SPRUJ10D May 2022 – September 2023
The AM263x LaunchPad is powered through a USB type-C connection. The USB Type-C source should be capable of providing 3A at 5 V and should advertise the current sourcing capability through CC1 and CC2 signals. On AM263x LP, the CC1 and CC2 from USB type-C connector are interfaced to the port controller IC (TUSB320). This device uses the CC pins to determine port attach and detach, cable orientation, role detection, and port control for Type-C current mode. The CC logic detects the Type-C current mode as default, medium, or high depending on the role detected.
The Port pin is pulled down to ground with a resistor to configure it as upward facing port (UFP) mode. VBUS detection is implemented to determine a successful attach in UFP mode. The OUT1 and OUT2 pins are connected to a NOR gate. Active low on both the OUT1 and OUT2 pins advertises high current (3A) in the attached state which enables the VUSB_5V0 power switch to provide the VSYS_5V0 supply which powers other regulators and LDOs.
In UFP mode, the port controller IC constantly presents pull-down resistors on both CC pins. The port controller IC also monitors the CC pins for the voltage level corresponding to the Type-C mode current advertisement by the connected DFP. The port controller IC de-bounces the CC pins and waits for VBUS detection before successfully attaching. As a UFP, the port controller device detects and communicates the advertised current level of the DFP to the system through the OUT1 and OUT2 GPIOs.
The AM263x LP power requirement is 5 V at 3A and if the source is not capable of providing the required power, the output at the NOR gate becomes low that disables the VUSB_5V0 power switch. Therefore, if the power requirement is not met, all power supplies except VCC3V3_TA will remain in the off state. The board gets powered on completely only when the source can provide 5 V at 3A.
OUT1 | OUT2 | Advertisement |
---|---|---|
H | H | Default current in unattached state |
H | L | Default current in attached state |
L | H | Medium current (1.5A) in attached state |
L | L | High current (3.0A) in attached state |
The AM263x LaunchPad includes a power solution based on discrete regulators for each of the power rails. During the initial stage of the power supply, 5 V supplied by the type-C USB connector is used to generate all of the necessary voltages required by the LaunchPad.
Discrete DC-DC buck regulators and LDOs are used to generate the supplies required for the AM263x system on a chip (SoC) and other peripherals.
Component | Function | Voltage In | Voltage Out |
---|---|---|---|
TPS62913 | AM263x Core Digital 1.2 V | 5.0 V | 1.2 V |
TPS74801 | System 3.3 V | 5.0 V | 3.3 V |
TSP74801 | Ethernet PHY 2.5 V | 5.0 V | 2.5 V |
TPS74801 | Ethernet PHY 1.1 V | 5.0 V | 1.1 V |
TPS62177 | Test Automation Header 3.3 V | 5.0V | 3.3 V |