Texas Instruments AM335 Series Design Guide

Example Low Power Use Cases www.ti.com
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SPRAC74A–February 2017–Revised March 2017
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AM335x Low Power Design Guide
AM335x GP EVM vs BeagleBone Black DDR Topology
The AM335x GP EVM has been designed to showcase the broad feature set of the AM335x processor,
and has not been optimized for low power consumption. The BeagleBone Black external memory interface
design is better for low-power applications. Table 5 highlights the differences between the two platforms.
Table 5. AM335x GP EVM vs. BeagleBone Black DDR Design
Feature AM335x GP EVM BeagleBone Black Benefit
Density 2 x 512 MB 1 x 512 MB Reducing memory chips and
memory density saves power
Frequency 303 MHz 303 MHz Lower frequency reduces
power consumption at expense
of bandwidth
Technology DDR3 DDR3L
Topology Flyby with VTT Terminationless point-to-point Eliminating VTT significantly
reduces power consumption
Voltage 1.5 1.35 Lower operating voltage
reduces power consumption
4.2 Optimizations Used for Low Power Use Cases
In order to attain these low power states, two device tree configurations were used. The first is called the
am335x-evm-powersave device tree and the second is a modification of this device tree that allows for a
multimedia use case, named am335x-evm-powersave-multimedia. The multimedia use case turns on all
the modules required for an LCD display and audio output. Additionally, ethernet was disabled except for
the network test cases. Table 6 summarizes the configurations used in each test case.
Table 6. Device Tree and Peripherals Use
Test Case Device Tree eth0 SGX
OS Idle am335x-evm-powersave No No
OS Idle with Ethernet am335x-evm-powersave Yes No
IPerf am335x-evm-powersave Yes No
Dhrystone am335x-evm-powersave No No
Multimedia am335x-evm-powersave-
multimedia
No No
Table 7. Peripherals Disabled by Device Tree
Device Tree Devices Marked "Disabled"
am335x-evm-powersave backlight, panel (lcd), lcdc, usb, usb_ctrl_mod, usb0_phy, usb1_phy, usb0, usb1, elm,
epwmss0, gpmc, mcasp1, sham, aes, sgx, pruss
am335x-evm-powersave-multimedia usb, usb_ctrl_mod, usb0_phy, usb1_phy, usb0, usb1, elm, epwmss0, gpmc, sham, aes,
sgx, pruss

Texas Instruments AM335 Series Specifications

General

Brand	Texas Instruments
Model	AM335 Series
Category	Computer Hardware
Language	English