• State Resolved
  • Locked Locked
  • Replies 1 reply
  • Subscribers 46 subscribers
  • Views 517 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.

Selecting an amplifier to drive a 4-ch, 24-bit audio ADC

Karen
Intellectual 940 points
Other Parts Discussed in Thread: THS4524, THS4522, ADS1278, THS4521

I am designing an audio system and am looking for an amplifier to drive the differential inputs on my 4-ch, 24-bit audio ADC. The specifications I am most interested in on the ADC are dynamic range of 115dB, THD+N of -102dB, and channel separation of 120dB. The system has a tight power budget, so low power is essential. Does TI have an input amplifier for my application?

  • 0
    TI__Intellectual 940 points

    TI just introduced the THS4521 (single), THS4522 (dual), and THS4524 (quad) family of low power, high performance fully differential amplifiers that are targeted at driving SAR and Delta-Sigma ADCs in many applications including audio. Its performance should match well with your goals and provide a very low power solution with each amplifier drawing about 1mA quiescent current with single 5V supply. To Illustrate the performance that can be achieved, we tested the THS4521 with the ADS1278 24-bit Delta-Sigma ADC, and results are shown in the application section of the data sheet (http://focus.ti.com/docs/prod/folders/print/ths4521.html). While the ADS1278 is targeted at industrial applications, its performance in the audio band is very good. Testing showed 114dB dynamic range (SFDR), and -106dB THD+N (SINAD). The THS4521 is a single device and channel separation will be dictated mostly by the circuit board layout and power supply decoupling, but 120dB is easily achieved. The THS4522 dual and THS4524 quad devices have channel separation (crosstalk) that is better than 120dB throughout the audio band.