24V to 12V Step-Down Converter Design

katzenbastler

okProceed with the plan.

Resolve all copper-fill DRC issues:

Fix overlapping fills, wrong-net assignments, priorities, and clearances

Ensure fills respect zone segregation and intended nets

Do not change schematic intent, only PCB copper logic

Complete the BOM for manufacturing:

Replace all generic parts with real, orderable MPNs

Use conservative, industry-standard parts

Requirements:

Inductor: 8–10 µH, ≥15 A saturation

Output ceramics: 22 µF, ≥25 V, X7R

Output bulk: ≥100 µF, 25–35 V

Input bulk: ≥100 µF, ≥50 V

Passives with correct voltage, power, and temp ratings

Prefer parts that are currently in stock

Keep existing assigned MPNs unchanged for:

U1, U2, U3, Q1, D1, F1

Vendor preference:

Mouser first, Digi-Key second

After changes:

Re-run ERC and DRC

Verify manufacturability and availability

97 days

flux

1:29

Determining the appropriate action mode.

Processing plan details.

Planning PCB layout steps.

Creating a layout adjustment plan.

Accessing knowledge base.

Preparing to execute the plan.

I will resolve copper-fill DRC issues and complete the BOM with real, in‑stock MPNs while keeping U1, U2, U3, Q1, D1, and F1 unchanged.

Copper fills: set single-owner fills per layer with priority AC > 60V > 24V > GND > signals; add pour keepouts, isolation slots, and net ties; rebuild fills to clear “Layers with Multiple Fills.”
BOM: replace generics (inductor, output/input caps, comp/feedback passives) with in‑stock MPNs from Mouser, Digi‑Key fallback.
Verify: rerun ERC/DRC and availability, document changes.

Click Start to execute this plan.

Plan

#Goal

Update the PCB layout to resolve copper-fill DRC issues and complete the BOM by replacing generic components with real, in-stock parts (prioritizing Mouser with Digi-Key as a fallback), while keeping U1, U2, U3, Q1, D1, and F1 unchanged. This task ensures that net priorities, copper priorities, and clearances are correctly adjusted without altering the schematic intent.

#Implementation plan

Layout Copper-Fill Adjustments and DRC Fixes
1. Inspect and identify current DRC errors related to copper fills (e.g., 'Layers with Multiple Fills').
2. Adjust connected layers and assign a single owner net per layer with the following priority order: AC > 60V > 24V > GND > signals.
3. Add copper pour keepouts, isolation slots, and net ties where zones require segregation to prevent overlapping and wrong-net pours.
4. Rebuild and update copper fills ensuring all DRC issues are resolved.
BOM Completion with Real MPNs
1. Identify all generic components that need replacement (i.e., L1, C1..C5 for output, C6..C7 for input, C8 comp, Rfb_top/Rfb_bottom, and R1 comp resistor), ensuring U1, U2, U3, Q1, D1, and F1 remain unchanged.
2. Select and add real components with appropriate MPNs that meet the following specifications:
  1. L1: 8–10 µH, ≥15 A current rating, low DCR inductor.
  2. Output ceramics: 22 µF, ≥25 V, X7R capacitors.
  3. Output bulk: ≥100 µF, 25–35 V electrolytic or polymer caps.
  4. Input bulk: ≥100 µF, rated at ≥50 V.
  5. Small passives with correct ratings as per design requirement.
3. Prioritize picking in-stock parts from Mouser, with Digi-Key as fallback if necessary.
Verification and Final Review
1. Rerun the ERC/DRC to confirm that all copper-fill and BOM component modifications meet design rules and manufacturability criteria.
2. Document changes in net priorities and confirm the board’s manufacturability.
3. Validate that the schematic intent remains unchanged and that all modifications are fully integrated into the project.

#Success criteria

All copper-fill related DRC errors are resolved with updated net ownership and clearances.
The BOM is fully updated with real in-stock MPNs (with U1, U2, U3, Q1, D1, F1 retained) and verified against Mouser availability (with Digi-Key as a secondary check).
The final layout and BOM pass ERC/DRC checks and are ready for manufacturing.

