 2014 Microchip Technology Inc.

DS00001759B-page 23

UPD1001

3.3.2

PIN CONFIGURATION

The UPD1001 32-SQFN package provides selectable pin configurations via the CFG_SEL0 and CFG_SEL1 pins, as

defined in Table 3-3, "32-SQFN CFG_SELx Configuration Assignments". Table 1-1, "UPD1001 Package/Pin Configura-

tion Summary" provides a summary of the available pin configurations. Refer to Section 2.1, "32-Pin SQFN (32-SQFN)"

for details on the corresponding package pin definitions.

3.3.3

RECEPTACLE TYPE

The USB receptacle type is configurable between Standard-A and Standard-B types via the CFG_SEL0 and CFG_SEL1

pins, as defined in Table 3-3. Each of these receptacle type settings is detailed below.

3.3.3.1

Standard-A (STD-A)

The Standard-A setting informs the device that the designer is utilizing a Standard-A USB PD receptacle.

3.3.3.2

Standard-B (STD-B)

The Standard-B setting informs the device that the designer is utilizing a Standard-B USB PD receptacle.

3.3.4

USB POWER DELIVERY ROLE SELECTION

Depending on the receptacle type selected, the device may support and swap Consumer and Provider roles.

Standard-A receptacle (captive cable or otherwise) AC adapters only support the Provider role, and therefore do not

support role swap. Standard-B receptacle AC adapters are Consumer/Providers that start operation in their default role

of Consumer and support role swapping.

Swapping rules for Standard-B AC adapters are defined as follows:

• When operating as a Consumer:

- Upon starting up, the AC adapter automatically initiates a swap request to its partner to become a Provider. If

the partner rejects the request, the AC adapter will remain in its Consumer role until the partner requests a

swap.

- If the AC adapter receives a swap request from its partner to become a Consumer, it automatically accepts it.

• When operating as a Provider

- The AC adapter will never initiate a swap request to its partner to become a Consumer.

- If the AC adapter receives a swap request from its partner to become a Consumer, it automatically accepts it

and will remain in the Consumer role (until the partner requests another swap back to Provider, or there is a

hard reset or other exception condition that causes the protocol to be re-initiated from startup). The reason for

this behavior is that the partner may have its own other external power which it decided to use instead of the

AC adapter.

Note 1: All AC Adapters will only operate when connected to external AC power. An AC Adapter that is not plugged

to the wall power supply will not be powered from its partner and will therefore not operate at all.

2: Standard-B receptacle AC adapters also support dead battery detection and can perform dead battery

implicit swaps as per the PD specification.

The various Power Delivery Provider and Consumer capabilities are detailed in the following sub-sections.

3.3.4.1

Power Delivery Provider Capabilities

The USB PD Provider capabilities may be selected via the CFG_SEL0 and CFG_SEL1 pins, as defined in Section 3.3,

"Configuration Selection (CFG_SEL0/CFG_SEL1)". Each of the PD Provider capabilities are detailed below. When

capabilities are combined, it is possible that a device can support two or more currents for the same voltage. In this case,

the device will only advertise one voltage with the highest current.

For example, a device that specifies support for “Profile 2 + 5V@3A” must support 5V@2A, 12V@1.5A and 5V@ 3A.

In this case, the device will advertise only two Power Data Objects (PDO): 5V@3A and 12V@1.5A. The device will not

explicitly advertise 5V@2A. However, a consumer that requires 5V@2A will request the 5V@ 3A PDO but only consume

2A.