DRV8412_15 Datasheet, PDF (27/42 Pages) Texas Instruments – DRV84x2 Dual Full-Bridge PWM Motor Driver

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10 Layout
DRV8412, DRV8432
SLES242G – DECEMBER 2009 – REVISED DECEMBER 2014
10.1 Layout Guidelines
10.1.1 PCB Material Recommendation
FR-4 Glass Epoxy material with 2 oz. copper on both top and bottom layer is recommended for improved thermal
performance (better heat sinking) and less noise susceptibility (lower PCB trace inductance).
10.1.2 Ground Plane
Because of the power level of these devices, it is recommended to use a big unbroken single ground plane for
the whole system / board. The ground plane can be easily made at bottom PCB layer. In order to minimize the
impedance and inductance of ground traces, the traces from ground pins should keep as short and wide as
possible before connected to bottom ground plane through vias. Multiple vias are suggested to reduce the
impedance of vias. Try to clear the space around the device as much as possible especially at bottom PCB side
to improve the heat spreading.
10.1.3 Decoupling Capacitor
High frequency decoupling capacitors (100 nF) on PVDD_X pins should be placed close to these pins and with a
short ground return path to minimize the inductance on the PCB trace.
10.1.4 AGND
AGND is a localized internal ground for logic signals. A 1-Ω resistor is recommended to be connected between
GND and AGND to isolate the noise from board ground to AGND. There are other two components are
connected to this local ground: 0.1-µF capacitor between VREG to AGND and Roc_adj resistor between
OC_ADJ and AGND. Capacitor for VREG should be placed close to VREG and AGND pin and connected
without vias.
10.2 Layout Example
10.2.1 Current Shunt Resistor
If current shunt resistor is connected between GND_X to GND or PVDD_X to PVDD, make sure there is only one
single path to connect each GND_X or PVDD_X pin to shunt resistor, and the path is short and symmetrical on
each sense path to minimize the measurement error due to additional resistance on the trace.
An example of the schematic and PCB layout of DRV8412 are shown in Figure 20, Figure 21, and Figure 22.
Copyright © 2009–2014, Texas Instruments Incorporated
Product Folder Links: DRV8412 DRV8432
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