by thermoelectric elements, Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat ; Power supply, e.g. Thermal sensors: integrated thermopile sensors; semiconductor-junction temperature sensors; proportional-to-absolute-temperature sensors (PTAT). Linearity is analyzed and a compensation strategy to improve it is developed. VPTAT is obtained via a simple analysis: type humidity sensor interface circuit with on-chip PTAT temperature sensor is shown in Figure 1. PTAT current sources are widely used to generate bias currents and as temperature sensor in temperature meas- urement systems. In the foregoing embodiments, the connection relationships of the entire circuit are established on the basis that the transistors Q1 and Q2 are PNP transistors. Features of LM35 Temperature Sensor It converts the temperature of an external sensor or its own temperature to an analog voltage output. The device is designed in IME platform through OpSIS, which enables interconnection of distributed PTAT … When the first preferred embodiment is incorporated to the second preferred embodiment, the sensing unit 22 can generate up to 23×27=210 types of circuit configurations, where the control signal has at least 10 bits. The main block of the chip consists of C-F converter, reference timer, PTAT temperature sensor and oscillator, counting logic, OTP memory and digital interface logic circuits. Since vertical PNP transistor in single n-well submicron process is prone to process variations, it impacts the accuracy of temperature sensor. 3B are schematic diagrams of first and second connection configurations respectively. Abstract: A temperature sensor used to compensate the crystal oscillator frequency instability of a real time clock (RTC) is proposed in this paper. The switch units 611, 621 and 631 are used for respectively interchanging connection relationships of input ends of the amplifiers 61, 62 and 63. In addition, no current flows through the two input ends of the amplifier 63 such that a current flows through R1 is equal to a current flows through R2 and a current flows through R3 is equal to a current flows through R4. Memory The switch unit interchanges connection relationships of the pair of circuit components according to the control signal generated by the control unit 21, so as to generate a fifth connection configuration and a sixth connection configuration. FIG. For example, A5/A4=8*(1+ΔA4), the amplifier 11 has a voltage offset Voffset(T) between its two input ends, where the Voffset(T) changes according to the absolute temperature T, M4/M3=1.5*(1+ΔM4), R10/R8=1+ΔR8, and R11/R9=1+ΔR9. They are usually thermistor devices. It converts the temperature of an external sensor or its own temperature to an analog voltage output. As the sensor will be used for temperature monitoring in an implant where the temperature range of interest is restricted, the errors due to non-linearity are small (Figure 3). a bias circuit, coupled to the first switch unit, for providing the bias voltage; and. The cabin temperature sensor is used for detecting the average air temperature in the cabin and for allowing an accurate reading; a small fan is used to lead sample air to the sensor. Silicon bandgap temperature sensor Last updated September 22, 2020. V out =V +*20−V −*20=20V in. 4B are schematic diagrams of third and fourth connection configurations respectively. The sixth connection configuration is that the gate of the transistor M2 is coupled to a drain of the transistor M2 and a drain of the M1 is coupled to the output end 227. a calculation unit, coupled to the sensing unit, for calculating a PTAT voltage value according to the first voltage value and the second voltage value. 4A, operation of the sensing unit 22 is described below. In the range from − 55 ° C to 155 ° C, the worst deviation of the CTAT and PTAT temperature sensors is measured to be − 3.75 ° C to + 3.34 ° C and − 3.73 ° C to + 3.85 ° C, respectively. The main block of the chip consists of C-F converter, reference timer, PTAT temperature sensor and oscillator, counting logic, OTP memory and digital interface logic circuits. 7. The switch units 612, 622 and 632 are used for respectively interchanging connection relationships of the pair of internal circuit components having the matching relationship in the amplifiers 61, 62 and 63. The reference oscillator is biased by a current whose temperature dependency is complementary to the proportional to absolute temperature (PTAT) current. The temperature sensors include an ambient temperature sensor, a cabin temperature sensor, an evaporator temperature sensor, and a water temperature sensor. FIG. The amplifier has a first input end, a second input end, and an output end. For ex: In the output image, room temperature is approximately 250C. That is, when the amplifiers 61 and 62 wish to interchange connection configurations as illustrated in FIG. Temperature is the 8 pixel temperature values (as we are using 1x8 thermal sensor). Can someone enlighten me? A proportional to absolute temperature (PTAT) sensor, comprising: a control unit, for generating a control signal; a sensing unit, coupled to the control unit comprising: an amplifier having a first input end, a second input end, and an output end; a first transistor having a first collector, a first emitter, and a first base, wherein the first emitter is coupled to the first input end of the amplifier; a second transistor having a second collector, a second emitter, and a second base, wherein the second collector is coupled to the first collector, and the second emitter is coupled to the second input end of the amplifier; a first switch unit, coupled to the output end of the amplifier, the first transistor, and the second transistor, wherein the first switch connects the output end of the amplifier to the first transistor in a second connection configuration, or the first switch connects the output end of the amplifier to the second transistor in a first connection configuration according to the control signal; a current module, coupled to the first transistor and the second transistor, wherein the current module provides a first current to the first emitter and a second current to the second emitter under the first connection configuration, or the first current module provides the second current to the first emitter and the first current to the second emitter under the second connection configuration according to the control signal; wherein the sensing unit generates a first voltage value by sensing an absolute temperature under the first connection configuration, and generates a second voltage value by sensing the absolute temperature under the second connection configuration; and. 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