AN4076

Layout recommendations

Doc ID 022923 Rev 1

9/14

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Layout recommendations

In order to maximize the signal by noise ratio it is very important to accurately design the

layout of the printed circuit board (PCB) following some basic principles:

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With reference to Figure 3, and for each of the shunt resistors, directly connect R1 and

R4 terminals to shunt resistor terminals. Furthermore, these two should go close to

each other from resistor to op amp to minimize the introduction of differential electrical

noise.

●

Keep traces between resistors and op amps far away from high voltage traces (even if

on different PCB layers). This would help avoid capacitive couplings.

●

Try to place operational amplifiers and related components as close as possible to

shunt resistors.

●

Follow the suggestions reported in AN2834 about “How to get the best ADC accuracy

in STM32F10xxx devices”.