Getting Started, Testing Setup, and Test Results
28
TIDUEW7 – May 2020
Copyright © 2020, Texas Instruments Incorporated
Integrated Power Supply Reference Design for NXP i.MX 6ULL
timx6y login: root
root@timx6y:~#
At the time of writing, the latest software/firmware version for TIDA-050043 is 3.0.1_3, which can be
verified using a simple Linux command.
root@timx6y:~# fw-version
firmware version : 3.0.1_3
There are many other Linux functions and commands that are useful for testing the power supplies and
consumption of TIDA-050043, and the next section provides some examples.
3.1.2.2
Example Linux Commands for Testing TIDA-050043
To figure out which I
2
C devices are on the bus, where "0" means I am looking for I
2
C devices on channel 0
(because the TPS6521815 should be here at 0x24):
root@timx6y:~# i2cdetect -y -r 0
0
1
2
3
4
5
6
7
8
9
a
b
c
d
e
f
00:
--
--
--
--
--
--
--
--
--
--
--
--
--
10: --
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
20: --
--
--
--
UU
--
--
--
--
--
--
--
--
--
--
--
30: --
--
--
--
--
--
--
--
--
--
--
--
--
--
--
--
40: --
--
--
--
--
--
--
--
--
--
--
--
--
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--
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50: --
--
--
--
--
--
--
--
--
--
--
--
--
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60: --
--
--
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--
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--
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70: --
--
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--
--
--
--
--
To verify dynamic voltage scaling is working for the PMIC with respect to the CPU frequency of the
processor, where 792 MHz corresponds to DCDC1 = 1.275 V while 900 MHz corresponds to DCDC1 =
1.325 V:
root@timx6y:~# echo userspace > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
root@timx6y:~# echo 900000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
root@timx6y:~# echo 792000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_setspeed
To run a current sensor application and measure the current on any rail coming out of the TPS6521815
PMIC, where "1" in the first prompt is current sensor IC #1, "1" in the second prompt is channel 1, and
"
curr1_input
" returns a value of 248 mA that is being used by the VDD_ARM and VDD_SOC rails:
root@timx6y:~# test_currentsensor
Enter current sensor no[1-2]: 1
Enter voltage Level[1-3]: 1
/******************************************************************************/
/*
CURRENT SENSOR2
*/
/*
Location of node:/sys/bus/i2c/devices/2-0040/hwmon/h1mon1/
*/
/******************************************************************************/
/* ========================================================================== */
/*
VDD_SOC_IN
*/
/* ========================================================================== */
curr1_crit :
16380 mA
curr1_crit_alarm :
0
curr1_input :
248 mA
curr1_max :
16380 mA
curr1_max_alarm :
0
in1_input :
1104 mV
/******************************************************************************/
Alternatively, software has been written to set up the LCD screen and use it to display the real-time
current monitoring information in addition to displaying the time configured in the real-time clock (RTC)
supplied by the coin cell battery and the always-on power supply.
shows the LCD screen during
power-up, running color configurations tests, and displaying real-time current monitoring with labels and
converted values.
