Verdin Carrier Board Design Guide
Preliminary
– Subject to Change
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3.4.2.1
Power Block Diagram
Figure 60: Minimalist Power Approach Block Diagram
In this approach, the module is directly powered from a 5V USB power input. It must be noted here
that for being USB compliant, it is required to add a circuit that detects whether the USB power
source is actually able to deliver enough current (USB BC 1.2 or USB PD detection) and the actual
current consumption of the system does not exceed the limits. However, these circuits are not in
this minimalist approach for the sake of simplification. This approach can also be used for any
other power source from 3.135V to 5.5V (e.g. simple barrel connector power supply).
The 5V from the USB is directly connected to the VCC input voltage of the module. No further buck
regulator is needed. The module will start automatically when the VCC is applied. The
VCC_BACKUP is not required for running the module. However, without a coin cell battery on
VCC_BACKUP, the real time clock is only running if the VCC rail is available.
Optionally, a simple push button can be added to the CTRL_PWR_BTN_MICO# and the
CTRL_RESET_MICO# input. Short pressing the power button when the system is booted generates
a software interrupt. Depending on the configuration, the OS will then start shutting down the
5V
Module
RTC
CTRL_RECOVERY_MICO#
RESET_MOCI#
CTRL_PWR_EN_MOCI
WAKE1_MICO#
VCC_BACKUP
VCC
Peripheral
Devices on
Carrier Board
P
o
w
er
M
an
ag
e
m
en
t
/
So
C
5V
(USB)
Input
CTRL_PWR_BTN_MICO#
CTRL_FORCE_OFF_MOCI#
PWR_1V8_MOCI
CTRL_RESET_MICO#
CTRL_SLEEP_MOCI#
(Optional)
(Optional)
