# How high voltage should be set for VREF and VCCD on CY8C4248LQI-BL583? on spec, they are 1.024V and 1.8V, respectively, but measured values are ~0.0 for both.

Anonymous
Not applicable

Hi, can any expert answer my question? Thanks!

How high voltage should be set for VREF and VCCD on CY8C4248LQI-BL583? on spec, they are 1.024V and 1.8V, respectively, but measured values are ~0.0 for both.

1 Solution

# Re: How high voltage should be set for VREF and VCCD on CY8C4248LQI-BL583? on spec, they are 1.024V and 1.8V, respectively, but measured values are ~0.0 for both.

Anonymous
Not applicable

If you are measuring 0 volts, it sounds like the board isn't powered/working correctly?

From the spec VREF is 1.024v from an internal regulator, and VCCD is also regulated to 1.8v like you stated. Although, the VCCD mentions needing a 1uF cap for stabilizing the power supply...

The datasheet has the wiring for an example powered board on page 16 with the capacitor and pins wired up for an example schematic. Perhaps that will help?

3 Replies

# Re: How high voltage should be set for VREF and VCCD on CY8C4248LQI-BL583? on spec, they are 1.024V and 1.8V, respectively, but measured values are ~0.0 for both.

Anonymous
Not applicable

If you are measuring 0 volts, it sounds like the board isn't powered/working correctly?

From the spec VREF is 1.024v from an internal regulator, and VCCD is also regulated to 1.8v like you stated. Although, the VCCD mentions needing a 1uF cap for stabilizing the power supply...

The datasheet has the wiring for an example powered board on page 16 with the capacitor and pins wired up for an example schematic. Perhaps that will help?

# Re: How high voltage should be set for VREF and VCCD on CY8C4248LQI-BL583? on spec, they are 1.024V and 1.8V, respectively, but measured values are ~0.0 for both.

Anonymous
Not applicable

Thank you very much! This is very helpful.

Anonymous
Not applicable

You are welcome