A fid micro-current amplifier capable of automatic calibration and its calibration method
An automatic calibration and micro-current technology, which is applied in the field of gas chromatograph FID detection, can solve the problems of uncorrectable component errors and uncertainties, and achieve the effect of improving repeatability and accuracy and improving adaptability
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
Method used
Image
Examples
Embodiment 1
[0032] This embodiment provides a FID micro-current amplifier capable of automatic calibration. The signal input end of the FID micro-current amplifier is connected to a micro-current source. The micro-current source includes a reference voltage generation circuit, a program-controlled line variable voltage output circuit, a filter circuit and line variable voltage-current conversion circuit.
[0033] The reference voltage generation circuit includes a voltage reference source VR1, a first resistor R1, and a first capacitor C1, and the output voltage of the voltage reference source VR1 is filtered by the first resistor R1 and the first capacitor C1 before entering digital-to-analog conversion The reference voltage input terminal of chip U1.
[0034] The program-controlled line variable voltage output circuit includes a digital-to-analog conversion chip U1 (DAC chip), a high-voltage operational amplifier U2A and a digital control part, and the digital-to-analog conversion chip ...
Embodiment 2
[0048] The present invention provides a method for calibrating the FID microcurrent amplifier described in Embodiment 1, and its flow process is as follows:
[0049] 1) Set the control terminal of the switch Q1 to a high level, so that the switch Q1 is turned on; test and record the basic input current, and the input current at this time is the reference leakage current of the system;
[0050] 2) The control terminal of the switch Q1 is set to a low level, and the digital control part outputs a line variable voltage with a fixed slope according to the required set current and the value of the output capacitor C2 to obtain a continuous output current;
[0051] 3) Through the analog-to-digital conversion part of the chromatograph host, read and record the final output voltage of the output terminal of the micro-current amplifier; three points of 1pA, 10pA, and 100pA are used as test points, and each point is repeatedly measured 2-3 times, and other data Read after stabilization ...
PUM
Login to View More Abstract
Description
Claims
Application Information
Login to View More 