Share DRC details

Provide power nets map

Set clearance constraints

Select inductor options

Pick capacitor MPNs

97 days

Reviews

Ground
A common return path for electric current. Commonly known as ground.
jharwinbarrozo
20.5M
Net Portal
Wirelessly connects nets on schematic. Used to organize schematics and separate functional blocks. To wirelessly connect net portals, give them same designator. #portal
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43.0M
Power Net Portal
Wirelessly connects power nets on schematic. Identical to the net portal, but with a power symbol. Used to organize schematics and separate functional blocks. To wirelessly connect power net portals, give them the same designator. #portal #power
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11.4M
Generic Resistor
A generic fixed resistor ideal for rapid circuit topology development. Its footprint automatically adapts based on the selected package case code—supporting 0402, 0603, 0805, 1203, and many other standard SMD packages, as well as axial horizontal and vertical configurations. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard resistor values: 1.0 ohm, 10 ohm, 100 ohm, 1.0k ohm, 10k ohm, 100k ohm, 1.0M ohm 1.1 ohm, 11 ohm, 110 ohm, 1.1k ohm, 11k ohm, 110k ohm, 1.1M ohm 1.2 ohm, 12 ohm, 120 ohm, 1.2k ohm, 12k ohm, 120k ohm, 1.2M ohm 1.3 ohm, 13 ohm, 130 ohm, 1.3k ohm, 13k ohm, 130k ohm, 1.3M ohm 1.5 ohm, 15 ohm, 150 ohm, 1.5k ohm, 15k ohm, 150k ohm, 1.5M ohm 1.6 ohm, 16 ohm, 160 ohm, 1.6k ohm, 16k ohm, 160k ohm, 1.6M ohm 1.8 ohm, 18 ohm, 180 ohm, 1.8K ohm, 18k ohm, 180k ohm, 1.8M ohm 2.0 ohm, 20 ohm, 200 ohm, 2.0k ohm, 20k ohm, 200k ohm, 2.0M ohm 2.2 ohm, 22 ohm, 220 ohm, 2.2k ohm, 22k ohm, 220k ohm, 2.2M ohm 2.4 ohm, 24 ohm, 240 ohm, 2.4k ohm, 24k ohm, 240k ohm, 2.4M ohm 2.7 ohm, 27 ohm, 270 ohm, 2.7k ohm, 27k ohm, 270k ohm, 2.7M ohm 3.0 ohm, 30 ohm, 300 ohm, 3.0K ohm, 30K ohm, 300K ohm, 3.0M ohm 3.3 ohm, 33 ohm, 330 ohm, 3.3k ohm, 33k ohm, 330k ohm, 3.3M ohm 3.6 ohm, 36 ohm, 360 ohm, 3.6k ohm, 36k ohm, 360k ohm, 3.6M ohm 3.9 ohm, 39 ohm, 390 ohm, 3.9k ohm, 39k ohm, 390k ohm, 3.9M ohm 4.3 ohm, 43 ohm, 430 ohm, 4.3k ohm, 43K ohm, 430K ohm, 4.3M ohm 4.7 ohm, 47 ohm, 470 ohm, 4.7k ohm, 47k ohm, 470k ohm, 4.7M ohm 5.1 ohm, 51 ohm, 510 ohm, 5.1k ohm, 51k ohm, 510k ohm, 5.1M ohm 5.6 ohm, 56 ohm, 560 ohm, 5.6k ohm, 56k ohm, 560k ohm, 5.6M ohm 6.2 ohm, 62 ohm, 620 ohm, 6.2k ohm, 62K ohm, 620K ohm, 6.2M ohm 6.8 ohm, 68 ohm, 680 ohm, 6.8k ohm, 68k ohm, 680k ohm, 6.8M ohm 7.5 ohm, 75 ohm, 750 ohm, 7.5k ohm, 75k ohm, 750k ohm, 7.5M ohm 8.2 ohm, 82 ohm, 820 ohm, 8.2k ohm, 82k ohm, 820k ohm, 8.2M ohm 9.1 ohm, 91 ohm, 910 ohm, 9.1k ohm, 91k ohm, 910k ohm, 9.1M ohm #generics #CommonPartsLibrary
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Generic Capacitor
