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TPS25751: DRP standby power

Jeff YANG
Mastermind 7755 points
Part Number: TPS25751
Other Parts Discussed in Thread: BQ25792, , BQ25792EVM, TPS25750

Tool/software:

Hi,

May I know the TPS25751D standby current in DRP role? The standyby power consumption can I reference to Ipp5V,sleep(2uA) + Ivin_3V3,Sleep(56uA) = 5*2 + 3.3*56 = 10 + 184.8 = 194.8uW?

Since our device have integrate battery, we concern about the standby power to make sure TPS25751 won't take more power consumption in standby more. Thanks!

Jeff

  • 0
    Mastermind 7755 points

    Hi,

    Another question, I currently plan to add a ship FET, enter shipping mode when off, disconnect the battery power, and use the power key to control QON to turn on the ship FET when powered on. Can the BQ25792 register (SDRV_CTRL[1:0]) be accessed via the TPS25751, or does my Host MCU need to directly read and write the BQ25792 through I2C?

    Thanks!

    Jeff

  • 0 in reply to Jeff YANG
    Mastermind 7755 points

    Hi,

    question 3, if we choose dead battery configuration = AlwaysEnableSink, does there have any reference design can share to us?

  • 0 in reply to Jeff YANG
    TI__Mastermind 34076 points

    Hi Jeff, 

    Jeff YANG said:

    May I know the TPS25751D standby current in DRP role? The standyby power consumption can I reference to Ipp5V,sleep(2uA) + Ivin_3V3,Sleep(56uA) = 5*2 + 3.3*56 = 10 + 184.8 = 194.8uW?

    Since our device have integrate battery, we concern about the standby power to make sure TPS25751 won't take more power consumption in standby more. Thanks!

    Let me double check on this and get back to you tomorrow!

    Jeff YANG said:
    Another question, I currently plan to add a ship FET, enter shipping mode when off, disconnect the battery power, and use the power key to control QON to turn on the ship FET when powered on. Can the BQ25792 register (SDRV_CTRL[1:0]) be accessed via the TPS25751, or does my Host MCU need to directly read and write the BQ25792 through I2C?

    The Host MCU can access this BQ25792 register using 4CC command "I2Cr" to instruct TPS25751 to read a specific register on its I2C master bus line and store the read-back information in TPS25751 DATA1 register. 

    Jeff YANG said:
    question 3, if we choose dead battery configuration = AlwaysEnableSink, does there have any reference design can share to us?

    We do not have any reference design with AlwaysEnableSink enabled, however you can use TPS25751EVM and configure the S1 and S2 switch to be in this DB mode:

    The TPS25751EVM user guide includes specific instructions on how to connect TPS25751EVM with BQ25792EVM for evaluation purposes. Additionally on TPS25751EVM if you remove J16 jumper this will simulate a non-EEPROM PD system (EEPROM is disconnected from PD) and you can use a host MCU launchpad to communicate with the EVMs. 

    Let me know if you have any further questions or concerns! 

    Thanks and Regards,

    Raymond Lin

  • 0 in reply to Raymond Lin
    Mastermind 7755 points

    Hi Raymond,

    The Host MCU can access this BQ25792 register using 4CC command "I2Cr" to instruct TPS25751 to read a specific register on its I2C master bus line and store the read-back information in TPS25751 DATA1 register. 

    => May I know 4CC have any document can share to us? We may consider use it to set BQ25792 enter shipping mode.

    One more question, TPS25751 will turn off BQ25792 watch dog function, right?

    Is possible to enable BQ25792 watch dog via TPS25751?

    Thanks!

  • 0 in reply to Jeff YANG
    Mastermind 7755 points

    Hi Raymond,

    4cc command "I2Cr"  in https://www.ti.com/lit/pdf/slvucr8 in P77-  4.4.3 'I2Cw' - I2C Write Transaction,

    We can use this to set BQ25792 register (SDRV_CTRL[1:0]), right?

    Is there have sample code? After read the document we still can't fully understand the 4cc command operation rule.

    Thanks!

    Jeff

  • 0 in reply to Jeff YANG
    TI__Mastermind 34076 points

    Hi Jeff, 

    Jeff YANG said:
    => May I know 4CC have any document can share to us? We may consider use it to set BQ25792 enter shipping mode.

    Please refer to this text document, this is an example command using the Aardvark adapter with the Control Center program to send I2C commands to TPS25750 (same for TPS25751 as well). 

