- on Power Supplies
- Published in issue 7/2011 on page 76
Floating Supply for Panel Meters
Digital voltmeter modules usually exist in two versions: the ‘really cheap’ which require isolation between their supply voltage and the voltage being measured. The ‘more expensive’ (expect double!) which accept a common ground. Considering the low power consumption of these modules (around 1 mA), it is simple and worthwhile to design a little circuit that will allow isolation for this type of equipment.