3.1 Power Supply
The LMK5B33414 has VDD and VDDO supply pins that operate from 3.3 V ± 5%.
J500 is the main power terminal to the external power supply. Power SMA port VIN1 (J2) provides an alternative
connector style to apply power through coax cable. By default this SMA connector is not populated.
On the EVM, there are three methods for supplying power.
1. The default power configuration uses the onboard DC/DC supply (U500) to power all VDD and VDDO pins
as well as the onboard XO from an external 12-V supply input to VIN4 on J500.
2. The LDO power configuration uses three separate LDO regulators (U9, U10, and U11) to power the VDD,
VDDO, and XO from an external 5-V supply input to VIN1 on J500 (or J2).
3. The direct power configuration allows for separate voltage supplies for the VDD, VDDO, and XO. In the
direct power configuration mode, an external 3.3-V supply is provided to VIN1 to power the VDD pins, an
external 3.3-V supply is provided to VIN2 to power the VDDO pins, and an external 3.3-V supply is provided
to VIN3 to power the onboard XO.
Note
Not every power connection is used or required to operate the EVM. Other power configurations are
possible. See the power schematics in
and
VIN1
VIN2
OUT2_P
VIN1
VIN2
VIN3
VIN4
Input Supply:
12 V to VIN4 on
J500 to power
DCDC
XO Supply:
Select
DCDC1 to
power XO
VDDO Supply:
Select DCDC1
to power VDDO
VDD Supply:
Select DCDC1
to power VDD
GND
Figure 3-2. Default Power Jumper Configuration
shows the default power jumper locations and settings.
configurations for the LMK5B33414.
EVM Configuration
8
LMK5B33414EVM User's Guide
SNAU279 – JULY 2022
Copyright © 2022 Texas Instruments Incorporated
