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Edit #1! Feedback has been incorporated, original design bodged:

Before I re-design the board to fix the errors, do these results point to additional problems with the design?

Edit #2! Design review of second revision:

Per the feedback from Jonathan S. and bobflux, I've come up with a second revision of this board and hope to submit it for more feedback prior to getting it manufactured.

In summary, the changes are as follows:

  • Removed large test points that sliced up the output pour.
  • Added a larger output diode that can handle more current.
  • Added a copper pour below the output diode to remove heat.
  • Generally tightened output layout.
  • Add larger ground plane below the boost converter.
  • C10 is now 1uF.
  • C11 is a much lower ESR 56uF cap, 25SVPF56M.

Here's the schematic:

Revision 2 Schematic

Here's the complete layout, followed by the front and back copper layers:

Revision 2 Layout Complete

Revision 2 Layout F Copper

Revision 2 Layout B Copper

I'll ask below for feedback, integrate it and then keep posting along with my progress.

Edit! Feedback has been incorporated:

Before I re-design the board to fix the errors, do these results point to additional problems with the design?

Edit #1! Feedback has been incorporated, original design bodged:

Before I re-design the board to fix the errors, do these results point to additional problems with the design?

Edit #2! Design review of second revision:

Per the feedback from Jonathan S. and bobflux, I've come up with a second revision of this board and hope to submit it for more feedback prior to getting it manufactured.

In summary, the changes are as follows:

  • Removed large test points that sliced up the output pour.
  • Added a larger output diode that can handle more current.
  • Added a copper pour below the output diode to remove heat.
  • Generally tightened output layout.
  • Add larger ground plane below the boost converter.
  • C10 is now 1uF.
  • C11 is a much lower ESR 56uF cap, 25SVPF56M.

Here's the schematic:

Revision 2 Schematic

Here's the complete layout, followed by the front and back copper layers:

Revision 2 Layout Complete

Revision 2 Layout F Copper

Revision 2 Layout B Copper

I'll ask below for feedback, integrate it and then keep posting along with my progress.

Per feedback, I've installed new components in the circuit and repeated the experiments.
Source Link

I'm trying to implement a boost converter using TI's TPS55340.

After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input voltage: 11-13 V
  • Output Voltage: 16 V @ ~3 A (WEBENCH set to 2.91 A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the boost converter is realized:

enter image description here

The input 12 V is input to the board less than 3 cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16 V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the boost converter:

Using my benchtop power supply set to 12 V, and my DC load configured to draw 0.1 A, 0.5 A and 1 A, I measured the output using my oscilloscope and took screenshots. In each figure the 12 V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1 A:

0.1A

0.5 A:

0.5A

1 A:

1A

The Vpp of the output being all the way up near 3 V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode. I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

Edit! Feedback has been incorporated:

The replacement parts have arrived and I've installed them on the PCB.

C11 is again 56uF but now has a much lower ESR. It's PN is 25SVPF56M.

C10 is now 1uF (up from 2.2nF). It's PN is
C1206C105K3RAC7800
.

Here are the results. Same setup as last time, input power set to 12V, DC electronic load providing the load. This time we're only probing the output of the circuit.

0.1A:

0.1A, improved design

0.5A:

0.5A, improved design

1A:

1A, improved design

Here is the modified board (& probing setup):

Modified Circuit

The results here are mixed. At low current, the results are greatly improved. However, up at 1A there is still 2V of ripple on the output vs. the expected value of ~50mV.

This is likely due to the incorrect layout as pointed out by commenters.

Before I re-design the board to fix the errors, do these results point to additional problems with the design?

I'm trying to implement a boost converter using TI's TPS55340.

After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input voltage: 11-13 V
  • Output Voltage: 16 V @ ~3 A (WEBENCH set to 2.91 A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the boost converter is realized:

enter image description here

The input 12 V is input to the board less than 3 cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16 V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the boost converter:

Using my benchtop power supply set to 12 V, and my DC load configured to draw 0.1 A, 0.5 A and 1 A, I measured the output using my oscilloscope and took screenshots. In each figure the 12 V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1 A:

0.1A

0.5 A:

0.5A

1 A:

1A

The Vpp of the output being all the way up near 3 V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode. I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

I'm trying to implement a boost converter using TI's TPS55340.

