Hello.
I found a way to convert HDMI to CVBS with two chips: HDMI->ADV7611->ADV7393->CVBS
Is this the easiest and cheapest solution?
ADV7611
Recommended for New Designs
The ADV7611 is offered in automotive, professional (no HDCP), and industrial versions. The operating temperature range is -40°C to +85°C.
The UG-180 contains...
Datasheet
ADV7611 on Analog.com
Hello.
I found a way to convert HDMI to CVBS with two chips: HDMI->ADV7611->ADV7393->CVBS
Is this the easiest and cheapest solution?
Hi,
Is this the easiest and cheapest solution?
Yes,Please refer i2c configuration in respective design support file page.
ADI does not have a single chip solution for HDMI -> CVBS conversation. But only Chip that can do is ADV8003/ADV8005.
Thanks,
Poornima
Hello.
Can you check schematic, especially:
- data lines connextions for 16-Bit 4:2:2 YCrCb Mode (SDR).
- that both chips I2C connected together and connected to host CPU
- HSYNC, VSYNC, LLC/CLKIN connected correctly
- good or not RESET net, or I should to use SVC (like MAX809)?
Hi,
Please crosscheck your schematic with 4278.ADV7611_EvalNote_RevA.pdf at https://ez.analog.com/video/w/documents/789/adv7611-design-support-files
And also in ADV7393 design support file page link, you can get ADV739x_front_end-SCH_0.pdf under 6428.ADV739x_Evaluation_Board_Documents.zip
Thanks,
Poornima
1) Use 22 or 33 Ohm resistors instead of 75 Ohm series resistors. Normally PCBs are designed for 50 Ohm and you try to match line impedance to the PCB designed impedance. Need 50 Ohm PCBs for HDMI traces
2) Check out https://ez.analog.com/video/f/q-a/11779/pcb-trace-impedance-calculator for a simple tools to specify PCB trace impedances
3) 1V8_PVDD and 1V8_PVDD_DAC need to be very clean rails. I don't see the decoupling caps here. Usually a LC type filter on the rails
4) 7393 DAC output needs a 75 Ohm series resistor with a 75 Ohm load resistor at the end of the cable and the video_out trace designed for 75 Ohm PCB trace.
5) You caught exposed ground pads on both parts. GOOD. You don't know how many people miss that.
Thanks.
I will consider all the comments.
All power rails have filtration like in DS.
About 7393 DAC output. DAC FULL DRIVE OPTION not recomended 75 Ohm series resistor, see picture:
Thanks.
I will consider all the comments.
All power rails have filtration like in DS.
About 7393 DAC output. DAC FULL DRIVE OPTION not recomended 75 Ohm series resistor, see picture:
You are correct. Sorry, I looked at too many schematics that day.