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where should i put the ground on a portable circuit/ battery powered circuit? Answered

this and vcc are the two things at the moment i don't know how to link up.


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Best Answer 9 years ago

Ground is what you make it... Just look at the left side of the picture I attached. Anywhere in the circuit that was supposed to be ground I made to be 4.5V with that a voltage divider. That way the negative terminal of the battery is actually seen as -4.5V by the circuitry.

As a note: You should mess around with the values of those resistors. Low values give you a good supply of current to your circuit, but at the cost of being less efficient. High values give you lower current, but this make it use less of the battery. Design accordingly.

LED triangle wave.jpg

9 years ago

In a portable circuit "ground" is simply the return for circuit currents, shared by all subcircuitry as a common point of return. To reduce circuit noise, a star ground is often used, in which all secondary circuit "grounds" are connected to one point on the virtual ground plane, which in turn is often provided by defining a region of the printed circuit board for this purpose. a bus bar or a short length of large gauge wire can serve the purpose as well.

Vcc is the power supply positive voltage. In a simple dc circuit (ex: +12V, COM), the "ground" would be defined by the negative terminal (COM or - ).

In a split supply (ex: +12V, -12V, and com), the "ground is usually defined as the "COM" connection. Vcc is again +12V, and a new entry, Vee, is often used to define the negative voltage.

In a psuedo split supply (+12V, com) where a secondary virtual ground is defined by secondary circuitry to provide a ~+6V, -6V, com1(6V to COM), com1 would be considered to act as the virtual ground.