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L6712A L6712

erance.

Current Reading: The Rg resistor has to be placed as close as possible to the ISENx and PGNDSx pins

in order to limit the noise injection into the device. The PCB traces connecting these resistors to the read-

ing point must be routed as parallel traces in order to avoid the pick-up of any noise. It's also important to

avoid any offset in the measurement and to get a better precision, to connect the traces as close as pos-

connected to the PHASEx pin. DO NOT CONNECT THE PINS TOGETHER AND THEN TO THE HS

SOURCE! The device won't work properly because of the noise generated by the return of the high side

driver. In this case route two separate nets: connect the PHASEx pin to the HS Source (route together

with HGATEx) with a wide net (30 mils) and the ISENx pin to the LS Drain (route together with PGNDSx).

Moreover, the PGNDSx pin is always connected, through the Rg resistor, to the PGND: DO NOT CON-

NECT DIRECTLY TO THE PGND! In this case the device won't work properly. Route anyway to the LS

mosfet source (together with ISENx net).

Right and wrong connections are reported in Figure 21.

Symmetrical layout is also suggested to avoid any unbalance between the two phases of the converter.

Figure 21. PCB layout connections for sense nets.

To HS Gate

and Source

To LS Drain

and Source

To PHASE

connection

VIA to GND plane

Wrong (left) and correct (right) connections for the current reading sensing nets.

NOT CORRECT

CORRECT