Research On Chip Temperature Distribution Measurement Based On FPGA And Engineering Application

Field programmable gate array(FPGA)has the advantages of fast operation speed,strong flexibility and low power consumption,and has been widely used in communication,image,information processing and other fields.It is also widely used in the research of FPGA thermal characteristics to build a ring oscillator as a temperature sensor in the FPGA.The development of semiconductor process technology has improved chip integration,and the increase in chip operating frequency has also increased chip power consumption.The combination of the two causes the temperature of the chip to increase rapidly,which greatly reduces the reliability of the chip.Therefore,based on the FPGA development platform,it is important to monitor the operating temperature of the chip and master the temperature distribution of the chip.Based on FPGA embedded ring oscillator,this paper proposes a method based on FPGA platform to measure the temperature distribution of external chip.We mainly use the FPGA embedded ring oscillator as a temperature sensor and build an intelligent temperature-sensing network to dynamically measure the temperature distribution of the tested chip.Compared with infrared measurement,it is simple,non-destructive,and has a wide range of applications,meeting the industrial needs of quickly measuring chip temperature distribution.The specific content includes the following aspects:1.The construction of a temperature sensing network.It is mainly based on the internal logic resources of FPGA to form an embedded ring oscillator and build an intelligent temperature-sensing network,which can dynamically measure the temperature distribution of the chip.The temperature sensor converts the temperature signal into a pulse signal through a ring oscillator.The frequency of the pulse signal is linear with temperature.The counter converts the output frequency of the ring oscillator into a digital signal through a reference clock,and then transmits it to the computer through the serial port UART.2.Optimization of measurement accuracy and verification of results.In order to reduce the loss of heat transfer when the tested chip is attached to the FPGA,it is necessary to reduce the package thickness of the FPGA by laser.Secondly,the Tcl language is used to misplace the position of the temperature sensor and measure it multiple times to improve the measurement accuracy.Finally,the temperature distribution map of the tested chip is established and displayed in the host computer.The temperature profile measured by the temperature sensor is compared with the temperature profile of the infrared measurement to verify the correctness of the method.3.The engineering application of the thermal resistance tester system.The uart communication module with the host computer based on the FPGA is designed.Based on VS2010 as the development platform,two user-friendly interfaces were designed.A thermal resistance tester software that integrates a 3-channel LED with a 1-channel VDMOS to simultaneously measure the thermal resistance of a three-terminal device or the thermal resistance of three different two-terminal devices.The other is the thermal resistance tester software of VDMOS under external pulse power.The thermal resistance of VDMOS is cyclically measured under the condition of applied pulse power.The relationship between thermal resistance value and pulse width,duty cycle and steady-state thermal resistance is studied.After complete measurement a graph of thermal resistance values varying with pulse width at different duty cycles is drawn.