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Single ended to differential mic signal driver recommendations

Category: Hardware
Product Number: e.g. LTC6363, LT6350

Anyone have recommendations for single ended to unity-gain differential signal drivers for microphone signals at low output impedance, noise, and quiescent current (<5mA)? I see some chips like LTC6363-1 and LT6350 but these indicate SAR optimization. My application would interface with a downstream ADC/preamp which I presume falls into sigma-delta category. Would these types of chips by an issue? Looking for compact solution that eliminates delays, cascading noise, etc. Thanks in advance for any input.

clarified ADC interface type
[edited by: Kapila at 7:16 PM (GMT -4) on 17 May 2023]
  • Hello Kapila,

    You kind of are describing two different applications. An ADC will usually require an input level that is higher than a mic level signal. Although it does depend on what the AVDD voltage the part is operating on. Our newer parts that run on 1.8V require a small signal as a full-scale input. 

    I captured this circuit from the AD1938 datasheet. It is an older design and you will probably not like the way it inverts. 

    It is meant to drive an ADC with a 3.3V power rail that is sitting up at around a 1.5V common mode voltage. This is a very common circuit and can be a good starting point. 

    Even though this is a good audio question, you are probably better to ask this on the linear amplifiers section of the forum. (+) Amplifiers - EngineerZone (

    I think they should be able to help and also try searching that forum space for answers.

    Dave T

  • Hi Dave, thanks for the input. I'll be sure to check out your suggestions.