DS90CF384A: PCB Guidelines

Hi Arun,

1. Does RGB output requires RX out resistor? if yes kindly share the resistor value?
   
   1. Yes. The resistors are needed on the receiver side; therefore, you do not need to place here.
2. Does RGB output essentially requires Length matching?
   1. Yes. OLDI/RGB is requires length match.
3. Does RGB output requires 50-ohm impedance trace?
   1. Yes
4. Please share the PCB design files for routing reference
   1. This device is a long time released device. I need sometime to look into this if there is any EVM design file.

Aaron

We are using DS90CF384AQ-Q1 receiver,kindly suggest termination resistor value for RGB data line.  Is there a preferred placement of termination resistor?.

Please find the attached schematics and review the same

Dear Aaron,

Please verify the pin mapping in the above-attached schematics. We are using the IC DS90CF384AQ for converting LVDS signals from the processor to RGB signals to LCD. We have followed the pin mapping from the document  SNLA014A (Table 1). confirm the pin mapping is correct for the mentioned application.

Kindly share the design files.

Hi Arun,

• Is there a preferred placement of termination resistor?
  • The termination resistor should be at the receiver side (LCD panel) not at the transmitter (DS90CF384AQ-Q1).

Can you send me the schematic in pdf? It is too blurry to read the pinout when I zoomed in.

Aaron

Thanks for the reply, Aaron.

1. Please verify the pin mapping in the attached schematics. We are using the IC DS90CF384AQ for converting LVDS signals from the processor to RGB signals to LCD. We have followed the pin mapping from the document  SNLA014A (Table 1). confirm the pin mapping is correct for the mentioned application. 

2. kindly review the schematics

3. Need termination resistor value in ohms

4. Need design files for routing reference

5. I have connected the LCD standby pin directly to the MCU without using DS90CF384AQ. Is this correct?

Pin Mapping Verfication.pdf

Hi Arun,

Thank you for sharing the file. I will get back with you by Monday, 2/7.

Aaron

Hi Aaron,

A kind reminder of the below queries

1. Please verify the pin mapping in the attached schematics. We are using the IC DS90CF384AQ for converting LVDS signals from the processor to RGB signals to LCD. We have followed the pin mapping from the document  SNLA014A (Table 1). confirm the pin mapping is correct for the mentioned application. 

2. kindly review the schematics

3. Need termination resistor value in ohms

4. Need design files for routing reference

5. I have connected the LCD standby pin directly to the MCU without using DS90CF384AQ. Is this correct?

Thanks

Arun

Dear Aaron,

Thanks for the reply.

Regarding pin mapping, I have attached the RGB-LCD datasheet. There is no such information Jeida/Vesa format available in the datasheet. I request you to check the attached datasheet of LCD and let us know whether we can use the same pin mapping for this LCD.

Thanks

Arun

TM050RDZG03-00 V5.0.pdf

Hi Arun,

Let me review the datasheet. I will get back with you tomorrow.

Aaron

Hi Arun,

I checked the specs of the panel. It is a RGB panel. The JEIDA and VESA format is only for LVDS mapping. The LVDS mapping is depended on the TX side in order to connect a proper RGB signal. If the incoming format from the TX side is JEIDA, then your connection is correct.

Hope this helps. Let me know if you have further questions.

Aaron

Hi Aaron,

In this design, the processor is the TX board. The LVDS output of the processor is connected to  DS90CF384AQ-Q1, which converts LVDS to RGB signals for the RGB LCD interface. Since I am new to this design, please specify now, where can I check for the JEIDA format?

Arun

Hi Arun,

You need to check with your SoC vendor as it is not allowed me to download the datasheet.

Aaron

Hi Aaron,

Please find the attached datasheet ( LVDS section) for the processor, kindly let us know whether we can use the same pin mapping for this RGB LCD using DS90CF384AQ converter.5277.Processor LVDS section.pdf

Hi Aaron,

Please find the attached datasheet ( LVDS section) for the processor, kindly let us know whether we can use the same pin mapping for this RGB LCD using DS90CF384AQ converter.5277.Processor LVDS section.pdf 

Hi Arun,

Thank you for sharing the specs. I need time to look into this, and I will get back with you on 2/14.

Aaron