• State Resolved
  • Locked Locked
  • Replies 2 replies
  • Subscribers 19 subscribers
  • Views 734 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

CC1101 AVDD and DVDD separation for low power?

Maurizio Brignoli
Prodigy 140 points

Other Parts Discussed in Thread: CC1101, TPS62730

Dear TI E2E Community,

 I don't find on Datasheet what AVDD ad DVDD pin supply internally to the chip. My target is to reduce as much as possible the battery consumption.

My idea is to separate AVDD with 2,1V and DVDD with 3,3V same as MCU (fixed);

My question are:

1) After chipset inizialization (write), may I switch off 2,1V AVDD to reduce the battery power consumption (during sleep mode of mcu) and keep the register contenents? 

2) When the mcu wakeup, and processing need to transmit data may I switch on 2,1V AVDD and strobe in TX mode the CC1101?

Is there any wrong procedure in the 2 steps to save the battery consumption?

3) There are some advantages separating AVDD and DVDD for the point of view of power consumption if i can switch off 2,1V?

Unfortunatly it is impossible separate on CC1101EVM AVDD and DVVD to test if there any reduction in power consumption.

Is there any document not listed under CC1101 Application Note that can explain better AVDD and DVDD difference?

Thank you

  • 0
    TI__Guru**** 317180 points

    I would not recommend running DVDD and AVDD on different potential since the chip is not designed for this.

    DVDD supplies the digital part of CC1101, AVDD the radio part.

    A level difference between the parts could affect the timing in the analog- digital interface. The interface is not designed for 2.1V to/from 3.3V which could result in logic '1' outside spec and increased power consumption. 

    Since the chip is not designed with a voltage difference between the domains in mind it is also a risk for a P-N junction somewhere to start conduct.

    To save current running both CC1101 and the MCU on a DC-DC could be a better idea.

  • 0 in reply to TER
    TI__Mastermind 39860 points

    CC1101 data sheet, page 7, table 1 and table 2: "Absolute maximum ratings" and "Operation conditions" respectively explicitly states that all supply pins must have the same voltage.

    Refer to page 3 in the CC1101 data sheet for current consumption figures when using CC1101 + TPS62730 dc-dc converter