CYW920719 User Guide states "VDDIO must be greater or equal to VBAT". Why the note?

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GrCa_1363456
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CYW920719 User Guide states "VDDIO must be greater or equal to VBAT" in a note on page 29 at the end of Section 3.2, reference http://www.cypress.com/file/411346/download.

This Note contradicts the possible settings for VDDIO and VBAT stated in Table 12 of the CYW20719 datasheet which allows VDDIO to be as low as 1.76v while VBAT can only drop to 1.9. Reference CYW20719 data sheet @ http://www.cypress.com/documentation/datasheets/cyw20719-enhanced-low-power-bredrble-bluetooth-50-so...

It appears from the data sheet that VDDIO and BAT are independent - is this not true?

Why the note?

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MichaelF_56
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user_455868498

I checked internally and this constraint no longer exists in the latest B1 rev. of the chip.

Essentially, the chip designer updated the circuit with voltage translator internally so that we can now support VDDIO<VBAT now.

The condition for VDDIO>=VBAT still applies to 20735 and 20719B0.

We are in the process of updating the spec. 

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MichaelF_56
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user_455868498

I checked internally and this constraint no longer exists in the latest B1 rev. of the chip.

Essentially, the chip designer updated the circuit with voltage translator internally so that we can now support VDDIO<VBAT now.

The condition for VDDIO>=VBAT still applies to 20735 and 20719B0.

We are in the process of updating the spec.