Low Output, Low Temperature Coefficient, A Wide Temperature Range, The Bandgap Reference Voltage Source Of Design And Research

With the development of semiconductor process and circuits design methodology, Analog integrated circuit improved greatly in recent years. There is a challenge to the performance of circuits. Also with the popular use of electronic system powered by battery, low power system becomes more important. Analog IC includes linear and nonlinear circuits. For example, amplifier, comparator and oscillator. Reference circuits is a building block which is absolutely necessarily in analog IC, and it's precision has more effects on the whole system.Bandgap reference voltages are important analog circuit blocks. It can provide a nearly constant reference voltage which is stabilized over process , power supply and temperature variation. It makes the bandgap reference voltage be used extensively in Analog to Digital Converter(A/D C), Digital to Analog Converter(D/A C), Power management circuits and memories. At the same time, bandgap reference voltage is simple in structure and more reliable, it could be implemented in standard CMOS process ,so it's suitable for mass production. At present, the bandgap reference voltage has been the most popular reference voltage generator in CMOS integrated circuits.The output voltage of conventional bandgap reference voltage circuit is 1.26v which is nearly equal to the bandgap voltage of silicon, so the circuit is named bandgap reference voltage. But the fixed output voltage limits the application of the bandgap reference voltage and the operation with low power supply. In mis thesis ,we proposed a new structure of the circuit which could operate with lower power supply(lower than 2v) and provide a lower output reference voltage(lower than 1v) in the temperature range of -40℃-140℃ with low temperature coefficient according to the request of the CMOS Image Sensor.