    I2Cr: 

    Fullscreen 3125.I2Cr_Configuring_BQ25792_IINDPM_Register_Example.txt Download 
    <aardvark>
<configure i2c="1" spi="0" gpio="0" tpower="0" pullups="0"/>
<i2c_bitrate khz="400"/>

<!-- set Aardvark to write to register 0x09 (DATA1) of TPS25750, setting up the I2Cr packet for TPS25750 to read to BQ25792 -->
<!-- 09 refers DATA1 --> 
<!-- 06 refers to the size of this I2C write packet --> 
<!-- 6b refers to the device (Slave) address of the device to read to, in this example 0x6b refers to BQ25792 device address -->
<!-- 06 refers to the device register, in this example 0x06 refers to IINDPM register of BQ25792  -->
<!-- 02 refers to the size of the device register, in thsi example register 0x06 is 2 bytes (refer to BQ25792 datasheet) -->
<i2c_write addr="0x21" count="7" radix="16" nostop="0">09 06 6b 06 02</i2c_write>

<!-- sending I2Cr command to register 0x08 (CMD1) of TPS25750 to execute 4cc command -->
<!-- 08 refers CMD1 -->
<!-- 04 refers to size of this I2C write packet --> 
<!-- 49 32 43 72 decodes to 'I2Cr' from hex to ASCII --> 
<i2c_write addr="0x21" count="6" radix="16" nostop="0">08 04 49 32 43 72</i2c_write>

<!-- Reading the 4 bytes of CMD1 for 00 to indicate command is successfully executed -->
<i2c_write addr="0x21" count="1" radix="16" nostop="0">08</i2c_write>
<i2c_read addr="0x21" count="4"></i2c_read>

<!-- Reading 2 bytes of DATA1 for the output return data from BQ25792 -->
<i2c_write addr="0x21" count="1" radix="16" nostop="0">09</i2c_write>
<i2c_read addr="0x21" count="2"></i2c_read>

</aardvark>

    I2Cw: 
    Fullscreen 3125.I2Cw_Configuring_BQ25792_IINDPM_Register_Example.txt Download 
    <aardvark>

<configure i2c="1" spi="0" gpio="0" tpower="0" pullups="0"/>
<i2c_bitrate khz="400"/>

<!-- set Aardvark to write to register 0x09 (DATA1) of TPS25750, setting up the I2Cw packet for TPS25750 to write to BQ25792 -->
<!-- 09 refers DATA1 --> 
<!-- 06 refers to the size of this I2C write packet --> 
<!-- 6b refers to the device (Slave) address of the device to write to, in this example 0x6b refers to BQ25792 device address -->
<!-- 03 refers to the I2C write packet from TPS25750 when I2Cw is sent -->
<!-- 06 refers to the device register, in this example 0x06 refers to IINDPM register of BQ25792  -->
<!-- 00 C8 sets the IINDPM of BQ25792 to 2000mA, change these two bytes to set different IINDPM -->
<i2c_write addr="0x21" count="7" radix="16" nostop="0">09 06 6b 03 06 00 C8 </i2c_write> 

<!-- Optional Step: Reading register 0x09 to make sure data is setup correctly -->
<i2c_write addr="0x21" count="1" radix="16" nostop="0">09</i2c_write>
<i2c_read addr="0x21" count="6"></i2c_read>

<!-- sending I2Cw command to register 0x08 (CMD1) of TPS25750 to execute 4cc command -->
<!-- 08 refers CMD1 -->
<!-- 04 refers to size of this I2C write packet --> 
<!-- 49 32 43 77 decodes to 'I2Cw' from hex to ASCII --> 
<i2c_write addr="0x21" count="6" radix="16" nostop="0">08 04 49 32 43 77</i2c_write>

<!-- Reading the 4 bytes of CMD1 for 00 to indicate command is successfully executed -->
<i2c_write addr="0x21" count="1" radix="16" nostop="0">08</i2c_write>
<i2c_read addr="0x21" count="4"></i2c_read>

</aardvark>

    Jeff YANG said:

    One more question, TPS25751 will turn off BQ25792 watch dog function, right?

    Is possible to enable BQ25792 watch dog via TPS25751?

    Upon bootup, TPS25751 will disable BQ25792 watchdog timer to prevent any undesired reset on the BQ side. If need to, you can use the EC with I2Cw to TPS25751 (refer to example above) to re-enable BQ25792 WD timer. 

    Jeff YANG said:

    4cc command "I2Cr"  in https://www.ti.com/lit/pdf/slvucr8 in P77-  4.4.3 'I2Cw' - I2C Write Transaction,

    We can use this to set BQ25792 register (SDRV_CTRL[1:0]), right?

    Is there have sample code? After read the document we still can't fully understand the 4cc command operation rule.

    Refer to the attached text file for I2Cw example, the payload for I2Cw input data includes the target device address (BQ25792 slave address), target device register (BQ register), number of bytes to write follow by the actual I2C write to the register. Comments are included in the <!-- --> brackets for additional details on the writes. 

    Jeff YANG said:
    May I know the TPS25751D standby current in DRP role? The standyby power consumption can I reference to Ipp5V,sleep(2uA) + Ivin_3V3,Sleep(56uA) = 5*2 + 3.3*56 = 10 + 184.8 = 194.8uW?

    Regarding your original query on power consumption, this is correct calculation. 

    Let me know if you have any additional questions or concerns! 

    Thanks and Regards,
    Raymond Lin