• State Resolved
  • Locked Locked
  • Replies 3 replies
  • Subscribers 46 subscribers
  • Views 333 views
  • Users 0 members are here
Support feedback
Options
Options
Related

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.

DAC7744: Is it possible to use VCC=5V and VSS=-5V

Shinichi Inoue
Guru 21566 points
Part Number: DAC7744
Other Parts Discussed in Thread: DAC7644,

Dear Specialists,

My customer is considering DAC7744 instead of DAC7644.

I would be grateful if you could advise.

---

Since DAC7644 is difficult to obtain, we are considering whether DAC7744 can be used.

The two devices are pin compatible and have different supply voltages VCC and VSS.

The electrical characteristics of the DAC7744 are specified at VCC=15V±0.75V and VSS=-15V±0.75V.

Is it possible to operate  with VCC=5V±0.25V and VSS=-5V±0.25V the same as DAC7644?

What happens to the electrical characteristics when operated under these conditions?

Will it be the same as DAC7644?

---

I appreciate your great help in advance.

Best regards,

Shinichi

  • 0
    TI__Mastermind 41573 points

    Hi Shinichi-san, 

    I am checking this now and will get back to you shortly. 

    Best,

    Katlynne Jones

  • +1 in reply to Katlynne Jones
    TI__Mastermind 41573 points

    Hi Shinichi-san,

    I reviewed the datasheet in more detail and it does not look like the DAC7744 can operate with ±5V supplies. The part itself was designed to work at the higher supply range only. 

    The electrical characteristics table mentions the maximum and minimum supplies:

    Later in the datasheet, it mentions that a negative supply other than -15V or ground can cause improper operation. It also looks like this device has a greater headroom requirement of 4V while the DAC7644 requires 2.25V of headroom. That likely won't work for the customer's application based on a 5V supply. 

    Best,

    Katlynne Jones 

  • 0 in reply to Katlynne Jones
    Guru 21566 points

    Hi Katlynne,

    Thank you for your reply.

    I understand DAC7744 could not use for +/-5V supply.

    I'll share with the customer.

    I appreciate your great help and cooperation.

    Best regards,

    Shinichi