HMC742A Evaluation Board documentation

Hi mmatusov ,

Good day. I have moved this question about HMC742A to the RF and Microwave community.  Someone here should be able to assist you.

Regards,

Gilbeys

Hi,

Attached are both the schematic and bom files. 

PDFXLS

 Hikieranb ,

Thank you for the files. It appears that the SPDT switch doesn't work as the designer of this board assumed. From the switch datasheet it seems that the pinout is not what one would expect. Even worse, it seems that the actual switch on the board is SPST with the second pair of contacts not doing anything at all, i.e. not matching the datasheet, despite the fact that its marking matches the BOM. As a result of this mess the manual mode of controlling attenuator doesn't work.

/Mikhail

Hi Mikhail,

You can select logic high or logic low with the DIP switch. On the other hand, you can drive the control signals via the pins on J3 connector.

yus said:

You can select logic high or logic low with the DIP switch.

That is how it should work but it doesn't because the switches behave in an unexpected way.