UPD301A

DS00002838B-page 14

 2018-2019 Microchip Technology Inc.

3.3

Configuration Straps

Configuration straps are used during Power-On Reset (POR) or external chip reset (RESET_N) to determine the default

configuration of a particular feature. The state of the signal is latched following deassertion of the reset. Configuration

straps are identified by an underlined symbol name. This section details the various device configuration straps and

associated functions.

3.3.1

PDP_SEL0/PDP_SEL1 CONFIGURATION STRAPS

The PDP_SEL0 and PDP_SEL1 configuration straps are used to define the normative Power Delivery Object (PDO) sup-

port in the Source Role, as defined in Chapter 10 of the USB Power Delivery Specification.

In the Source Role, the Power Delivery Power (PDP) defines all of the normative PDOs returned in the USB PD

Source_Capabilities Message. These correspond to the fixed voltages and currents the Source supports.

The PDP_SEL0 input configuration strap is used to define the PDP value used to configure the UPD301A.

The PDP_SEL1 input configuration strap is used to define the PDP value used to configure the external UPD350 for the

optional UPD301A two port solution.

The PDP_SEL0 and PDP_SEL1 configuration straps are each encoded to one of five possible values determined by

external resistors. Table 3-3 indicates the PDP that each configuration corresponds to and the PDO values that should

be returned in the USB Power Delivery Source capabilities.

3.3.2

I2C_ADDR_SEL CONFIGURATION STRAP

The I2C_ADDR_SEL configuration strap is used to define the default I2C address that the UPD301A will respond to

when operating as a companion MCU. The I2C_ADDR_SEL configuration strap is encoded to one of six possible values

determined by external resistors, as detailed in Table 3-4.

TABLE 3-3:

PDP_SEL RESISTOR ENCODING

PDP_SELx Resistor Value

PDP

PDO 1

PDO 2

PDO 3

PDO 4

200 kΩ Pull-Down

7.5 W

5 V@1.5 A

-

-

-

200 kΩ Pull-Up

15W

5V@3 A

-

-

-

4.7 kΩ Pull-Down

27W

5V@3 A

9 V@3A

-

-

4.7 kΩ Pull-Up

45W

5V@3 A

9 V@3A

15 V@3A

-

10 Ω Pull-Down

60 W

5 V@3 A

9 V@3 A

15 V@3 A

20 V@3 A

TABLE 3-4:

I2C_ADDR_SEL RESISTOR ENCODING

I2C_ADDR_SEL Resistor Value

I2C Slave Address

200 kΩ Pull-Down

1111_000

200 kΩ Pull-Up

1101_000

20 kΩ Pull-Down

1101_001

20 kΩ Pull-Up

1101_010

10 Ω Pull-Down

1101_011

10 Ω Pull-Up

1101_100