NB669GQ-Z datasheet by Monolithic Power Systems

NB669GQ-Z Frequently Asked Questions (FAQs)

• What is the recommended PCB layout for optimal performance?
  A good PCB layout is crucial for the NB669GQ-Z. Ensure that the input and output capacitors are placed close to the IC, and the power traces are wide and short. Also, keep the sensitive analog signals away from the switching node and use a solid ground plane to reduce noise and EMI.
• How do I choose the right input and output capacitors?
  Choose input capacitors with low ESR and high ripple current rating. For output capacitors, select ones with low ESR, high capacitance, and a voltage rating that meets or exceeds the output voltage. The datasheet recommends a minimum of 10uF for the input capacitor and 22uF for the output capacitor.
• What is the maximum ambient temperature for reliable operation?
  The NB669GQ-Z is rated for operation up to 85°C ambient temperature. However, it's recommended to derate the output current and ensure good airflow to maintain a safe junction temperature (TJ) below 125°C.
• How do I implement overcurrent protection (OCP) and short-circuit protection (SCP)?
  The NB669GQ-Z has a built-in OCP and SCP. To implement these features, connect the OCP pin to a resistor divider network that sets the current limit. For SCP, connect the SCP pin to a resistor that sets the short-circuit detection threshold. Refer to the datasheet for specific implementation details.
• What is the recommended input voltage range for optimal performance?
  The NB669GQ-Z can operate with input voltages from 2.7V to 5.5V. However, for optimal performance, it's recommended to operate within the 3.3V to 4.2V range to ensure high efficiency and low dropout voltage.