The path formed from the input capacitor to the inductor and BOT_SW3 with the low-side current-sense resistor must have short leads and PC trace lengths. The same applies for the trace from the inductor to Schottky diode D1 to the COUT1 capacitor. Connect the negative terminal of the input capacitor and the negative terminal of the sense resistor together with short trace lengths.
The overcurrent-sensing shunt resistor requires noise filtering, and the filter capacitor must be close to the IC pin.
10.1.2 Buck Converter
Connect the drain of TOP_SW1 and TOP_SW2 together with the positive terminal of input capacitor COUT1. The trace length between these terminals must be short.
Connect a local decoupling capacitor between the drain of TOP_SWx and the source of BOT_SWx.
The Kelvin-current sensing for the shunt resistor has traces with minimum spacing, routed in parallel with each other. Place any filtering capacitors for noise near the IC pins.
The resistor divider for sensing the output voltage connects between the positive terminal of itherespective output capacitor and COUTA or COUTB and the IC signal ground. Do not locate these components and their traces near any switching nodes or high-current traces.
10.1.3 Other Considerations
Short PGNDx and AGND to the thermal pad. Use a star-ground configuration if connecting to a non-ground plane system. Use tie-ins for the EXTSUP capacitor, compensation-network ground, and voltage-sense feedback ground networks to this star ground.
Connect a compensation network between the compensation pins and IC signal ground. Connect the oscillator resistor (frequency setting) between the RT pin and IC signal ground. These sensitive circuits must not be located near nodes showing high dv/dt; these include the gate-drive outputs, phase pins, and boost circuits (bootstrap).
Reduce the surface area of the high-current-carrying loops to a minimum by ensuring optimal component placement. Locate the bypass capacitors as close as possible to the respective power and ground pins.