Module Sideband and GPIO Control Signals

Sideband signals from the module are used for communicating to, and control of, the expansion board devices.

The PMIC_RESET_N and PMIC_PWRGOOD signals provide module status information to assist debug tasks; it is optional to route these signals on an expansion board or set them as no connect at the module connector if the signals are not used on the expansion board.

The USB signals are necessary to provide connection awareness for various power modes and device state determination.

Signal name

From

To

Connector.Pin

Description

PMIC_PWRBTN_N

Expansion Board

Module

J6.9

Active low output from the expansion board to the module that controls the power state of the module and, by extension, the expansion board, see Power Delivery, Signaling, and Reset for how the PMIC_PWRBTN_N signal controls the module power state based on duration of the low signal.

PMIC_RESET_N

Module

Expansion Board

J6.13

Active low signal output from the module to the expansion board, an expansion board may use this signal to control when the module strapping option signals are driven by the expansion board circuitry. Refer to Power Delivery, Signaling, and Reset for additional details of the PMIC_RESET_N signal.

Leave the PMIC_RESET_N signal floating if not used on the expansion board.

PMIC_PWRGOOD

Module

Expansion Board

J6.33

This power good signal transitions HIGH after the VDD1 and VDD3 supplies are within specification.  Expansion board and mezzanine board designs must ensure that circuitry does not interfere with the state of the compute module boot strap pins. See Boot Strap Signal Isolation for an example isolation circuit.

OTG_EN

Module

USB-C OTG Load Switch

J6.69

Active high, enable 5 V supply for USB OTG

USBC_SEL

Module

Type-C mux

J7.18

Active high or low, Type-C mux port selection signal

VCONN_DCDC_EN

Module

USB-C VCONN Switch

J6.97

Active high, module VCONN input voltage load switch control signal

USB2_ID_PMIC

Expansion Board

Module

J6.20

Active high, indicator for module that a USB OTG cable is connected

Note: Refer to the Compute Module Datasheet Overview for additional electrical specifications.

 

For more complete information about compiler optimizations, see our Optimization Notice.