Instructions for Use

1. Input Voltage (V_IN):

   • Ensure the input voltage is within the range of 2.5V to 40V.
   • Use appropriate input capacitors to stabilize the input voltage.

2. Output Voltage (V_OUT):

   • The output voltage can be adjusted using external resistors.
   • Connect the feedback pin (FB) to the output through a resistor divider to set the desired output voltage.

3. Output Current (I_OUT):

   • The maximum continuous output current is 3A.
   • Ensure adequate heat sinking if operating at high currents to maintain efficiency and prevent overheating.

4. Quiescent Current (IQ):

   • The quiescent current is typically 2.5mA when the input voltage is 5V.
   • This value helps in estimating the power consumption of the device.

5. Shutdown Current (ISD):

   • The shutdown current is typically 1μA when the shutdown pin (SHDN) is pulled low.
   • Use this feature to conserve power in battery-operated systems.

6. Switching Frequency (f_SW):

   • The typical switching frequency is 1.2MHz.
   • This high frequency allows for smaller external components but may increase switching losses.

7. Efficiency (η):

   • The efficiency is typically 90% under the condition V_IN = 12V, V_OUT = 5V, and I_OUT = 1A.
   • Optimize the design to achieve the best efficiency by selecting appropriate inductors and capacitors.

8. Dropout Voltage (V_DROPOUT):

   • The dropout voltage is typically 1.2V when V_OUT = 5V and I_OUT = 1A.
   • This parameter is important for low-voltage applications where minimizing the difference between input and output voltages is crucial.

9. Thermal Shutdown (T_SD):

   • The device will shut down if the temperature exceeds 160°C to protect against thermal damage.
   • Ensure proper heat dissipation to avoid reaching this threshold.

10. Operating Temperature (T_OP):

    • The operating temperature range is from -40°C to 125°C.
    • Design the system to operate within this range to ensure reliable performance.

11. Storage Temperature (T_STG):

    • The storage temperature range is from -65°C to 150°C.
    • Store the device in a suitable environment to prevent damage.

Layout Considerations

• Place the input and output capacitors as close as possible to the IC to minimize parasitic inductance.
• Use wide traces for the input and output paths to reduce resistance and improve thermal performance.
• Ensure that the ground plane is solid and well-connected to all components to provide a low-impedance return path.

Troubleshooting

• No Output Voltage:

  • Check the input voltage and ensure it is within the specified range.
  • Verify that the feedback resistor network is correctly connected.
  • Check for any open or short circuits in the PCB traces.

• Low Output Voltage:

  • Check the output capacitor and ensure it is the correct value and type.
  • Verify the feedback resistor values and connections.

• High Output Ripple:

  • Increase the value of the output capacitor or add a second-stage filter.
  • Ensure the inductor is the correct value and has a low DC resistance.

• Overheating:

  • Improve heat sinking by adding a heatsink or increasing the copper area on the PCB.
  • Reduce the load current if possible.