DocID025240 Rev 2

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AN4355

Layout suggestions

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Layout suggestions

The L648x devices require external MOSFETs for implementing the power stage which

drives the motor phases. The electrical connections between the device and the external

MOSFETs are critical and particular attention must be paid to reduce parasitic inductances.

Figure 16 shows the critical paths which should be designed to be as short as possible and

the area of the circuits should be minimized avoiding the sensitivity of such structures to the

surrounding noise. Typically, a good power system layout keeps the power MOSFETs as

close as possible to the related gate driver.

Figure 16. Layout critical paths