2 Avionics USB Type-C PD Design

Since USB Type-C application designs are trending and becoming more popular, below is an example of a source only USB Type-C power delivery (PD) design in an avionics system. The common output voltages for USB Type-C applications are: 5-V, 9-V, 15-V, and 20-V. The regulated input voltage is sourced from a 24-V aircraft battery that is commonly made from lead acid. When fully charged from the alternator, the input voltage rail can be as high as 28-V. In this application design the block diagram details a system that allows for charging of passenger devices (eg. cellular phone, tablet, laptop) and/or display video from the passenger devices.

Power modules become more impactful in designs that have limited board space or projecst that have limited engineering resources. The TPSM63610 buck power module is selected to meet the following design requirements for USB Type-C applications based on the list of benefits below:

• Small form factor and ease of design in applicaiton
• Dynamic output voltage scalability with simple external feedback control circuitry
• High output current capability with good thermal performance to achieve up to 5 A/100 W design for PD specification

Figure 2-1 Dual-Port USB Type-C Power/Data Source