Power Supply
8
SPNU509C – September 2011 – Revised November 2018
Copyright © 2011–2018, Texas Instruments Incorporated
Introduction
1.8
Power Supply
The HDK board operates from a 12 V external power supply connected to the main power input
(P1), a 2.5 mm, barrel-type plug. Internally, the +12 V input is converted into +1.2 V, +3.3 V and +5.0 V
using Texas Instruments swift voltage regulators and PTH power module. The +1.2 V supply is used for
the MCU core while the +3.3 V supply is used for the MCU's I/O buffers and other module on the board.
The +5.0 V supply is used for ADC power (second option) and USB VBUS.
There are multiple power test points on the HDK board. The three main test point pairs provide a
convenient mechanism to check the HDK’s current for each supply.
shows the voltages for each
test point and what the supply is used for.
Table 1-2. Power Test Points
Test Point Pair
Voltage
Voltage Use
TP14 and TP15
1.2 V
MCU core
TP16 and TP17
3.3 V
MCU IO and logic
TP18 and TP19
1.2 V
MCU PLL
TP20 and TP21
3.3 V
MCU Flash pump
TP22 and TP23
3.3 V or 5.0 V
(J8 to enable 5 V)
MCU MibADC, and ADREFHI
