LMH1228: Interface forum

Terry Zhang

Part Number: LMH1228

Hello, I encountered a problem when using LMH1228:

I try to use LMH1228 Reclock，but i never turn it on，it be used Bypass mode；

I try to setup 0x1C ，but it always seems to be Unlock mode, but it always seems Bypass mode。

I try to set the OUT_CTRL，H F or R L ，it without any distinction，no change at output ；

How can i make the LMH1228 worked at reclock mode?

0 Nasser Mohammadi over 2 years ago

Hi Terry,

After powering up the device:

1). Please check to make sure OUT_CTRL pin is either high or float - note table 6 of the data sheet.

2). Data rate/pattern should be SMPTE data rate and pattern(or similar)..

3). Lock pin is open collector and there should be a pull up Resistor 2k-5K ohm on this pin.

4). You can use GUI for the LMH1228 device. In default mode, it sets up the device to lock at the SMPTE data rates.

Regards,Nasser