T1040 RCW EVDD_VSEL field

[zoyakhmelnik]

The T1040 RCW has the EVDD_VSEL field that configures  the voltage of the EVDD IO domain and selects 1.8V or 3.3V. We accidentally had configured it to 1.8V while actually the EVDD is connected to 3.3V. What this configuration does affect ? What problems such mismatch can cause ?

[ufedor]

Recommendation is to use the correct RCW settings.

When you provide 1.8V supply and set VSEL to 3.3V, the Vih of the signal may go outside the range for 3.3V+-5% tolerance.

Also the device may fail to boot if the boot device (SPI/SD) is not at the correct voltage.

On the other hand if VSEL is at 1.8V and you provide 3.3V as supply, it may damage the I/O's.

[zoyakhmelnik]

Thank you for fast and useful answer.

Regards,

Zoya Khmelnik

NSD, ECI Telecom Ltd.

office: 03-926-8728

mobile: 052-8799405

Zoya.Khmelnik@ecitele.com<mailto:Zoya.Khmelnik@ecitele.com>