Biography
Enrollment Date: 2009
Graduation Date：2012
Degree：M.S.
Defense Date：2012.05.25
Advisors：Liji Wu
Department：Institute of Microelectronics，Tsinghua University
Title of Dissertation/Thesis：Key IP Cores of Power Management and Temperature Sensing Design and Implementation for Control Chip in TPMS
Abstract:
Tire Pressure Monitoring System (TPMS) is an important branch of the field of automotive electronics. With the development of city development and the popularization of cars, car safety is a universal concern for transportation field in the world. The traffic accident is often due to tire’s pressure decreases and the car body out of balance. If an accident occurs while the automobile at high speed, it is bound to cause irreparable damage to the automobile body and the driver. Therefore, in the running process of the automobile, how the driver can know the tire pressure and temperature is the issue what automotive electronics manufacturers need to take into consideration. Therefore, the Tire Pressure Monitoring system is presented to implement the function, and it monitors the air pressure and the tire temperature in real-time. If the pressure and temperature value abnormity, TPMS will informs the driver to take measures through the warning information in time.
The foreign semiconductor manufacturers have forestalled the global and domestic automotive semiconductor markets. Designing and manufacturing in China with independent intellectual property rights of automobile electronic chips is of great significance, which is not only for the special field of chip design capability, but also on the related technology exploration.
Based on the 0.35 micron CMOS auto electronic technology of Shanghai Advanced Semiconductor Manufacturing Limited Corporation (ASMC), this thesis makes chip level research and development in the light of key IP cores of control chip in TPMS SoC. The inner monitoring module of TPMS is designed as a SoC. This thesis focus on power management IP core LDO and CMOS temperature sensor of SoC. They are implemented with layout and taped-out. The LDO dies are tested and verified in the light of function. The CMOS temperature sensor was simulated and verified.
All of the IP cores in the SoC need a DC power of 3V±5% voltage including instrumentation amplifier, MCU, analog-digital converter, 125 KHz low frequency wakeup module, temperature sensor. The SoC offers power for MEMS pressure sensor. LDO offers different specification for each IP core and it can be compromised deliberately. Firstly, the stability must be considered when we design a LDO. It must offer sufficient current for load circuit and have fast transient response. Based on the analysis in principle, this thesis presents a LDO circuit structure and a temperature sensor structure meeting the systemic application requirements. The load current can be up to 60 mA and PSRR up to -67.5dB@2.402Hz. The phase margin is up to 70.83 degrees typically which makes the LDO loop circuit stable. The CMOS temperature sensor is designed to work between -45℃~125℃. According to the simulation data, the thesis got the resolution and maximum error with different power voltage and the average power in phase of data measurement. It has been taped-out after simulation and layout design, which meets the specification requirements.