## Interface Electronics## Lab 01,02,03 LTSPICE and Web report## ***851C |

- Copy of zip files for web report
- LTSPICE
- RC circuit drawing
- Simulations: .OP; .tran; .DC; .AC
- Low pass 3dB frequency
- Create a web report
- Simulate a behavioral ADC, DAC with LTSPICE
- Summary
- ADC DAC setup
- Simulation and analysis of a ramp signal: DNL, INL, LSB
- Simulation and analysis of a sine signal: FFT, DNL, INL, SNR

- Word, Powerpoint
- HTML, JavaScript

- Everywhere, all devices fast access
- No conversion of documents
- Interactive elements

## LTSPICEThe first introduction to use this software and it is quite simple to program. It can build circuits and simulate it in time and frequency domains but it requires to learn more details about simulation commands. The Spice directive function did not not work so it was a troublesome task. ## Web reportThis is the first time to make my own web page by using notepad++. It is useful and everything is prepared for the beginners and any users. but it requires more tags to edit the web page It was the most difficult task to arrange texts with several images in one slide. |

## Sine&pulse simulationDownload ADC DAC simulation setup and test it.This step is very easy and no any troubles. Simulating the sine and pulse inputs though the prepared schematic. The simulation shows input(green) & output(blue) graphs. |

## Fast furier transformLTSPICE can also simulate DFT. The number of data point samples should be set no more than true number of samples. True number of samples = simulation time / maximum time step. |

## LTSPICE INL, DNL FFT AnalysisTest #1 Vin Pulse,setting Step:40.96E-6(655/16) Test #2 Vin Pulse,setting Step:5.12E-6 Javascript can be used to analysis DAC INL,DNL by extracting the raw data instead of LTSPICE The top graph shows the 16 points from the LTSPICE and can compared with ideal one, Here. There is no difference in this first simulation, so values of DNL, INL are zero. If some errors occur like test #2, ADC histogram can analysis INL,DNL. This test is very useful to monitor values of INL,DNL. |

Test #1 Vin sine,setting5.12E-6) Test #2 FFT data processing FFT can be simulated on ADC FFT javascript just by inputing time data integer. It's hard to understand from where the numbers are in the last photo |

## R2R DAC simulationTest # 1sine V(in) simulation by LTSPICE Test # 2 Vin sine,setting5.12E-6 Test # 3 FFT Test # 4 Pulse V(in) simulation by LTSPICE Test # 5 Vin pulse,setting 40.96E-6 In order to analysis some errors R2R DAC is used instead of 4bit DAC here. Real DAC have some errors and the same process like simulation #3,4. Taken long time in this part due to some errors several times. The volume of the raw data was too big and removed .save input of the function in LTSPICE. |

## .measure statementPractice about how to extract data by itself LTSPICEIt's simple to fomulate the function and can measure any values at a specific point. |

Hochschule für angewandte Wissenschaften Kempten, Jörg Vollrath, Bahnhofstraße 61 · 87435 Kempten

Tel. 0831/25 23-0 · Fax 0831/25 23-104 · E-Mail: joerg.vollrath(at)fh-kempten.de

Impressum