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DAC ADC Parallel Interface to go with a Z180 CPU (Z80 or 8080 MPU compatible)

Prodigy 90 points

Replies: 6

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I am looking for a recommendation on a pair of ADC&DAC (not necessarily in one package together) to go with a Z180 CPU (Z80 or 8080 MPU compatible) based computer application.  Basic specifications would be >500kSPS and approximately equivalent in the DAC; 8 bit or higher resolution, no higher then 16 bit although 16 bit itself is acceptable; and an MPU compatible interface i.e. either UART or Parallel data interface; internal reference would be nice but not necessary, and if possible, but again not necessary, DIP mounting type. 

  • Fred,

    I'm not sure I totally follow precisely what you're looking for.

    Do you just want both an ADC and a DAC that can interface your MCU? Do you just want them to share a bus with similar MCU peripheral configuration? This is a bit more unique, but in the past we have seen interests in basically having the ADC directly interface the DAC - is that what you're looking into?

    How many channels of each ADC and DAC do you need?

    Are other interfaces like SPI or I2C available to you?

    Kevin Duke
    DAC Applications Manager

  • In reply to Duke of DACs:

    I want an ADC and a DAC that can interface with the MCU bus and each other but that can be done with a DMA controller or the MCU itself.  I will use up to 4 channels but that can be done with analog switches and S/H circuits if nessacery.  SPI or I2C are not available unless they would happen to be compatible with a UART(which is built in to the Z180 MPU). 

  • In reply to Fred Doe:

    Fred,

    There are not really any simple UART interfaced DACs which could accommodate this. Most of the precision ADC and DAC devices are I2C or SPI interfaced.

    Kevin Duke
    DAC Applications Manager

  • In reply to Duke of DACs:

    I guess I wasn't very clear; either parallel or UART interface is okay for both. 

  • In reply to Fred Doe:

    By the way are there any DACs that have similiar specs to the TLC0820 or ADC0820 ADCs?

  • In reply to Fred Doe:

    Fred,

    It was clear that you were looking for either UART or Parallel interfaces - however I was just indicating that we do not have any UART interfaced DAC devices. I have not seen many native parallel bus peripherals for an MCU which would pair well with DMA - but I will leave the understanding of your MCU peripherals to you - you're the expert in that domain.

    There are 8, 8-bit parallel interfaced precision DAC devices available. You mentioned >500ksps which could put you in either the domain of Precision DACs or High Speed DACs. I only represent Precision DAC. Most of the devices for precision DAC in this category will be un-buffered MDACs, so they can support fairly fast update rates. I just bring up speed since you've pointed to two high-speed ADCs - so maybe we need to refine the ballpark of DACs we're looking at.

    All of the single-channel options are MDACs, which will require an amplifier in a transimpedance configuration at the output. These are TLC7524, DAC0802, DAC0800, and DAC0808.

    There is a very similar story for dual-channel devices, in that they are both MDACs. These are TLC7528 and TLC7628.

    There are two quad-channel options, which are actually both buffered outputs so you can skip the transimpedance requirement I mentioned for the MDACs. TLC7226 and TLC7225.

    Kevin Duke
    DAC Applications Manager