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
