Design & Build 5 Volt Reference Standard

This project is for the hobbyist to design and build a 5 volt precision voltage reference standard that requires no adjustment but still has an accuracy of ±0.01% or better and a temperature coefficient of ±3 ppm/ºC. Also incorporating an auto switch-off and battery monitor feature.


  • 1 x Intersil ISL21009BFB850Z, Precision 5V Voltage Reference ±0.5mV 3ppm/ºC.
  • 1 x SOIC8 to DIL8 IC Adapter PCB SMD Converter Board + Pin Headers (find on eBay).
  • 1 x IRF9630 – ‘P’ Channel MOSFET.
  • 1 x 2N3904 – General NPN transistor.
  • 2 x 5v6 1.3w Zener Diode.
  • 1 x Kingbright 5mm Red/Green LED Tricolour Clear (Manufacturer Part No: L-59EGC).
  • 5 x 1Kohm Resistors (either 1% or 5%).
  • 1 x 10Mohm Resistor (either 1% or 5%).
  • 1 x 10uF 25V Electrolytic Capacitor.
  • 1 x 10uF (16v or 25V) Tantulum Capacitor
  • 1 x 0.1uF Capacitor.
  • 1 x 0.01uF Capacitor.
  • 1 x miniature 6 x 6mm tactile switche with a square button shoulder.
  • 1 x Yellow round button for use with 6 x 6mm tactile switch
  • 1 x Black 4mm Banana Socket
  • 1 x Red 4mm Banana Socket
  • 1 x Project Case, ABS, Aluminium Lid Material, 53mm Length, 83mm Width, 35mm Height, Matrix Board (from Rapid Electronics – Order Code: 30-0650) Cost £1.31.
  • 1 x PP3 Battery Holder with Flying Leads (from Rapid Electronics – Order Code: 18-0163) cost £0.35.

Anyone interested can download the front panel template for this project (in PDF format) from the link below:

Below are the PCB artwork and construction images:

One thought to “Design & Build 5 Volt Reference Standard”

Leave a Reply

Your email address will not be published. Required fields are marked *