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PGA460-Q1: PGA460Q-1

Part Number: PGA460-Q1

Hello,

I want to make hardware using PGA460Q-1 for distance measurement. But problem is there if i give 7.5 V in PGA460Q-1 and In MCU 5 V. UART can work with this situation?

1 Reply

  • Dixit,
    Yes, the PGA460 will work with a 7.5V supply at VPWR, and its UART is compatible with 5V logic levels. By the default, the UART is configured for 3.3V logic levels, so you'll need to place a 100kOhm pull-up resistor to 5V at the TEST pin to enable the 5V logic level.

    Here is the excerpt from the datasheet describing this process:

    The digital voltage-level selection performed by the TEST pin is executed at device power up. On power-up, the
    device checks the level of the TEST pin. If the level is low, the digital output pins operate at 3.3 V. If the TEST
    pin is tied high (3.3 V or 5 V are both considered high state), the digital output pins operate at a 5 V. This
    condition is latched in the PGA460-Q1 device so that the test mux can further use the TEST pin as previously
    described. If the application requires that a 5-V digital output is used and a test mux output must be extracted
    from the PGA460-Q1 device, then a weak pullup resistor on the TEST pin can be connected as shown in
    Figure 40.
    As shown in Figure 40, the resistor (RPU) is connected to a permanent power supply and a current path to
    ground is generated through the RPU resistor and the 800-kΩ internal resistance. This configuration is no problem
    for the system; however, it might cause a small quiescent-current increase in applications that require the use of
    the PGA460-Q1 low-power mode to preserve energy. In this case, the TEST pin can be connected to a GPIO pin
    on the external MCU that can output a logic low or high state on the TEST pin to select the voltage level at
    device start-up and later disable the GPIO output to preserve energy or reconfigure the GPIO as an input in case
    the MCU uses any of the PGA460-Q1 test output signals. The external pullup resistor is only required for CMOS
    5-V UART communication and is not required for 3-V communication.
    Akeem Whitehead
    Texas Instruments // ASC-SENSING-SSC // Applications Engineer