What is it?

Its basically an op-amp circuit that can be powered by Battery's or an Bench power supply. With the potentiometer on the left hand side it is possible to limit the available Range for the voltage output. The potentiometer on the right hand side are for the two output channel to control their output voltages.

Depending on the op-amp are some limitations with the available voltage and the maximum output current. It is possible to use any quad op-amp with standard pin-out in a dip package.

A build in adapter allow to stick in your multimeter probes and connect then to 2.54mm header so it is easy to connect with jumper wire to other header or your breadboard.

Each output has a current jumper (CJx) for current measurement with a multimeter. The sense pin eliminates the burden voltage drop over your multimeter. With this feature it is possible to change current ranges on your multimeter without an effect on the voltage output. To improve the handling with the multimeter probe and to avoid painful contact to the exposed pin on the PCB backside the PCB is mounted on case that gives the Voltage Ranger a professional look and feel.

Why did you make it?

On my bench I had one Bench power supply that is pretty useless in the low ranges of voltage and current. So I thought of an possibility to connect the supply on battery's and vary the voltage. The final design is inspired by the μCurrent from David L. Jones (EEVBlog).

What makes it special?

• Examples available on Github (click Sourche Code on the right hand side)
• Measurements with multimeter on small voltages and currents
• DC-Signal simulation with limits
• Powering low power circuits
• Connect your Multimeter to Pin header with the test-points
• Burden voltage free current measurement points
• Configuration for different modes with jumper wire
• PCB with matching case
• Comes assembled (But flipped you need an PH1 screwdriver!)
• To protect the pins on transportation the PCB is shipped flipped so you need an PH1 screwdriver