ZHCSHN9A February 2018 – April 2018 LMK05028
PRODUCTION DATA.
Figure 67 shows a reference schematic to help implement the LMK05028 and its peripheral circuitry. Power filtering examples are given for the core supply pins and independent output supply pins. Single-ended LVCMOS, AC-coupled differential, and HCSL clock interfacing examples are shown for the clock input and output pins. An external LVCMOS oscillator drives an AC-coupled voltage divider network as an example to interface the 3.3-V LVCMOS output to meet the input voltage swing specified for the XO or TCXO inputs. The required external capacitors are placed close to the LMK05028 and shown with the recommended values. External pullup and pulldown resistor options at the logic I/O pins set the default input states. The I2C or SPI pins and other logic I/O pins can be connected to a host device (not shown) to program and control the LMK05028 and monitor its status. This example assumes the device will start up from EEPROM mode with an I2C interface (HW_SW_CTRL = 0).