User's Manual l MBa8x UM 0100 l © 2021, TQ-Systems GmbH
Page 22
Figure 8: Placement
3.10
I
2
C devices
Two primary I2C buses are available. I2C1 connects all I2C devices on the module and the MBa8x. The voltage level of both I2C
buses is 1.8 V. In order to be able to connect I2C devices with 3.3 V voltage level, there are level converters on the module and
the mainboard. However, 3.3 V signals of the module are not available on the mainboard and vice versa.
Various video
connectors
TQMa8x
SE97BTP
Pin header
PF8100 #1
24LC64T
Level
translator
PCF85063
1,8 V Level
I2C1
I2C2
PMIC_I2C
PF8100 #2
TLV320
(Audio)
mikroBUS
Mini-PCIe
PCIe (M.2)
Level
translator
PCIe-Clock
MIPI_CSI[1:0]_I2C
Temperature
1,8 V Level
PMIC_I2C
I2C2_1V8
I2C1_1V8
I2C1_3V3
HDMI_RX_DDC
MIPI_CSI[1:0]
HDMI_RX_DDC
SE050
MIPI_DSI[1:0]_I2C
MIPI_DSI[1:0]
HDMI_TX_DDC
LVDS [1:0]_CMD
LVDS[1:0]_I2C
2k
Figure 9:
Block diagram I
2
C bus
Further I2C devices are in use on the TQMa8x, which is why the already occupied I2C addresses must be taken into account.
Depending on the application and software load, the data throughput may be limited due to the number of I2C devices used.
The following placement options are available on the MBa8x: For I2C1, unpopulated pull-ups are provided since 2.2 kΩ pull-ups
are already populated on the TQMa8x. For I2C2 4.7 kΩ pull-up resistors to 1.8 V are provided, as these are not populated on the
module.
Both I2C buses are connected to the pin headers. The following table shows the used addresses of the respective buses: