Someone by email asked:
People get lots of help form FMCCOMMx series board and example code. The hardware and software make the SDR related designs very easy.
Recently, I have met some similar requests from several end customers.
Question 1: If add external LNA and let GPIO to control LNA bypass and enable, how to optimize the gain table. I see some setting in the API function. I think the last 2 bits should be set in this case. How about the gain table? Can we give some typical setting for the external LNA(bypass function). This is very common in customer design, as they more likely to add external LNA and SAW filter before AD936X.
/* External LNA Control */
uint32_t elna_settling_delay_ns; /* adi,elna-settling-delay-ns */
uint32_t elna_gain_mdB; /* adi,elna-gain-mdB */
uint32_t elna_bypass_loss_mdB; /* adi,elna-bypass-loss-mdB */
uint8_t elna_rx1_gpo0_control_enable; /* adi,elna-rx1-gpo0-control-enable */
uint8_t elna_rx2_gpo1_control_enable; /* adi,elna-rx2-gpo1-control-enable */
Question 2: In some customer design, ADV7513 give more small size compare with ADV7511. In this case, customer can’t make the project working well. Can you give me some guidelines how to modify the NO-OS project to make the ADV7513 to work.
Thanks for your help!