EC49021

USB Charger Enhance IC

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4I01N-Rev.F002

MODE

Function

External pull-high with R1(1K )

Apple 2A mode

External pull-down with R2(1K )

Apple 1A mode

External pull-down with R2(2M )

Apple 2.4A mode

FUNCTION DESCRIPTION

1.

The EC49021 is an USB dedicated charging port (DCP) controller. The built-in auto-detect function can monitors the

voltage of D+ and D- data lines. To provide the correct voltage level on the D+ and D- data lines automatically, the

compliant USB devices can be charged with the charging current as much as possible. That can reduce the charging

time when use the EC49021 as the controller in the USB charge feature kit.

2. MODE truth table

Reference Application Circuit

CAUTION:

When select the charge mode, please make sure the current ability of power source that can provide the

desiredcontinue current. Any maximum continue charging current must not exceed the limited of the maximum current

rating ofthe power source, like wall adapter, vehicle USB charger, and other USB charger.

2.

The EC49021 only control the voltage of D＋/ D － lines on the USB port to support the auto-detect charging

USB devices may affect the charging current. If the remaining battery capacity is low, the charging current may be

high. Conversely the charging current may be low when the remaining battery capacity is high.