Why do voltages fall in SMT?

Hi all,

As a student in elctronic sciences, I'd like to know why there is a difference in the voltage required for PC boards with surface mounted devices and the voltage needed by traditionnal components like leaded film capacitors?

I wonder if it was the huge use of semi-conductors, in active components to reduce the space on the PC board, that leads to a much lower voltage.

Moreover, one strange aspects is that SMD works under lower voltage but with higher currents: it's hard for me to understand the difference.

Thanks for your advice.

Jeanjean.

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| Hi all, | | As a student in elctronic sciences, I'd like to know why there is a difference in the voltage required for PC boards with surface mounted devices and the voltage needed by traditionnal components like leaded film capacitors? | | I wonder if it was the huge use of semi-conductors, in active components to reduce the space on the PC board, that leads to a much lower voltage. | | Moreover, one strange aspects is that SMD works under lower voltage but with higher currents: it's hard for me to understand the difference. | | Thanks for your advice. | | Jeanjean. | Jeanjean, there is no correlation between SMT and voltage ratings or currents, that�s just determined by the circuit independent from the technology you use to build your product. Due to the smallness of SMT parts their voltage ratings may be somewhat lower than in traditionell outfit but it�s in the responsibility of the engineers to choose the right components for their needs. So for there are more and more components available in SMT you see them more and more used in modern boards. The reasons for this is obviuos, smaller outlines lead to more parts/board and therefor more functions and more current consuming circuitry on a given area.

IMHO Wolfgang

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