• State TI Thinks Resolved
  • Locked Locked
  • Replies 5 replies
  • Answers 1 answer
  • Subscribers 47 subscribers
  • Views 661 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

DAC5652A: Pulse response

NAOKI AOYAMA
Guru 11215 points
Part Number: DAC5652A

Hello,

Our customer use the DAC5652A.

The customer estimate the output voltage of the DAC5652A with pulse response.

There is about 5mV difference between pulse response and DC.

Could you tell me what is wrong? or the difference is reasonable?

The configuration of the customer as follows.

Vref : 1.25V external reference by LDO

RSET: 2.1 kohm

IOUT_FS = 19mA , VOUT_FS = 474mV

Single ended 24.9 ohm terminated , both IOUT1 and IOUT2

MODE:H

GSET:H

Circuit: DAC5652A, temination resistor, OPAMP

Of course, I asked the customer to estimate without OPAMP. But, result is no change.

I checked the PCB layout of the customer. The distance DAC5652A and OPAMP is less than 15mm.

There is no capacitor parts and stray capacitor.

I attach the scope shot.

DAC5652A_pulse_response.pdf

Best Regards,

Naoki Aoyama

  • 0
    TI__Guru* 91947 points

    Naoki,

    Someone will get back with shortly regarding this.

    Regards,

    Jim

  • 0 in reply to jim s
    Guru 11215 points
    Hello Jim,

    Is there any update?

    Regards,
    Naoki Aoyama
  • 0 in reply to jim s
    Guru 11215 points
    Hello,

    Is there anybody here?

    Is it possible to obtain the settling performance using a single-ended output?

    Regards,
    Naoki Aoyama
  • 0 in reply to NAOKI AOYAMA
    TI__Guru* 91947 points

    Naoki,

    Your request is in our queue. Someone will look into this shortly. Can you explain a little more about the setup? Is the 5mV offset the difference when the DAC input code is at a constant value vs when the pulse is at a logic low code value? The screen shots look like the pulse has an offset as well. How do these plots compare to the DAC output when the input data is at all "0" or full scale? Does the offset change if the pulse period changes? What is the pulse digital values going into the DAC? Can you please tell us what the application is for?

    Regards,

    Jim

  • 0 in reply to jim s
    Guru 11215 points
    Hello Jim,

    Thank you for your reply and support.
    I describe the setting of the customer as follows,

    2E5h ---------- 0B2h ----------- 3FFh (digital input code)
    343mV 82.4mV 474mV (calculate from setting)

    342.2mV 84.1mV 471.4mV (DC results)
    346.3mV 90.4mV 465.2mV (pulse response)

    (1LSB = 0.463mV)

    I can not open the application of the customer at this post.
    But the customer need making a pulse voltage.

    I will ask the customer to estimate with pulse period change.

    Best Regards,
    Naoki Aoyama