Version 1.0
Page 18
Figure 8
– I2C I/O Expander Addressing
2.7 I2C Switch/Multiplexer
The UltraZed-EG SOM uses a
Texas Instruments
TCA9543APWR
(14-pin TSSOP)
Serial Bus
Switch/MUX with Interrupt. The Zynq Ult MPSoC controller required for I2C is named I2C1 and it
exists at MIO [25:24].
Table 13
– I2C1 TRM Pin Mapping
IO NAME
TRM SIGNAL NAME
NET NAME
PS_MIO24
SCL_OUT
MIO24_I2C1_SCL
PS_MIO25
SDA_OUT
MIO25_I2C1_SDA
The I2C Switch/MUX allows for selection of control of the end-user carrier card two-wire serial interface or
alternatively one could select the PMBUS interface that is tied to the UltraZed-EG SOM main multi-output
power supplies as well as any device that may exist on the end-user carrier card PMBUS through the JX2
connector. The two-wire serial interface on the Zynq Ult MPSoC is used as the serial source for to
the TCA9543A.The following table shows the connections to the
TCA9543A
device.
Table 14
– Texas Instruments TCA9543A Pin Mapping
SWITCH/MUX
NAME
SWITCH/MUX
PIN
FUNCTION
NET NAME
A0
1
ADDRESS
GND
A1
2
ADDRESS
GND
RESET_N
3
RESET
P6_I2CMUX_RST_N
INT0_N
4
INTERRUPT0
CC_INT_N
SD0
5
SERIAL DATA0
CC_SDA
SC0
6
SERIAL CLOCK0
CC_SCL
GND
7
GROUND
GND
INT1_N
8
INTERRUPT1
N/C
SD1
9
SERIAL DATA1
PMBUS_SDA
SC1
10
SERIAL CLOCK1
PMBUS_SCL
INT_N
11
INTERRUPT
P4_I2CMUX_INT_N
SCL
12
SERIAL CLOCK
MIO24_I2C1_SCL
SDA
13
SERIAL DATA
MIO25_I2C1_SDA
VCC
14
POWER
+2.5V
The following table should provide a clearer understanding of how the TCA9543A is expected to function in
the system.