I’m looking at the TPS2546 for a dedicated USB charger application. I’m choosing this over some other TI solutions (like TPS2513) because of the port power management feature. Much like the application shown in the datasheet (SLVSBJ2A, Figure 38, page 29), I will have 2 ports on my device. I would like both ports to be set to DCP_Auto mode when the ports are not in use, or being used by a low current device. However, if one port is being used for high current charging (0.9A to 1.5A), the other port must fall down to a lower current mode (using the ILIM_LO setting). Looking at the truth table on page 23, it looks like DCP_Shorted and DCP / Divider 1 are supported with the ILIM_LO current limit (CTL1=1, CTL2=0, CTL3=0, ILIM_SEL=0 and CTL1=1, CTL2=0, CTL3=1, ILIM_SEL=0, respectively). But these modes require choosing “shorted” or “Divider 1” DCP schemes.
Is there a mode that supports lower current (ILIM_LO) but also maintains the automatic capability provided in DCP_Auto mode? Based on my understanding of the ILIM_SEL pin, the settings CTL1=0, CTL2=1, CTL3=1, ILIM_SEL=0 should provide this mode, but that is not what is reported on the truth table on page 23. The goal would be to provide the maximum available charging current and also accommodate a large variety of devices.
