enough to be moved late in the design cycle or even after first Silicon.

Miniaturized BJT-Based Thermal Sensor for Microprocessors in 32- and 22-nm Technologies

A thermal sensor is proposed for microprocessors, which compares the BJT voltage to a reference by converting both voltages to frequency and dividing the frequencies to result in a digital number. The sensor has an rms resolution of ±0.2C and an area of 0.02 mm2 at the 32-nm process node and 0.006 mm2 at 22 nm, including all digital processing circuitry. The conversion rate is between 2-20 kS/s, which enables it to capture fast transients on the CPU. It consumes 3.8/1.4 mW at 32/22 nm from an unregulated 1.4-V supply. The combination of speed, low power, and area make this sensor appropriate to measure hot-spots in microprocessors.

A Fully Integrated Multi-CPU, Processor Graphics, and Memory Controller 32-nm Processor

This paper describes the second-generation Intel Core processor, a 32-nm monolithic die integrating four IA cores, a processor graphics, and a memory controller. Special attention is given to the circuit design challenges associated with this kind of integration. The paper describes the chip floor plan, the power delivery network, energy conservation techniques, the clock generation and distribution, the on-die thermal sensors, and a novel debug port.

Miniaturized CMOS thermal sensor array for temperature gradient measurement in microprocessors

A miniaturized thermal sensor for use in Intels microprocessors has been demonstrated in a cutting-edge purely digital process. The circuit shows nearly linear frequency dependence with temperature of 45kHz/°C. The circuit occupies 3.75×l0⁻³ mm² and consumes a current of ~ 700uA, which makes it suitable to be placed in array on a microprocessor to measure thermal gradients across the die.

8.7 Dual-use low-drop-out regulator/power gate with linear and on-off conduction modes for microprocessor on-die supply voltages in 14nm

In recent generations of microprocessors, there has been an increase in the number and types of processors integrated on the same die. For example, in [1] several IA (Intel architecture) cores have been integrated on-chip with a graphics processor. Multi-core trends are expected to increase in future generations with different cores and units requiring varying supply voltages. As platform footprints are also required to decrease, this causes a unique challenge for voltage regulation. In [2], an on-die switching fully integrated voltage regulator (FIVR) was demonstrated, which presents a very good solution in many cases. However, the FIVR requires inductors, which may not always be available. In addition, it may be desirable to sub-divide some of the FIVR domains using power gates and/or linear voltage regulators, such as low-drop-out regulators (LDO). LDOs can be used to enable different units of the chip to operate at their optimal voltage levels, which could save power. For example, different types of cores often have significantly different minimum-Vcc levels in low-power mode. In addition, a core or graphics unit could enter a high-performance mode, where the voltage is ramped up to enable performance, while other cores are in sleep or low-power modes.

Dual-Mode Low-Drop-Out Regulator/Power Gate With Linear and On–Off Conduction for Microprocessor Core On-Die Supply Voltages in 14 nm

A dual-mode digital power gate (PG) and linear low-drop-out regulator (LDO) has been demonstrated in 14 nm. A modified flipped source follower driver circuit is used to minimize dI/dt droops. The LDO has a novel compensation method which utilizes capacitance multiplication and can drive a 1-7 μF load without any external compensation elements. This LDO exhibits high-current drive capability (3 A) at low-dropout voltages (<; 60 mV) and high-current efficiency (> 99%), making it suitable to drive a microprocessor core.

Evolution of thermal sensors in Intel processors from 90nm to 22nm

Thermal sensors are used in Intel processors in order to measure and regulate the chips temperature. This is useful to insure that the temperature does not exceed the reliability limit and also to optimize processor performance. Several sensors developed in Intel processes are reviewed and their evolution over different process generations is explained. The design tradeoffs and system requirements for these sensors are discussed.