1. What is SMD Resistance Code?

Definition: SMD (Surface Mount Device) resistors use a coding system to indicate their resistance value due to their small size.

Purpose: This calculator helps decode the numerical or alphanumeric markings on SMD resistors to determine their resistance value in ohms.

2. How Does the Calculator Work?

The calculator interprets different SMD coding formats:

• 3-digit code: First two digits are significant figures, third digit is multiplier (e.g., "103" = 10 × 10³ = 10kΩ)
• 4-digit code: First three digits are significant figures, fourth digit is multiplier (e.g., "1002" = 100 × 10² = 10kΩ)
• R notation: "R" acts as a decimal point (e.g., "4R7" = 4.7Ω, "R047" = 0.047Ω)

3. Importance of SMD Resistance Codes

Details: Correct interpretation is crucial for circuit design, repair, and component replacement in modern electronics.

4. Using the Calculator

Tips: Enter the SMD code exactly as it appears on the resistor. The calculator will automatically detect the format and calculate the resistance.

5. Frequently Asked Questions (FAQ)

Q1: What if my resistor has letters in the code?
A: Some SMD resistors use EIA-96 codes with numbers and letters. This calculator handles basic numerical codes only.

Q2: How accurate are these codes?
A: The code indicates nominal value. Actual resistance depends on tolerance (typically ±1% to ±5%).

Q3: What about very small resistors (0402 size)?
A: Some tiny resistors may have no marking at all. You'll need to measure them with a multimeter.

Q4: How do I know if it's ohms, kilohms, or megohms?
A: The calculator returns the value in ohms. Divide by 1000 for kilohms, by 1,000,000 for megohms.

Q5: What does "0" or "000" mean?
A: "0" means 0Ω (jumper), "000" means 0Ω with higher current rating.