TMS320F28377D ADC measurement time

Hello,

Please let me know how I can obtain the ADC result under per 1us.
ADC clock is 33.2MHz and the acquisition window is 75ns.
I want to get the result under per 1us, however I can't.

I use the following setting and code.

ADC = ADC D
CPU clock = 199.2 MHz

- ADC settings
void ConfigureADC(void)
{
    EALLOW;

    // Using DAC ,configure ADCA - C

    //write configurations
    AdccRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4
    AdcdRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4

    AdcSetMode(ADC_ADCC, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);
    AdcSetMode(ADC_ADCD, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);

    //Set pulse positions to late
    AdccRegs.ADCCTL1.bit.INTPULSEPOS = 1;
    AdcdRegs.ADCCTL1.bit.INTPULSEPOS = 1;

    //power up the ADCs
    AdccRegs.ADCCTL1.bit.ADCPWDNZ = 1;
    AdcdRegs.ADCCTL1.bit.ADCPWDNZ = 1;

    //delay for 1ms to allow ADC time to power up
    DELAY_US(1000);

    EDIS;
}

void SetupADCSoftware(void)
{
    Uint16 acqps;

    //determine minimum acquisition window (in SYSCLKS) based on resolution
    if ( ADC_RESOLUTION_12BIT == AdcdRegs.ADCCTL2.bit.RESOLUTION )
    {
        acqps = 14;     //75ns
    }
    else
    { //resolution is 16-bit
        acqps = 63;     //320ns
    }
    EALLOW;
    //Select the channels to convert and end of conversion flag
    //---------------------------------------------------------------------
    //  ADC C
    //---------------------------------------------------------------------
    //  signal              pin
    //----------------------------------
    //  TP10/TP2            ADCINC2
    //  TP10/TP3            ADCINC3
    //  TP10/TP4            ADCINC4

    AdccRegs.ADCSOC0CTL.bit.CHSEL = 2;              //SOC0 will convert pin C2
    AdccRegs.ADCSOC0CTL.bit.ACQPS = acqps;          //sample window is acqps + 1 SYSCLK cycles
    AdccRegs.ADCSOC1CTL.bit.CHSEL = 3;              //SOC1 will convert pin C3
    AdccRegs.ADCSOC1CTL.bit.ACQPS = acqps;          //sample window is acqps + 1 SYSCLK cycles
    AdccRegs.ADCSOC2CTL.bit.CHSEL = 4;              //SOC2 will convert pin C4
    AdccRegs.ADCSOC2CTL.bit.ACQPS = acqps;          //sample window is acqps + 1 SYSCLK cycles

    AdccRegs.ADCINTSEL1N2.bit.INT1SEL = 2;          //end of SOC2 will set INT1 flag
    AdccRegs.ADCINTSEL1N2.bit.INT1E = 1;            //enable INT1 flag
    AdccRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;          //make sure INT1 flag is cleared
    //---------------------------------------------------------------------
    //  ADC D
    //---------------------------------------------------------------------
    //  signal              pin
    //----------------------------------
    //  ADC_THERM_1         ADCIND0
    //  ADC_THERM_2         ADCIND1
    //  ADC_THERM_3         ADCIND2
    //  ADC_THERM_4         ADCIND3
    //  ADC_CURRENT_MEG     ADCIND4

    // ADC_THERM_1 - 4
    AdcdRegs.ADCSOC0CTL.bit.CHSEL = 0;  //SOC0 will convert pin D0
    AdcdRegs.ADCSOC0CTL.bit.ACQPS = acqps; //sample window is acqps + 1 SYSCLK cycles
    AdcdRegs.ADCSOC1CTL.bit.CHSEL = 1;  //SOC1 will convert pin D1
    AdcdRegs.ADCSOC1CTL.bit.ACQPS = acqps; //sample window is acqps + 1 SYSCLK cycles
    AdcdRegs.ADCSOC2CTL.bit.CHSEL = 2;  //SOC2 will convert pin D2
    AdcdRegs.ADCSOC2CTL.bit.ACQPS = acqps; //sample window is acqps + 1 SYSCLK cycles
    AdcdRegs.ADCSOC3CTL.bit.CHSEL = 3;  //SOC3 will convert pin D3
    AdcdRegs.ADCSOC3CTL.bit.ACQPS = acqps; //sample window is acqps + 1 SYSCLK cycles
    // ADC_CURRENT_MEG
    AdcdRegs.ADCSOC4CTL.bit.CHSEL = 4;  //SOC4 will convert pin D4
    AdcdRegs.ADCSOC4CTL.bit.ACQPS = acqps; //sample window is acqps + 1 SYSCLK cycles

    AdcdRegs.ADCINTSEL1N2.bit.INT1SEL = 3; //end of SOC3 will set INT1 flag
    AdcdRegs.ADCINTSEL1N2.bit.INT1E = 1;   //enable INT1 flag
    AdcdRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; //make sure INT1 flag is cleared

    AdcdRegs.ADCINTSEL1N2.bit.INT2SEL = 4; //end of SOC4 will set INT2 flag
    AdcdRegs.ADCINTSEL1N2.bit.INT2E = 1;   //enable INT2 flag
    AdcdRegs.ADCINTFLGCLR.bit.ADCINT2 = 1; //make sure INT2 flag is cleared
}

- ADC measurement
    while (1)
    {
        //convert, wait for completion, and store results
        //start conversions immediately via software, ADCD
        AdcdRegs.ADCSOCFRC1.all = 0x0010; // SOC4

        //wait for ADCD to complete, then acknowledge flag
        while (AdcdRegs.ADCINTFLG.bit.ADCINT2 == 0);
        AdcdRegs.ADCINTFLGCLR.bit.ADCINT2 = 1;

        //store results
        AdcdResult4 = AdcdResultRegs.ADCRESULT4;

        strcat(mesRetBuff, "RESULT:");
        ltoa(AdcdResult4, temp);
        sprintf(temp, "%5d", AdcdResult4);
        strcat(mesRetBuff, temp);
        strcat(mesRetBuff, "\n");

        while (USBBufferSpaceAvailable(&g_sTxBuffer) < strlen(mesRetBuff));

        USBBufferWrite((tUSBBuffer *) &g_sTxBuffer, (uint8_t *) &mesRetBuff,
                strlen(mesRetBuff));

        // clear　mesRetBuff
        memset(mesRetBuff, '\0', strlen(mesRetBuff));
        memset(temp, '\0', strlen(temp));

        if ( g_MesCurBreak )
        {
            g_MesCurBreak = 0;
            break;
        }
    }

Best Regards,

Nomoto