i.MX 6ULL
TPS6521815
INA3221
INA3221
VIN+1
VIN-1
VIN+2
VIN-2
VIN+3
VIN-3
SDA
SCL
A0
VIN+1
VIN-1
VIN+2
VIN-2
VIN+3
VIN-3
SDA
SCL
A0
VS
GND
GND
VS
VPU
VP
U
VDD_3V3
VDD_3V3
VDD_3V3
10K
DCDC1
DCDC2
DCDC3
DCDC4
LS1
LS2 & 3
VDD_SOC_ARM_IN
NVCC_DRAM
VDD_HIGH_IN_3V3
VDD_1V8
VDD_3V3
USB_OTG_VBUS
I2C2_SDA
I2C2_SCL
I2C2_SDA
I2C2_SCL
System Overview
14
TIDUEW7 – May 2020
Copyright © 2020, Texas Instruments Incorporated
Integrated Power Supply Reference Design for NXP i.MX 6ULL
2.3.3
INA3221 - Current Monitor
To measure the live current information, a current sense circuit is inserted in series with the power nets
from the PMIC to the processor. The current sensing is done with the INA3221 device. There are two
devices used to monitor all the TPS6521815 PMIC power rails. The wiring is shown in
. The
address pin A0 of the INA3221 device needs to be terminated according to
Figure 13. INA3221 Current Sensor Wiring From PMIC to Processor
(1)
Both of the I
2
C lines, SDA and SCL, require a pull-up resistor. A resistance of 2.2-k
Ω
is used to pull-up these
open-drain signals to 3.3V
Table 3. INA3221 I
2
C Slave Address Options
7-BIT BINARY ADDRESS
7-BIT HEX ADDRESS
ADDR PIN TERMINATION
1000000b
0x40
GND
1000001b
0x41
V
S
1000010b
0x42
SDA
1000011b
0x43
SCL