Table of Contents
Advertisement
power supplies on and off is not required in all designs, for simple designs the power may
be reduced sufficiently by setting all active devices into suspend or power down states.
An OnSemi NCP360 overvoltage protection device is used for two potential benefits:
protection against overvoltage transients (e.g. inductive spike on connection of long
cable) and also inrush current limiting.
3V3X, 1V8 and 0V9 are the always on supplies for xcore.ai and essential support compo-
nents. These use dc-dc supplies from the 5V supply apart from 1V8 which uses a low drop
out linear regulator from the 3V3X supply. This is because 1V8 uses much less current.
The supplies are sequenced such that the 3V3X and 1V8 supplies will be present before
the 0V9 supply is turned on. This meets the requirement of the xcore.ai device that the
VDDIOB18 supply must not be turned on last. For more details of supply requirements
see the XU316-1024-TQ128 datasheet.
The main board 3V3 and 5V supplies are switched such they can be turned off in low
power modes when bus powered. The switched 5V supply is used to generate a dedicated
analog 3V3 supply which is used by the DACs and ADCs as their analog supply. This
supply is separated and generated by a linear regulator to ensure it is low ripple/noise.
The requirement to use less than 2.5mA when in the USB suspend state is a difficult
one to meet. To meet this requirement care must been taken to minimise any unwanted
current draw, steps taken on this board are:
All supplies not required for USB operation are turned off when in suspend.
The xcore.ai VDD supply voltage is reduced to around 0.85V from the nominal 0.9V.
All power management components chosen for low quiescent current.
DC-DC supplies chosen/configured to support high efficiency at low output current
(PFM mode).
Board Net
Figure 22:
X0D22
Power Supply
xCORE GPIO
SUSPEND_N
16 Operating requirements
This development board is, like most exposed electronic equipment, sensitive to Elec-
trostatic Discharge (ESD) events. Users should operate the xcore.ai multichannel audio
board with appropriate ESD precautions in place.
17 Dimensions
The xcore.ai multichannel audio board dimensions are 160x130mm. The mounting holes
are 3.2mm in diameter for use with an M3 screw.
19
xcore.ai Multichannel Audio Board 1v1 Hardware Manual
xCORE GPIO
Port
X0D22
P1G0
X0D41
P8D5
Description
VDD core supply margin. Drive high for 0.85V, high-z
for 0.9V.
Enables the 5V_SW and 3V3 supplies when high.
Advertisement
Table of Contents
