================= /*
- Files: LM399 Reference board published on www.circuitvalley.com
- Author: Gaurav singh
- email : gauravsingh@circuitvalley.com
- copy right : www.circuitvalley.com
- https://www.circuitvalley.com/2018/08/diy-open-source-lm399-voltage-reference-10v-dmm-calibrate.html
- https://www.circuitvalley.com/2018/11/diy-open-source-lm399-V2-voltage-reference-10v-dmm-calibrate.html */