• State TI Thinks Resolved
  • Locked Locked
  • Replies 1 reply
  • Answers 1 answer
  • Subscribers 63 subscribers
  • Views 721 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.

TPS65217: TPS65217 power up configuration

Gabriel Xu
Intellectual 2145 points
Part Number: TPS65217

Hi IPM teams

This is Gabriel Xu from South China OEM team, nice to meet you.

My customer is plan to used TPS65217 in their new design and I have few technical question want to confirm with application team.

Customer system only have one MCU and this MCU is plan to power by our PMIC. It means that no I2C communication can be executed before the PMIC 3.3V power rails is ready for the MCU.

My question:

  1. As their MCU need 3.3V/300mA power supply, are TPS65217C/D (LS4 default as LDO and default output voltage is 3.3V) can power up without MCU’s control when a AC power is plug in?
  2. I found in 0x16H register, all DC-DC/LDO enable signal default value is disable. Could our PMIC power up without enabling these bit?
  3. Register 0x16 is the enable control of all DC-DC and LDO, but the default value of this register is all "disable" the output? Could the PMIC power up with default configuration under this condition?

Thanks in advance.

  • 0
    TI__Mastermind 30280 points

    Gabriel Xu said:
    As their MCU need 3.3V/300mA power supply, are TPS65217C/D (LS4 default as LDO and default output voltage is 3.3V) can power up without MCU’s control when a AC power is plug in?

    By default, only LDO1 (1.8V) can power-on before the PWR_EN input signal goes high. It is assigned to Strobe 15, as you can see in Section 5 Device Comparison Table on page 4 of the TPS65217 datasheet.

    Gabriel Xu said:
    I found in 0x16H register, all DC-DC/LDO enable signal default value is disable. Could our PMIC power up without enabling these bit?

    The entire power sequence of the TPS65217 PMIC will execute if the PWR_EN pin is permanently pulled high. The PWR_EN pin has an Abs Max of 7V and will easily operate if it is pulled up to an input voltage of 5V through a resistor. For enabling and disabling of the DC-DC converter and LDOs, I2C is not required. The PMIC follows the sequence in Registers 0x19-0x1E (SEQ1-5) automatically set the bits in Reg. 0x16 to 1b in order according to the sequence.

    Register 0x16 is not backed by EEPROM. These bits are controlled in a run-time environment, first automatically by the sequencer and then can be controlled manually by the MCU (or processor) when the PMIC is in the ACTIVE state. But this register will always reset to a value of 0x00.

    Registers 0x19-0x1E (SEQ1-5) are backed by EEPROM and the reset values will be non-zero to control the timing of the power-on sequence.

    The only benefit of toggling the PWR_EN pin low in the run-time environment is to be able to put the PMIC in the SLEEP or OFF states to conserve battery life in a portable application, as shown in Figure 24. Global State Diagram on page 39 of the datasheet. Pulling the PWR_EN pin high to the input voltage of 5V all the time is acceptable in an application where power savings are not a strict requirement because the PMIC will be fully on as soon as AC or USB is applied.