 2014 Microchip Technology Inc.

DS00001760B-page 23

UPD1002

3.0

FUNCTIONAL DESCRIPTIONS

This chapter provides functional descriptions for the various device sub-systems:

• Resets

• Power Management

• Configuration Selection (CFG_SEL0/CFG_SEL1)

• Voltage/Current Monitors (VMON/IMON)

• SPI ROM Controller

3.1

Resets

The device includes the following reset controls:

• Power-On Reset (POR)

• External Chip Reset (RESET_N)

A system reset event via the external RESET_N pin or POR causes the following:

• All registers are set to their default values

• Pins are placed into their default state

The rising and falling Power-On Reset thresholds for each power supply are detailed in Table 3-1.

After power up, the POR initially de-asserts after the Rising Threshold is passed. In the event that the supply drops

below the Falling Threshold, the POR will assert. The POR stays asserted until the Rising Threshold is once again

crossed.

3.2

Power Management

The device will enter low power modes based on the state of the connection to the power delivery port partner. The low

power connection states are defined for the device operating as a Provider (Provider/Consumer) or a Consumer (Con-

sumer/Provider).

The device provides the following power states:

• Provider: Wait Insert State

• Consumer: Sink Discovery State

3.2.1

PROVIDER (OR PROVIDER/CONSUMER) POWER STATE

The device Provider configuration will enter a low power mode when it is not connected to a port partner and when a

Standard-A plug is not inserted in the receptacle.

3.2.1.1

Wait Insert State

In the Wait Insert State, the device utilizes the insertion detect feature to enter a standby mode when waiting for a Stan-

dard-A plug to be inserted in the receptacle. On insertion of a Standard-A plug, the device will exit from the standby

mode, initiate operation by enabling the supply output to 5Vsafe, and initiate the discovery of a port partner.

3.2.2

CONSUMER (OR CONSUMER/PROVIDER) POWER STATE

The device Consumer configuration enters a standby mode when it is not connected to a provider.

3.2.2.1

Sink Discovery State

In the Sink Discovery State, the device waits for the presence of VBUS to indicate a connection to provider. The device

enters a standby state when waiting for the presence of VBUS. At the presence of VBUS, the Consumer exits the

standby state and resumes full operation to establish a negotiated power contract with the Provider.

TABLE 3-1:

POR THRESHOLDS

POR

Rising Threshold

Falling Threshold

VDDIO Supply

2.7 V

2.35 V

VTR Supply

2.85 V

2.7 V