A generic fixed capacitor ideal for rapid circuit topology development. You can choose between polarized and non-polarized types, its symbol and the footprint will automatically adapt based on your selection. Supported options include standard SMD sizes for ceramic capacitors (e.g., 0402, 0603, 0805), SMD sizes for aluminum electrolytic capacitors, and through-hole footprints for polarized capacitors. Save precious design time by seamlessly add more information to this part (value, footprint, etc.) as it becomes available. Standard capacitor values: 1.0pF, 10pF, 100pF, 1000pF, 0.01uF, 0.1uF, 1.0uF, 10uF, 100uF, 1000uF, 10000uF 1.1pF, 11pF, 110pF, 1100pF 1.2pF, 12pF, 120pF, 1200pF 1.3pF, 13pF, 130pF, 1300pF 1.5pF, 15pF, 150pF, 1500pF, 0.015uF, 0.15uF, 1.5uF, 15uF, 150uF, 1500uF 1.6pF, 16pF, 160pF, 1600pF 1.8pF, 18pF, 180pF, 1800pF 2.0pF, 20pF, 200pF, 2000pF 2.2pF, 22pF, 220pF, 2200pF, 0.022uF, 0.22uF, 2.2uF, 22uF, 220uF, 2200uF 2.4pF, 24pF, 240pF, 2400pF 2.7pF, 27pF, 270pF, 2700pF 3.0pF, 30pF, 300pF, 3000pF 3.3pF, 33pF, 330pF, 3300pF, 0.033uF, 0.33uF, 3.3uF, 33uF, 330uF, 3300uF 3.6pF, 36pF, 360pF, 3600pF 3.9pF, 39pF, 390pF, 3900pF 4.3pF, 43pF, 430pF, 4300pF 4.7pF, 47pF, 470pF, 4700pF, 0.047uF, 0.47uF, 4.7uF, 47uF, 470uF, 4700uF 5.1pF, 51pF, 510pF, 5100pF 5.6pF, 56pF, 560pF, 5600pF 6.2pF, 62pF, 620pF, 6200pF 6.8pF, 68pF, 680pF, 6800pF, 0.068uF, 0.68uF, 6.8uF, 68uF, 680uF, 6800uF 7.5pF, 75pF, 750pF, 7500pF 8.2pF, 82pF, 820pF, 8200pF 9.1pF, 91pF, 910pF, 9100pF #generics #CommonPartsLibrary
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Generic Inductor
A generic fixed inductor suitable for rapid circuit topology development. The footprint automatically adapts based on the selected package, supporting standard SMD sizes (e.g., 0402, 0603, 0805) as well as well-known inductor packages such as SDR1806, PA4320, SRN6028, and SRR1260. Standard inductor values: 1.0 nH, 10 nH, 100 nH, 1.0 µH, 10 µH, 100 µH, 1.0 mH 1.2 nH, 12 nH, 120 nH, 1.2 µH, 12 µH, 120 µH, 1.2 mH 1.5 nH, 15 nH, 150 nH, 1.5 µH, 15 µH, 150 µH, 1.5 mH 1.8 nH, 18 nH, 180 nH, 1.8 µH, 18 µH, 180 µH, 1.8 mH 2.2 nH, 22 nH, 220 nH, 2.2 µH, 22 µH, 220 µH, 2.2 mH 2.7 nH, 27 nH, 270 nH, 2.7 µH, 27 µH, 270 µH, 2.7 mH 3.3 nH, 33 nH, 330 nH, 3.3 µH, 33 µH, 330 µH, 3.3 mH 3.9 nH, 39 nH, 390 nH, 3.9 µH, 39 µH, 390 µH, 3.9 mH 4.7 nH, 47 nH, 470 nH, 4.7 µH, 47 µH, 470 µH, 4.7 mH 5.6 nH, 56 nH, 560 nH, 5.6 µH, 56 µH, 560 µH, 5.6 mH 6.8 nH, 68 nH, 680 nH, 6.8 µH, 68 µH, 680 µH, 6.8 mH 8.2 nH, 82 nH, 820 nH, 8.2 µH, 82 µH, 820 µH, 8.2 mH #generics #CommonPartsLibrary
jharwinbarrozo
15.8k
Terminal
An electrical connector acting as reusable interface to a conductor and creating a point where external circuits can be connected.
natarius
RMCF0805JT47K0
47 kOhms ±5% 0.125W, 1/8W Chip Resistor 0805 (2012 Metric) Automotive AEC-Q200 Thick Film #forLedBlink
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875105359001
10uF Capacitor Aluminum Polymer 20% 16V SMD 5x5.3mm #forLedBlink #commonpartslibrary #capacitor #aluminumpolymer #radialcan
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1.2M
CTL1206FYW1T
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Project Name

24v to 12v stepdown 100w

Description

24–30 V to 12 V / 100 W Single-Layer Synchronous Buck Converter with Robust Protection

Properties

System Architecture

Diagram

Pricing & Availability

Distributor	Qty 1
Arrow	$5.29–$8.30
Digi-Key	$5.91–$6.57
LCSC	$5.07
Mouser	$6.40
Verical	$0.53–$1.29

Controls

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katzenbastler / 24v to 12v stepdown 100w

Schematic