Other Parts Discussed in Thread: TPS2549, TPS2514A
I am using the TPS2544 in a relatively simple application, where I would like to be able to charge a connected device (which may conform to BC1.2 or use a non-standard scheme) at one of 2 current limits - either 2.4A or 1A (selectable by a host controller based on the amount of current available in the system). Obviously I can program these limits using the ILIM_LO and ILIM_HI pins, but I also need to select the correct mode as well setting the ILIM pin accordingly. Presumably I should be using the 'DCP_Auto' mode, but in addition I would like to use a single pin to tell the downstream device whether to pull either 1A or 2.4A (max). The truth table (Table 2) in the datasheet does not seem to list an automatic mode whereby I can achieve this (the closest is setting the CTL pins to 011, but in this case the ILIM_SEL does not seem to have any effect on whether the current limit is set to its high or low setting.
By using a single pin from the host controller (i.e. high/low current available), is there a way to get the TPS2544 to automatically determine the correct charging scheme and then negotiate one of 2 charging current limits?
Thanks!
