BD71847AMWV-E2 - ROHM Semiconductor

BD71847AMWV-E2 Frequently Asked Questions (FAQs)

• What is the recommended PCB layout for optimal thermal performance?
  ROHM recommends a 4-layer PCB with a thermal relief pattern on the bottom layer to improve heat dissipation. A minimum of 2oz copper thickness is recommended for the top and bottom layers.
• How do I ensure the PMIC's power-up sequence is correct?
  The BD71847AMWV-E2 has a specific power-up sequence requirement. Ensure that the input voltage (VIN) is applied before the enable signal (EN) is asserted. Also, ensure that the voltage rails are powered up in the correct sequence (e.g., core voltage before I/O voltage).
• What is the maximum capacitance value for the output capacitors?
  The maximum capacitance value for the output capacitors depends on the specific output rail. For the core voltage (VDD_CORE), a maximum capacitance of 22uF is recommended. For the I/O voltage (VDD_IO), a maximum capacitance of 10uF is recommended.
• How do I handle the thermal shutdown feature?
  The BD71847AMWV-E2 has a built-in thermal shutdown feature that triggers when the junction temperature exceeds 150°C. When this occurs, the PMIC will shut down and restart when the temperature drops below 120°C. Ensure that your system design can handle this shutdown and restart sequence.
• What is the recommended input capacitor value for the VIN pin?
  ROHM recommends a minimum input capacitance of 10uF to ensure stable operation. A larger capacitance value (e.g., 22uF) can be used for improved noise filtering and transient response.