PSoC 5, 3 & 1 MCU

[WAHA_1607076]

Hello,

When using VDAC on the CY8CKIT-059 powered at 5.0V.   VDDIO measured to be 5.0V.

When I set the value of 0xff0 the max out for 12bit mode..  I can only get 3.3V out.  No load on the output pin.

Tried different pins all are 3.27 to 3.3 V out.

I set the DAC to 1.020 range.  It's max voltage out is .8V.

Here is the code..

#include "project.h"

int main(void)

{

    CyGlobalIntEnable; /* Enable global interrupts. */

    /* Place your initialization/startup code here (e.g. MyInst_Start()) */

VDAC_Start();

Opamp_Start();

// Set VOUT to 4.080V

VDAC_SetValue(0xff0);  // P0.1

    for(;;)

    {

        /* Place your application code here. */

    }

}

/* [] END OF FILE */

I'm not sure why I am not seeing 4.080 ...  any ideas?

Thanks,
Wayne

[Len_CONSULTRON]

Wayne,

If I am correct, analog components work off the VDDA voltage domain.  On the CY8CKIT-059, VDDA = 5V- one schottky diode drop from the KitProg board (D1).  Therefore, the max voltage in the natural state of the CY8CKIT-059 is about 4.75V.

Questions:

• What is the resistor-equivalent load on Vout?
• The PSoC5LP has two 8-bit VDACs.  To achieve a 12-bit, you must be using the Dithering VDAC.  In this case, are you using the cap recommended to stabilize the VDAC voltage to smooth the dithering signal?

Len

[WAHA_1607076 · Accepted solution]

Sorry Folks...  it's working now..

Seems I had a faulty connection to the power supply..