Contact Sales & After-Sales Service

Contact & Quotation

  • Inquire: Call 0086-755-23203480, or reach out via the form below/your sales contact to discuss our design, manufacturing, and assembly capabilities.
  • Quote: Email your PCB files to Sales@pcbsync.com (Preferred for large files) or submit online. We will contact you promptly. Please ensure your email is correct.
Drag & Drop Files, Choose Files to Upload You can upload up to 3 files.

Notes:
For PCB fabrication, we require PCB design file in Gerber RS-274X format (most preferred), *.PCB/DDB (Protel, inform your program version) format or *.BRD (Eagle) format. For PCB assembly, we require PCB design file in above mentioned format, drilling file and BOM. Click to download BOM template To avoid file missing, please include all files into one folder and compress it into .zip or .rar format.

Voltage Drop Calculator - PCBsync

Voltage Drop Calculator

PCBsync Engineering Tools
PDN Analysis
Input Parameters
Supply Voltage 3.3 V
Load Current 1 A
Trace Width 0.5 mm
Trace Length 50 mm
Copper Weight 1 oz/ft²
Operating Temperature 25°C
Calculated Results
Voltage Drop
48.5
millivolts
Output: 3.251 V
Percentage Drop 1.47%
0% 3% 5% 10%
Trace Resistance
48.5 mΩ
Power Loss
48.5 mW
Current Density
57.3 A/mm²
Efficiency
98.5 %
VIN LOAD ΔV
Input 3.300 V
Drop 48.5 mV
Output 3.251 V
Voltage drop within acceptable limits (<3%)
Design Guidelines
For most digital circuits, keep voltage drop below 3% of supply voltage. Sensitive analog circuits may require <1%. Current trace carries 1A over 50mm.

Understanding PCB Voltage Drop

Every PCB trace has resistance, and when current flows through it, voltage is lost according to Ohm's Law. This voltage drop reduces the voltage available at your load, potentially causing malfunction in sensitive circuits. Proper PDN (Power Distribution Network) design ensures adequate voltage reaches all components.

Vdrop = I × R   where   R = ρ × L / A   and   ρ(T) = ρ₀ × [1 + α(T - T₀)]

Where I is current, R is trace resistance, ρ is copper resistivity (1.68×10⁻⁸ Ω·m at 20°C), L is trace length, A is cross-sectional area, and α is temperature coefficient (0.00393/°C). Resistance increases ~0.4% per degree Celsius.

Acceptable Drop Limits
  • <1% — Precision analog, RF circuits
  • <3% — Digital logic, microcontrollers
  • <5% — Power circuits, LED drivers
  • >5% — Consider wider traces or copper pours
Common Supply Voltages
  • 1.0-1.2V — Modern CPU cores (very sensitive)
  • 1.8V — DDR memory, low-power logic
  • 3.3V — Standard digital, sensors
  • 5V — Legacy logic, USB, motor drivers
Reducing Voltage Drop
  • Increase trace width (halves R)
  • Use heavier copper (2oz vs 1oz)
  • Shorten trace length where possible
  • Add parallel traces or copper pours
Temperature Effects
  • Copper resistance rises with temperature
  • At 85°C: resistance is ~25% higher than 25°C
  • Hot spots create positive feedback loops
  • Always calculate at max operating temp

Pro Tip: For power traces, consider the round-trip path. Current flows TO the load and RETURNS via ground — both paths contribute to total voltage drop. Use wide ground planes and multiple vias to minimize return path impedance.

Contact Sales & After-Sales Service

Contact & Quotation

  • Inquire: Call 0086-755-23203480, or reach out via the form below/your sales contact to discuss our design, manufacturing, and assembly capabilities.

  • Quote: Email your PCB files to Sales@pcbsync.com (Preferred for large files) or submit online. We will contact you promptly. Please ensure your email is correct.

Drag & Drop Files, Choose Files to Upload You can upload up to 3 files.

Notes:
For PCB fabrication, we require PCB design file in Gerber RS-274X format (most preferred), *.PCB/DDB (Protel, inform your program version) format or *.BRD (Eagle) format. For PCB assembly, we require PCB design file in above mentioned format, drilling file and BOM. Click to download BOM template To avoid file missing, please include all files into one folder and compress it into .zip or .rar format.