PN5190 individual Voltage Supply for VBAT & VBATPWR

[Dan112]

Could you Please tell me about the voltage supply methods for VBAT and VBATPWR when using the internal DC-DC of PN5190?

①Is it okay to input different voltages to VBAT and VBATPWR?
　Are there no constraints on the relationship between VBAT and VBATPWR, so both inputs in the example below should be acceptable?

　[Example1] VBAT=3.3V, VBATPWR=4.0V
　[Example2] VBAT=3.3V, VBATPWR=3.0V

②If different voltage power sources are input to VBAT and VBATPWR, is it acceptable for VBATPWR to drop below VDDIO as long as it remains within the range of 2.8 to 4.8V?

[KellyLi]

Hello @Dan112 

①Is it okay to input different voltages to VBAT and VBATPWR?
VBAT: System supply, used to supply the analog and digital blocks,memory and internal voltage references.
VBATPWR: To be connected to boost inductor and transmitter power supply, which input value will affect the output of RF transmitter, like VDDPA and VDD_TX.
GPIO's functionality, host interface and internal analog and digital blocks are independent of the RF driver supply. This allows VBAT and VBATPWR to be powered independently, making it easy to configure a dedicated transmitter supply configuration at any time.
That is to say, VBAT and VBATPWR can be connected to different input sources, as long as they are within the allowable range and meet the requirements of your application, which here are mainly for the performance of the TX output.

②If different voltage power sources are input to VBAT and VBATPWR, is it acceptable for VBATPWR to drop below VDDIO as long as it remains within the range of 2.8 to 4.8V?
VDDIO is Supply for the host interface and GPIO's, its reference source is VBAT. VDDIO must always be smaller or equal to the VBAT.

[Dan112]

Thank you for your response. @KellyLi 
It is mentioned that VBAT is used for analog and digital blocks, as well as internal voltage references.

Would there be any impact on the Tx output or reception performance when VBAT fluctuates?
For example,
① Even if VBATPWR is constant, does fluctuation in VBAT affect the transmission signal level?
② Would fluctuation in VBAT impact the A/D conversion of the received signal or the decoding process?

[KellyLi]

Hello @Dan112 

If VBAT and VBATPWR come from different sources, then fluctuations in VBAT will not affect TX.
However, the digital and analog blocks are supplied from VBAT, so fluctuations in VBAT will affect the A/D conversion.