Texas Instruments EK-TM4C123GXL Data Sheet
LaunchPad Power Interface
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LaunchPad Power Interface
The Tiva C Series LaunchPad has provisions to provide power to a BoosterPack through either the
BoosterPack Interface or the BoosterPack XL Interface. The configuration of power and ground pins on
both of these interfaces must be consistent across LaunchPads from all TI microcontroller families.
BoosterPack Interface or the BoosterPack XL Interface. The configuration of power and ground pins on
both of these interfaces must be consistent across LaunchPads from all TI microcontroller families.
The TM4C123G LaunchPad draws power from either of the on-board USB interfaces as selected by the
power switch in the top left corner of the board. Typically, the USB connection provides 500 mA at 5 V to
the Tiva C Series LaunchPad. The selected USB power source is made directly available to the
BoosterPack XL Interface on the J3.01 pin. This pin is a direct connection with only small decoupling
capacitors provided on the Tiva C Series LaunchPad.
power switch in the top left corner of the board. Typically, the USB connection provides 500 mA at 5 V to
the Tiva C Series LaunchPad. The selected USB power source is made directly available to the
BoosterPack XL Interface on the J3.01 pin. This pin is a direct connection with only small decoupling
capacitors provided on the Tiva C Series LaunchPad.
All LaunchPads, including the TM4C123G LaunchPad, also provide a 3.3-V supply on pin J1.01 of the
BoosterPack Interface. On the Tiva C Series LaunchPad, this supply is sourced by a
BoosterPack Interface. On the Tiva C Series LaunchPad, this supply is sourced by a
which converts the selected 5-V USB power to 3.3 V. The regulator is capable of
sourcing 400 mA at 3.3 V. This 3.3-V supply is shared between the BoosterPack Interface, the in-circuit
debug interface (ICDI), and the target microcontroller. Therefore, under normal circumstances,
approximately 300 mA to 350 mA are available to the BoosterPack Interface. Detailed power management
is the responsibility of the BoosterPack developer who must also manage the application to be run on the
target microcontroller.
debug interface (ICDI), and the target microcontroller. Therefore, under normal circumstances,
approximately 300 mA to 350 mA are available to the BoosterPack Interface. Detailed power management
is the responsibility of the BoosterPack developer who must also manage the application to be run on the
target microcontroller.
The TM4C123G LaunchPad can be powered through an external supply on a BoosterPack. If providing
power to the Tiva C Series LaunchPad from a BoosterPack, move the power select switch to select an
unused USB connection to prevent power bus contention between the BoosterPack and the USB
connection. Power may be supplied to either the 3.3-V or the 5.0-V system, but not both. Providing
external power to both 5 V and 3.3 V would result in a contention between the external power supplies
and the TM4C123G LaunchPad voltage regulator. Providing only 3.3 V results in some lost functionality
(for example, the on-board LEDs may not illuminate). It may also result in reverse current leakage through
the on-board voltage regulator. Therefore, if providing power externally, it is recommended to use either
the existing USB connections or an external 5-V supply from a BoosterPack.
power to the Tiva C Series LaunchPad from a BoosterPack, move the power select switch to select an
unused USB connection to prevent power bus contention between the BoosterPack and the USB
connection. Power may be supplied to either the 3.3-V or the 5.0-V system, but not both. Providing
external power to both 5 V and 3.3 V would result in a contention between the external power supplies
and the TM4C123G LaunchPad voltage regulator. Providing only 3.3 V results in some lost functionality
(for example, the on-board LEDs may not illuminate). It may also result in reverse current leakage through
the on-board voltage regulator. Therefore, if providing power externally, it is recommended to use either
the existing USB connections or an external 5-V supply from a BoosterPack.
Ground connections are available on pins J2.01 and J3.02. These pins provide a ground connection for
both the BoosterPack Interface and the BoosterPack XL Interface, respectively.
both the BoosterPack Interface and the BoosterPack XL Interface, respectively.
Additional power and ground pins are available through labeled pins located in the extreme lower corners
of the Tiva C Series LaunchPad. These pins are connected to the same 3.3 V, 5 V, and ground
connections as the pins on the BoosterPack Interface and the BoosterPack XL Interface.
of the Tiva C Series LaunchPad. These pins are connected to the same 3.3 V, 5 V, and ground
connections as the pins on the BoosterPack Interface and the BoosterPack XL Interface.
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Tiva™ C Series EK-TM4C123GXL LaunchPad: BoosterPack Development
SPMU288A – August 2012 – Revised April 2013
Guide
Copyright © 2012–2013, Texas Instruments Incorporated