Hi There,
Please find below the schematic. I apply 3.5V at the input, but the converter doesn't seem to be boosting the output to 5V. Output is around 2.62V. Also, I have 3 22uF capacitors at the output. Please help me debug this.
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Hi There,
Please find below the schematic. I apply 3.5V at the input, but the converter doesn't seem to be boosting the output to 5V. Output is around 2.62V. Also, I have 3 22uF capacitors at the output. Please help me debug this.
Hi Prashanth:
The picture is missing for some reason. May you upload it again?
Besides, please catch the Vin, Vout, L1, L2 waveform. Thank you!
Thanks for your reply. Please find below the schematic:
Below is the image for Vin(Yellow) and Vout(Green):
Below are the images for L1 and L2:
Thank you for your help in advance.
-Prashanth
Hi Prashanth:
The Cout is too small. But I'm not sure if it's the root cause. Please add two more 22uF at output side, and ensure the Cin, Cout as close as possible to the IC.
Then do the test again and adding some waveform with t=2us/div. Thank you!
Besides, what's the load condition? Is it OK to operate without load?
Hi Minqiu,
Thanks for your reply.
On the Cout, I realized that and I have 2 more 22uF caps placed on the board on top of the existing once.The waveforms shared earlier were with these caps.
The design has a 1A/5V solenoid that will be triggered by a microcontroller. This will be the only load on the 5V rail. For testing purposes, I even tried adding 22E/5W and 15E/5W resistors. There was a small voltage dip. I will share the waveforms tomorrow.
Just for reference, I have attached the layout of that section. Please let me know if you see any issues there.
Thanks,
-Prashanth
Hi Prashanth:
"For testing purposes, I even tried adding 22E/5W and 15E/5W resistors. There was a small voltage dip. I will share the waveforms tomorrow."So the issue only happen with heavy loading?
For the layout, the input and output capacitor should be put as close as possible to IC.(WIth shortest route.)
Waiting for the zoom in waveform.
Hi Minqiu,
""For testing purposes, I even tried adding 22E/5W and 15E/5W resistors. There was a small voltage dip. I will share the waveforms tomorrow."So the issue only happen with heavy loading? "
No, the Vout is always lower than the Vin despite load.
Please find below the input(Vin) waveform (without the regulator connected)
Vin and Vout at various zooms:
Please let me know if you need any further waveforms.
Thank you.
-Prashanth
Hi Minqiu,
There was an issue with the switch and it is resolved now. Thanks for your time.
-Prashanth
Hi Prashanth:
It's glad to hear you have solved the issue. Feel free to contact us if there is any more question.