Intrinsyc LANTRONIX Open-Q 820 User Manual page 34

3.9.9 Education / GPIO header J54 (EXP2)
Education/ GPIO header expansion J54 is a 20 pin connector that provides access to BLSP1 signals with level
shifters. It is ideally used for connecting external peripherals such as microcontrollers and any other devices
that are based on I2C, SPI, UART, UIM and GPIO. Please refer to the µSOM carrier board schematic for the
level shifter, target voltage and current rating depending on stuffing option. The education expander also
supports multiple voltage ratings. The table below outlines the configurations for these settings:
Voltage Rails
MB_VREG_3P3 – 3.3 V
VREG_S4A_1P8 – 1.8V
MB_VREG_5P0 – 5.0 V
The following are the detailed pin out information for education header J54.
Table 3.8-4 Education Connector Expansion Header J54 Pin Out
Description
NC
BLSP1_3_3P3(3.3V)
Open-Q™ 820 / 820Pro µSOM Dev Kit User Guide
Figure 12 J54 Education / GPIO header
Signal Pin NO
NC J54[1]
BLSP1_SPI_ J54[3]
MOSI (APQ-
GPIO0)
Open-Q 820 µSOM Development Kit
Resistors to Populate (0 Ohm)
R150 (Default)
R149
R151
Description
VREG_S4A 1.8V
voltage regulator max
150mA
VDD_EXP2 (Default
3.3V Power Supply)
max 300mA
Signal Pin NO
VREG_S4A_1P8 J54[2]
VDD_EXP2 J54[4]
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