After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input voltage: 11-13 V
  • Output Voltage: 16 V @ ~3 A (WEBENCH set to 2.91 A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the boost converter is realized:

enter image description here

The input 12 V is input to the board less than 3 cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16 V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the boost converter:

Using my benchtop power supply set to 12 V, and my DC load configured to draw 0.1 A, 0.5 A and 1 A, I measured the output using my oscilloscope and took screenshots. In each figure the 12 V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1 A:

0.1A

0.5 A:

0.5A

1 A:

1A

The Vpp of the output being all the way up near 3 V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode. I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

Edit! Feedback has been incorporated:

The replacement parts have arrived and I've installed them on the PCB.

C11 is again 56uF but now has a much lower ESR. It's PN is 25SVPF56M.

C10 is now 1uF (up from 2.2nF). It's PN is
C1206C105K3RAC7800
.

Here are the results. Same setup as last time, input power set to 12V, DC electronic load providing the load. This time we're only probing the output of the circuit.

0.1A:

0.1A, improved design

0.5A:

0.5A, improved design

1A:

1A, improved design

Here is the modified board (& probing setup):

Modified Circuit

The results here are mixed. At low current, the results are greatly improved. However, up at 1A there is still 2V of ripple on the output vs. the expected value of ~50mV.

This is likely due to the incorrect layout as pointed out by commenters.

Before I re-design the board to fix the errors, do these results point to additional problems with the design?

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Lots of Electrical Noiseelectrical noise at Boost Converter Outputboost converter output

I'm trying to implement a boost converter using TI's TPS55340. 

After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input Voltagevoltage: 11V11-13V13 V
  • Output Voltage: 16V16 V @ ~3A~3 A (WEBENCH set to 2.91A91 A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the Boost Converterboost converter is realized:

enter image description here

The input 12V12 V is input to the board less than 3cm3 cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16V16 V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the Boost Converterboost converter:

Using my benchtop power supply set to 12V12 V, and my DC load configured to draw 0.1A1 A, 0.5A5 A and 1A1 A, I measured the output using my oscilloscope and took screenshots. In each figure the 12V12 V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1A1 A:

0.1A

0.5A5 A:

0.5A

1A1 A:

1A

The Vpp of the output being all the way up near 3V3 V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode?. I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

Lots of Electrical Noise at Boost Converter Output

I'm trying to implement a boost converter using TI's TPS55340. After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input Voltage: 11V-13V
  • Output Voltage: 16V @ ~3A (WEBENCH set to 2.91A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the Boost Converter is realized:

enter image description here

The input 12V is input to the board less than 3cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the Boost Converter:

Using my benchtop power supply set to 12V, and my DC load configured to draw 0.1A, 0.5A and 1A, I measured the output using my oscilloscope and took screenshots. In each figure the 12V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1A:

0.1A

0.5A:

0.5A

1A:

1A

The Vpp of the output being all the way up near 3V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode? I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

Lots of electrical noise at boost converter output

I'm trying to implement a boost converter using TI's TPS55340. 

After spinning up the design, I have found that the output ripple is almost 8x what I expected to see given my design parameters. First, let's get into the design, schematic and layout.

In short, my design parameters:

  • Input voltage: 11-13 V
  • Output Voltage: 16 V @ ~3 A (WEBENCH set to 2.91 A)

Plugging this into WEBENCH resulted in the following implementation (link to HTML):

Schematic

Layout

I translated this into KiCAD as follows:

enter image description here

And here's the region of my PCB where the boost converter is realized:

enter image description here

The input 12 V is input to the board less than 3 cm away via a DC barrel jack.

There is a mistake in the layout, I should not have sliced through the 16 V output plane with the V_SW test point, but I have fixed this with a few bodge wires. Here is a photo of the assembled region of the circuit:

enter image description here

You'll likely be interested in the critical components to implement the boost converter:

Using my benchtop power supply set to 12 V, and my DC load configured to draw 0.1 A, 0.5 A and 1 A, I measured the output using my oscilloscope and took screenshots. In each figure the 12 V input is the blue trace and the output is the yellow. Both channels are in AC coupling mode, and neither probe is using the ground alligator clip -- both are using the ring-tip ground spring.

0.1 A:

0.1A

0.5 A:

0.5A

1 A:

1A

The Vpp of the output being all the way up near 3 V is way out of spec for the design, according to the WEBENCH model it should be less than 57.5 mV.

I think the problem stems from a weak output diode. I notice that the part gets pretty hot during operation. What do you think?

If there is anything missing you'd like to see from the design, let me know.

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