• State
  • Locked Locked
  • Replies 6 replies
  • Subscribers 80 subscribers
  • Views 684 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.

MSP430FG6626: ADC within device

Viktorija Cecil
Mastermind 18511 points

Part Number: MSP430FG6626
Other Parts Discussed in Thread: MSP430FG6426, MSP430F47186, MSP430F47183, MSP430F47187

Team, 

Is the ADC within MSP430FG6626IPZ  simultaneous sampling? 

Can you provide more info on what "Continuous-time sigma-delta" means? 

Thanks!

Viktorija

  • 0
    TI__Mastermind 46765 points

    Hi Viktorija,

    It can support simultaneous sampling.

    You can find more detail information about this CTSD16 in the UG chapter 30.https://www.ti.com/lit/ug/slau208q/slau208q.pdf

    "The CTSD16 module consists of up to seven independent sigma-delta analog-to-digital converters, referred to as channels. The converters are based on second-order oversampling sigma-delta modulators and digital decimation filters. The decimation filters are comb-type filters with selectable oversampling ratios of up to 256. Additional filtering can be done in software."

    Best regards

    Cash Hao

  • 0 in reply to Cash Hao11
    Prodigy 70 points

    The device specific datasheet for the MSP430FG6426 states that there is a single sigma-delta ADC does this mean that I can only sample one input at a time and not simultaneously? 

    "The CTSD16 module integrates a single sigma-delta ADC with ten external inputs and four internal inputs.
    The converter is designed with a fully differential analog input pair and a programmable gain amplifier
    input stage. The converter is based on second-order over-sampling sigma-delta modulators and digital
    decimation filters. The decimation filters are comb type filters with selectable oversampling ratios of up to
    256."

  • 0 in reply to Matthew Meadwell
    TI__Mastermind 46765 points

    Hi,

    The sentence you quote is describing the signal chain in figure 9-2. In that figure, it only has one ADC.

    But for the CTSD16 module, it has up to seven independent sigma-delta analog-to-digital converters, referred to as channels. It can do simultaneously sampling.

    Best regards,

    Cash Hao

  • 0 in reply to Cash Hao11
    Prodigy 70 points

    Thank you for the reply.

    My next question is then do I have to manually create register definitions for the header file for the MSP430FG6426?

    Currently I am using IAR embedded workbench and the header file for this specific part only contains registers definitions for a single channel (see text below). So do I have to manually go in and add register definitions for the rest of the channels or is this an error in the header file? Thanks again for all your help.

    Sincerely, 

    Matt

    The below text is copied directly from the msp430fg6426.h header file. As you can see there is only a single channel defined here.

    #define __MSP430_HAS_CTSD16__         /* Definition to show that Module is available */
    #define __MSP430_BASEADDRESS_CTSD16__ 0x0A80
    #define CTSD16_BASE __MSP430_BASEADDRESS_CTSD16__
    #define __MSP430_HAS_CTSD16_0__     /* Definition to show that Module is available */

    #define CTSD16CTL_              (0x0A80u)  /* CTSD16 Control Register 0 */
    DEFCW(  CTSD16CTL             , CTSD16CTL_)
    #define CTSD16IFG_              (0x0AACu)  /* CTSD16 Interrupt Flag Register */
    DEFCW(  CTSD16IFG             , CTSD16IFG_)
    #define CTSD16IE_               (0x0AAEu)  /* CTSD16 Interrupt Enable Register */
    DEFCW(  CTSD16IE              , CTSD16IE_)
    #define CTSD16IV_               (0x0AB0u)  /* CTSD16 Interrupt Vector Register */
    DEFCW(  CTSD16IV              , CTSD16IV_)

    #define CTSD16CCTL0_            (0x0A82u)  /* CTSD16 Channel 0 Control Register */
    DEFCW(  CTSD16CCTL0           , CTSD16CCTL0_)
    #define CTSD16MEM0_             (0x0AB2u)  /* CTSD16 Channel 0 Conversion Memory */
    DEFCW(  CTSD16MEM0            , CTSD16MEM0_)
    #define CTSD16INCTL0_           (0x0A84u)  /* CTSD16 Channel 0 Input Control Register */
    DEFCW(  CTSD16INCTL0          , CTSD16INCTL0_)
    #define CTSD16PRE0_             (0x0A86u)  /* CTSD16 Channel 0 Preload Register */
    DEFCW(  CTSD16PRE0            , CTSD16PRE0_)

    /* CTSD16CTL */
    #define CTSD16REFS            (0x0004u)  /* CTSD16 reference select */
    #define CTSD16CLKR            (0x0008u)  /* CTSD16CLK resistor select */
    #define CTSD16OFFG            (0x0010u)  /* CTSD16 clock fault flag */
    #define CTSD16RRIBURST        (0x0100u)  /* Rail-to-rail input charge pump burst mode request */
    #define CTSD16RRIRDY          (0x0200u)  /* CTSD16 Rail-to-rail input ready */
    #define CTSD16RRIERR          (0x0400u)  /* CTSD16 Rail-to-rail input error */
  • 0 in reply to Matthew Meadwell
    TI__Mastermind 46765 points

    Hi,

    I looked through the device datasheet and found out that MSP430FG6426 only has one CTSD16 channel. In your application, you can look at MSP430F47183 with 3 sigma delta ADC, MSP430F47186 with 6 sigma delta ADC or MSP430F47187 with 7 sigma delta ADC.

    Best regards,

    Cash Hao

  • 0 in reply to Cash Hao11
    Prodigy 70 points

    Hi,

    Thank you for the clarification and all your assistance on this topic. Have a great day.

    Thanks,

    Matt

**Attention** This is a public forum