The LMKDB1204 can be configured to start up in one
of two modes during power-on/reset (POR). SMB_EN pin determines the mode of operation during
power supply ramp up. Below are both of the modes for the device:
- SMBus Mode Disabled (EVM default): When
SMB_EN pin is set to low during the power up, SMBus
mode is disabled, output enable (OE) pin control is
possible on all outputs, and CLKIN_SEL_tri pin is
enabled to select which CLKIN drives which output
bank.
- SMBus Mode Enabled: When SMB_EN pin is set
to high during power up, SMBus mode is enabled and OE3# and CLKIN_SEL can only be
controlled via SMBus.