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TPS61021ADSGR Underperforming? Here’s What Could Be Wrong

TPS61021ADSGR Underperforming? Here’s What Could Be Wrong

If you're experiencing issues with the TPS61021ADSGR, which is a boost converter IC typically used in Power supply circuits, and it seems to be underperforming, several factors could be contributing to this issue. Let’s break down the potential causes and provide a clear, step-by-step solution for troubleshooting and fixing the problem.

1. Input Voltage Problems

The TPS61021ADSGR requires a stable input voltage to operate properly. If the input voltage is too low, the boost converter may not be able to output the expected voltage.

Possible Cause:

Input voltage might be below the recommended range for the device.

Solution:

Check the input voltage using a multimeter. The TPS61021ADSGR typically operates with input voltages between 0.8V and 3.6V. Ensure that your input is within this range. If the input voltage is too low, you might need to use a higher voltage power source. 2. Incorrect Feedback Loop or capacitor Issues

The feedback loop in the boost converter is crucial for maintaining stable output voltage. If there’s an issue with the feedback resistor network or capacitors, the output voltage can fluctuate or be lower than expected.

Possible Cause:

Incorrect feedback resistor values or faulty capacitors.

Solution:

Verify the resistor values in the feedback loop are correctly placed as per the application note or datasheet. Inspect the capacitors (especially the ones around the feedback pin). Faulty or low-quality capacitors can lead to instability. Ensure the capacitors are within the recommended range of values as per the datasheet for stable performance. 3. Output Voltage Set Incorrectly

The TPS61021ADSGR allows you to set the desired output voltage using external components. If these components are improperly chosen or configured, the output voltage might be incorrect.

Possible Cause:

Incorrect output voltage settings.

Solution:

Double-check the resistors used for setting the output voltage. According to the datasheet, the output voltage is determined by the ratio of two resistors. Ensure they are correctly selected to achieve your desired output. If you’ve used a custom setup, refer to the application circuits in the datasheet to ensure proper resistor values and configurations. 4. Excessive Load on Output

If the output is underperforming, the issue could also be a result of drawing too much current from the converter.

Possible Cause:

The load may be higher than the converter’s maximum current rating.

Solution:

Check the current demand of the circuit connected to the output. The TPS61021ADSGR can deliver up to 1.8A at lower voltages, but you must ensure that the load does not exceed this limit. Reduce the load current if necessary, or choose a different power supply that can provide the necessary current. 5. PCB Layout Issues

Improper PCB layout can negatively impact the performance of any switching regulator, including the TPS61021ADSGR. Poor layout can lead to noise, instability, or inefficient power conversion.

Possible Cause:

Poor PCB layout or ground plane issues.

Solution:

Review the PCB layout for the TPS61021ADSGR, especially the placement of the inductor, capacitors, and the feedback network. Ensure that high-current traces are thick enough to handle the load and that the ground plane is solid and continuous. Minimize the length of traces between the IC and the components to reduce noise and losses. 6. Thermal Overload or Poor Heat Dissipation

Power converters generate heat, and excessive heat can lead to thermal shutdown or underperformance.

Possible Cause:

The IC might be overheating, leading to thermal shutdown or reduced efficiency.

Solution:

Ensure proper heat dissipation for the TPS61021ADSGR. If necessary, add a heatsink or improve airflow around the IC. Check the IC's temperature to see if it’s within the recommended operating range (it should not exceed 125°C). If the converter is running too hot, you might need to decrease the load or improve cooling in the system. 7. Faulty Components

Sometimes, the issue might be as simple as a faulty component, such as a bad inductor, capacitor, or even the IC itself.

Possible Cause:

Defective inductor, capacitor, or the IC might be damaged.

Solution:

Inspect all the components in the boost converter circuit. Use a multimeter to test passive components like capacitors and resistors for faults. Replace any damaged components, particularly the inductor and capacitors that are critical for stable operation.

Summary of Solutions:

Check the Input Voltage: Ensure it’s within the recommended range (0.8V to 3.6V). Verify Feedback Loop Components: Ensure resistors and capacitors in the feedback loop are correct and functioning. Adjust Output Voltage: Double-check the resistors for the desired output voltage. Manage Load Current: Ensure the load does not exceed the converter's current rating (1.8A). Review PCB Layout: Ensure a good layout with proper ground planes and trace thickness. Improve Thermal Management : Ensure proper heat dissipation to avoid overheating. Inspect Components: Check for defective components and replace them as necessary.

By following these steps, you should be able to diagnose and resolve most performance issues with the TPS61021ADSGR boost converter. If problems persist, it might be a good idea to replace the IC or consult the manufacturer for further assistance.