MP28164 – SINGLE-INDUCTOR, BUCK-BOOST CONVERTER WITH 4.2A SWITCHES

MP28164 Rev. 1.0

www.MonolithicPower.com

18

3/28/2016

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PCB Layout Guidelines

Efficient PCB layout of the high-frequency

switching power supplies is critical for stable

operation. Poor layout can result in reduced

performance, excessive EMI, resistive loss, and

system instability. For best results, refer to Figure

3 and follow the guidelines below.

1. Place the input capacitor and output capacitor

close to VIN, VOUT, and PGND.

2. Place the VCC decoupling capacitor close to

VCC and AGND.

3. Keep the FB resistor divider very close to FB.

4. Keep the FB trace far away from noise

sources, such as SW1 and SW2.

5. Ensure the layout of the copper of GND, VIN,

and VOUT is wide enough to conduct high

current and lower the die temperature.

6. Place vias in the GND copper around the chip

for better thermal performance.

Top Layer

GND

Bottom Layer

Figure 3: PCB Layout Recommendation

Figure 4: Reference Circuit for PCB Guide

Design Example

Table 1 is a design example following the

application guidelines for the specifications

below:

Table 1: Design Example

1.8 - 5.5

1.2 - 5.5

3.3V

The detailed application schematic is shown in

Figure 5, and the performance can be found in

the

Typical

Performance

Characteristics

sections.