• State Resolved
  • Locked Locked
  • Replies 4 replies
  • Subscribers 62 subscribers
  • Views 319 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

LM43601: Inverting configuration not regulating above 150mA

Jeremy Kent
Prodigy 50 points
Part Number: LM43601

Requirements +5Vin, -15Vout @ 0.3A

Circuit designed from Webench using these specs. When prototyped, it does not regulate well above 150mA. Even at this modest load, inductor gets hot but -15V is present. Above 150mA, regulation is lost and droops to around -8V. Also this regulator would not start up into a very light load (20mA) without a 22n capacitor connected to the SS pin.

  • 0
    TI__Genius 11040 points
    Hello,

    Thank you for sharing the schematic for your design.

    Would you be able to help share additional information about this design?

    1. Can you share the inductor part number?
    2. Can you share the PCB layout?
    3. Do you have an oscilloscope waveform of VIN, SW, VOUT when the output voltage drops to -8V above 150mA and one waveform when the device is regulated at -15?

    Thank you,
    Katelyn
  • 0 in reply to Katelyn Wiggenhorn
    TI__Genius 11040 points
    Hello,

    I want to follow up with you. Would you be able to share additional information about this design?

    1. Can you share the inductor part number?
    2. Can you share the PCB layout?
    3. Do you have an oscilloscope waveform of VIN, SW, VOUT when the output voltage drops to -8V above 150mA and one waveform when the device is regulated at -15?

    Thank you,
    Katelyn
  • 0 in reply to Katelyn Wiggenhorn
    TI__Genius 11040 points
    Hello,

    I want to follow up with you. Are you still seeing this issue? If so, could you help share additional information about this design?

    1. Can you share the inductor part number?
    2. Can you share the PCB layout?
    3. Do you have an oscilloscope waveform of VIN, SW, VOUT when the output voltage drops to -8V above 150mA and one waveform when the device is regulated at -15?

    Thank you,
    Katelyn
  • 0 in reply to Katelyn Wiggenhorn
    TI__Genius 11040 points
    Hello,

    Due to inactivity, I am going to close this thread. Please feel free to respond to this thread if you have any additional questions.

    Best Regards,
    Katelyn