Design Inquiry

Hi AbhishekManoj 

1. It is generally a good practice to not leave the unused serial interface pins floating. It is recommended to terminate them (for example, with 10k resistor to ground).

2. The resistor values stated in table 9 are the internal resistors as shown in Figure 69. So, you only need the external capacitors.

3. C31 and C32 should be connected to the VCMx paths. So, for the second amplifier, the capacitor should be connected to the +IN pin as well.

Hope this helps.

Regards,
Flynn

Hi FlynnEdmund 

Thanks for the reply. Please address the below more queries regarding AD3551R, single channel DAC.

1.Why LDAC and RESET# is shorted as a single IO in evaluation board.

2.I'm using AD3551R, single channel DAC, can i refer the AD3552R evaluation for AD3551R also as i couldn't find any AD3551R evaluation board.

3.The RFB values for single channel DAC AD3551R, can i choose the values for RFB capacitor values for AD3552R.

Regards,

Abhishek

Hi FlynnEdmund 

Thanks for the reply.

Does it is mandatory to short LDAC and RESET pins or i can use as a seperate pins to FPGA.

Regards,

Abhishek

Hi AbhishekManoj ,

No, it is not mandatory to short LDAC and RESET pins. You can assign them on separate FPGA pins.

Regards,
Flynn

Hi FlynnEdmund 

In datasheet, it is mentioned as

In my board -Vs is -12V, should i connect it to -12V or to ground.

Regards,

Abhishek

Hi AbhishekManoj 

The datasheet is correct. You should connect the exposed pad to -Vs.

Regards,
Flyn

Hi FlynnEdmund and team,

I'm attaching my schematics of DAC AD3552R and AD3551R.

Request you to review and provide the feedbacks.

1.AD3551R and AD3552R interfaced with OPA4192 amplifier.

Does the schematics works fine?

PDF

2.AD3552R interfaced with AD8676ARMZ and with isolation transformer 78601/9JC-R. 

Does the resistor, capacitor values of the circuits are fine?

PDF

Regards,

Abhishek

Hi Team,

Please provide an update on above.

Regards,

Abhishek

Hi AbhishekManoj 

Both schematics seem fine.
The values of the resistors and capacitors are fine as well but if you can add some leeway for adjustments based on your application, it would be best.

Regards,
Flynn

Hi FlynnEdmund 

Thanks for the confirmation.

In my board I'm planning to give EMI shield (RF Cage) to all my DACs separately. While selecting the cage for AD3551R and AD3552R, is there any recommendations for the spacing from DAC IC or height anything like that.

Also the RF cage must be provided for the DAC including its surrounding components. Does the cage to be provided for DAC output amplifiers also.

Regards,

Abhishek

Hi Team,

Please provide an update on above.

Regards,
Abhishek

Hi Team,

Please provide an update on above.

Regards,
Abhishek

Hi Team,

Please provide an update on above.

Regards,
Abhishek