UPD301A

DS00002838B-page 8

 2018-2019 Microchip Technology Inc.

2.2.2

TWO-PORT APPLICATIONS (E.G., AUTOMOTIVE REAR SEAT CHARGING)

Some applications, such as a automotive rear seat charging port, may need up to two USB Type-C™ power delivery

ports. These ports can be implemented by connecting a UPD301A and a UPD350 via the SPI interface, as shown in

Figure 2-2. The UPD301A will execute the stack for the UPD350. The two-port implementation supports dynamic power

allocation (e.g., go-to power min based on an external input). The integrated DAC from the UPD301A and additional

GPIOs from the UPD350 control the DC-DC converter, selecting the voltages, and control the load switch to regulate

and protect the output voltage. The load switch can also be replaced by discrete FETs and over-current / over-voltage

protection circuits.

FIGURE 2-2:

SYSTEM BLOCK DIAGRAM - TWO-PORT APPLICATION

Microchip

UPD301A

CC1

CC2

VBUS

60W Load 

Switch

DC In

Load Switch

DC‐DC 

Converter

VBUS

60W Load 

Switch

DC In

Load Switch

DC‐DC 

Converter

Microchip

UPD350

CC1

CC2

SPI

M

S

DC In

Configuration 

Straps

BOO T_SEL

DC_DC_SEL

PDP_SEL0

PDP_SEL1

I2C_ADDR_SEL