SLLSES1D December 2015 – September 2020 HD3SS3220
PRODUCTION DATA
The HD3SS3220 can be configured as a DFP only by pulling the PORT pin high through a resistance to VDD5. The HD3SS3220 device can also be configured as a DFP-only device by changing the MODE_SELECT register default setting with PORT pin left floating. In DFP mode, the HD3SS3220 constantly presents R(p) on both CC lines. In this mode, the HD3SS3220 will initially advertise default USB Type-C current. The Type-C current can be adjusted through CURRENT_MODE pin or I2C if the system wishes to increase the current advertisement. The HD3SS3220 will adjust the R(p) resistors to match the desired advertisement.
A DFP monitors the voltage level on the CC pins looking for the R(d) termination of a UFP. When a UFP is detected and HD3SS3220 is in the attached. SRC state, the HD3SS3220 pulls the ID pin low to indicate to the system the port is attached to a device (UFP). Additionally, when a UFP is detected, the HD3SS3220 supplies VCONN on the unconnected CC pin if R(a) is also detected.
The following list describes the steps for enabling DFP through I2C:
When configured as a DFP, the HD3SS3220 can operate with older USB Type-C 1.0 devices except for a USB Type-C 1.0 DRP device. The HD3SS3220 cannot operate with a USB Type-C 1.0 DRP device. This limitation is a result of a backwards compatibility problem between USB Type-C 1.1 DFP and a USB Type-C 1.0 DRP.