Reference Source And Temperature Detection Module Design

In this work, the reference source and temperature detection circuit are designed for DTV Tuner. The RF receiver is SoC(System on Chip),which includes three types of circuit system:RF, analog and digital circuits. The requirement of different type circuits to the reference varies, power fluctuations impact larger on the system. As result of the introduction of the RF circuit, need to lower output noise. Reference and temperature detection circuit design and exploration for these new problems.First, the article describes the design of bandgap voltage reference. To receiver characteristics, a detailed analysis of temperature coefficient, output noise and power supply rejection of bandgap, sort out a solution to meet the design requirements, with a high power supply rejection and low output noise characteristics, the temperature coefficient is less than15.48ppm/℃, the VDD of2.1～3.3V DC power supply rejection smaller than-79.8dB, the VDD of1.8V DC power supply rejection is-60dB.Less than16.93μVrms integral noise from100Hz to100kHz range.Then, the design of the voltage to current converter. The circuit uses6bits digital signal control on-chip resistor array, the output current accuracy of7.8%o. Add the common-source common-gate transistors, get a high power supply rejection, in a simple circuit structure and its DC power supply rejection is-95.3dB.Finally, the design of temperature sensing circuitry. The temperature sensing range is-45℃-125℃, the temperature slope of the output voltage5.2mV/℃.