EVM Configuration
11
SNAU236A – June 2018 – Revised December 2018
Copyright © 2018, Texas Instruments Incorporated
LMK05318EVM User's Guide
NOTE:
To ensure proper start-up into SPI Mode, the HW_SW_CTRL, STATUS0, and
STATUS1/FDEC pins must all be floating or biased to V
IM
(0.8-V typical) before the PDN pin
is pulled high. These three pins momentarily operate as 3-level inputs and get sampled at
the low-to-high transition of PDN to determine the device start-up mode during POR. If any of
these pins are connected to a host device (MCU or FPGA), TI recommends using external
biasing resistors on each pin (10-k
Ω
pullup to 3.3 V with 3.3-k
Ω
pulldown to GND) to set the
inputs to VIM during POR. After power-up, the STATUS pins can operate as LVCMOS
outputs and overdrive the external resistor bias for normal status operation.
3
EVM Configuration
The LMK05318 is a highly configurable clock chip with multiple power domains, PLL domains, and clock
input and output domains. To support a wide range of LMK05318 use cases, the EVM was designed with
more flexibility and functionality than needed to implement the chip in a customer system application.
This section describes the power, logic, and clock input and output interfaces on the EVM, as well as how
to connect, set up, and operate the EVM.
An overview of some key components are shown in
,
, and
Table 5. Key EVM Components
ITEM NO.
REF DES
DESCRIPTION
1
U5
LMK05318 DUT
2
A
VIN1 (terminal)
or
External Supply Input (+5 V using default configuration)
B
J2 (SMA)
3
A
Y1
or
Y1: 48.0048-MHz XO (Default). Located on bottom side.
B
J4/J5
or
J4/J5: SMA Ports for External XO_P/N input clock.
Requires minor rework before first use (see
C
U10
U10: LMK61E2 Programmable OSC.
Requires minor rework before first use (see
4
J6/J7 and J8/J9
SMA Ports for DUT Clock Inputs (PRIREF_P/N and SECREF_P/N)
5
J12/J13, J14/J15,
J18/J19, J20/J21,
J24/25, J26/J27,
J30/J31, J32/J33
SMA Ports for DUT Clock Outputs (OUT0_P/N to OUT7_P/N)
6
S4
Toggle Switch for DUT Power-Down/Reset (PDN pin)
7
JP18
Jumper for DUT Clock Input Selection (REFSEL)
8
D7, D8
Status LEDs for DUT STATUS[0:1] pins
9
JP20
Jumpers Header for I
2
C/SPI interface (MCU to DUT)
10
J35
USB Port for MCU