JAJSJ18A June 2024 – October 2024 LMH1229 , LMH1239
PRODUCTION DATA
The LMH12x9 has a carrier detect circuit to monitor the presence or absence of an input signal. When the input signal amplitude for the selected input exceeds the carrier detect assert threshold, the LMH12x9 operates in normal operation mode.
In the absence of an input signal, the LMH12x9 automatically goes into Power Save mode to conserve power dissipation. When a valid signal is detected, the LMH12x9 automatically exits Power Save mode and returns to the normal operation mode. If the ENABLE pin is pulled low, the LMH12x9 is forced into Power-Down mode. In Power Save mode, both the carrier detect circuit and the serial interface remain active. In Power-Down mode, only the serial interface (SMBus or SPI based on MODE_SEL pin) remains active.
Users can monitor the status of the carrier detect through register programming. This can be done either by configuring the LOCK_N pin to output the CD_N status or by monitoring the carrier detect status register.