The device provides innovative Input Current Optimizer (ICO) to identify maximum power point without overloading the input source. The algorithm automatically identifies maximum input current limit of power source without entering VINDPM to avoid input source overload.

This feature is enabled by default (EN_ICO=1) and can be disabled by setting EN_ICO bit to 0. The algorithm runs automatically when EN_ICO bit is set. The algorithm can also be forced to execute by setting FORCE_ICO bit regardless of input source type detected (EN_ICO = 1 is required for FORCE_ICO to work).

The actual input current limit used by the Dynamic Power Management is reported in ICO_IINDPM register while Input Current Optimizer is enabled (EN_ICO = 1) or set by IINDPM register when the algorithm is disabled (EN_ICO = 0). In addition, the current limit is clamped by ILIM pin unless EN_EXTILIM bit is 0 to disable ILIM pin function .

When the algorithm is enabled, it runs continuously to adjust the input current limit of Dynamic Power Management (IINDPM) using ICO_IINDPM register until ICO_STAT[1:0] and ICO_FLAG bits are set (the ICO_FLAG bit indicates any change in ICO_STAT[1:0] bits). The algorithm operates depending on battery voltage:

1. When the battery voltage is below VSYSMIN, the algorithm starts ICO_IINDPM register with IINDPM which is the maximum input current limit allowed by system.
2. When the battery voltage is above VSYSMIN, the algorithm starts ICO_IINDPM register with 500 mA which is the minimum input current limit to minimize adapter overload.

When the optimal input current is identified, the ICO_STAT[1:0] and ICO_FLAG bits are set to indicate the input current limit in ICO_IINDPM register will not be changed until the algorithm is forced to run by the following events (these events also reset the ICO_STAT[1:0] bits to '01'):

1. A new input source is plugged-in, or EN_HIZ bit is toggled
2. IINDPM register is changed
3. VINDPM register is changed
4. FORCE_ICO bit is set to 1
5. VBUS_OVP event

If the optimal current is not identified (for example if output power < maximum input power), the ICO routine is suspended until more power is needed from the input. In this case, the ICO_STAT bits are set to '11'.