LFD21891MMF3D931 - Murata Electronics

LFD21891MMF3D931 Frequently Asked Questions (FAQs)

• What is the recommended land pattern for this inductor?
  Murata recommends a land pattern with a minimum pad size of 2.5mm x 1.5mm and a non-solder mask defined (NSMD) pad shape to ensure reliable soldering and minimize thermal resistance.
• How do I handle the inductor's thermal derating?
  The LFD21891MMF3D931 has a maximum operating temperature of 125°C. To ensure reliable operation, derate the inductor's current rating by 1.5% per degree Celsius above 80°C. Consult the datasheet for detailed derating curves.
• What is the inductor's self-resonant frequency (SRF)?
  The SRF of the LFD21891MMF3D931 is typically around 150 MHz to 200 MHz, but this value can vary depending on the specific application and PCB layout. It's essential to consider the SRF when designing the circuit to avoid unwanted resonances.
• Can I use this inductor in a high-vibration environment?
  The LFD21891MMF3D931 is designed to withstand moderate vibration levels. However, if your application involves extreme vibration, shock, or mechanical stress, consider using a more robust inductor or additional mechanical support to ensure reliability.
• How do I ensure the inductor's magnetic shielding?
  To minimize electromagnetic interference (EMI), ensure that the inductor is placed at least 1 mm away from other components and that the PCB layout does not create a magnetic loop. You can also use a magnetic shield or a mu-metal shield to further reduce EMI.