Layout Design

6.2Layout considerations

Place decoupling capacitors C1, C3 and C4 as close as possible to the AC pin, USB pin and BAT pin respectively.

Place the charge current setting resistor as close as possible to the current setting pin to minimize the parasitic capacitance between the current setting pin and ground.

Use wide traces to connect input power source to the AC pin and USB pin, and BAT pin to the battery.

To get better thermal performance, put the EPAD pin of the MC34676B on a large ground plane on the component side, and use a via array to connect the EPAD pin to the ground layer, or the large ground plane on the other layer.

 

Using the Dual 28V Input Voltage Charger with Linear Regulator, Rev. 1.0

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Freescale Semiconductor

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Garmin MC34676B manual Layout considerations