This subject introduces a kind of nc dc voltage stabilizer， the power supply， by simulation showed circuit， control circuit and digital-to-analog circuit， amplifying circuit four parts， mainly is a set of singlechip intelligent dc power Accurate analog power is to provide power， digital chip， amplifiers， microcontroller is the voltage required by A/D sampling data output voltage， and comparison， if there is A deviation is the limit， adjust output signal output and closure， alarm， The working process of the working status， manostat by SCM outputs drive LED display， Display circuit used to display the size of the output voltage of While the digital technology and the simulation analysis of the concept of technical This topic is a kind of based on singlechip intelligent high-precision dc power supply of simple design， this power can use digital adjustment， the closed-loop real-time monitoring， high precision， and the output of both double overload protection and alarm functions， applicable to all have high accuracy requirements of the It compared with traditional manostat with easy operation， high stability of power and its output voltage size using digital display
Non-electrical signal to the sensor signals into the circuit a total follow-up measurement and analysis， measurement and control system is an indispensable component， it is the nature of various non-electrical signal conversion and signal mutual In the monitoring and control system， the quality and characteristics of the sensor affect the performance of the entire Temperature measurement in the area of negative temperature coefficient (NTC) thermistor in its response has been fast and wide measurement range， the advantages of cheap occupy certain market However， different series of thermistor resistance difference between the thermistor and the same series of individual differences seriously affect the actual use of the Subject to the single-chip microcomputer as the core design of AVR NTC temperature characteristics tester， in the design of high-precision temperature sensor PT100 thermal resistance of the heating environment in which real-time accurate measurement， the use of constant current source circuit as a sensor drive circuit， through the TLC2543 to be the temperature of high-speed data At the same time bridge the use of constant current source of the resistance of the thermistor measured the output signal through the bridge with the PGA-type △ ∑ A / D converter AD7705 is converted to digital From these single-chip temperature， the corresponding value recorded and the data sent through the serial port to the PC， in this way to measure the temperature characteristics of thermistor
Sensors can be transformed into the signal of subsequent signal circuit， measurement and analysis of measurement and control system is an indispensable part of nature， it is each signal and mutual transformation between the In the measurement system， the quality and characteristics of the sensor affects the entire circuit In temperature measurement field， negative temperature coefficient (NTC thermistors) has been the reaction speed， wide measuring range， price cheap holds certain advantages in the But different series resistance of the difference between thermistors and the same series thermistors individual differences of serious impact on the actual use of This topic in AVR singlechip design negative temperature coefficient thermistors temperature characteristics， in the design of test using high temperature sensor for thermistors 16pt100 in real-time accurate measurement of heating environment， use constant-current source circuit， drive circuit as the sensor TLC2543 through high-speed sampling get temperature At the same time constant-current source resistance to thermal resistor of bridge， the output signal measured by bridge with the train ∑ PGA type A/D converter AD7705 converts digital By single-chip microcomputer temperature， resistance to the corresponding data recorded by serial transmitted PC， this approach to measuring temperature characteristics of thermal Keywords: SCM， 16pt100， Constant-current source bridge， Resistance measurements
