DETAILED SPECIFICATIONS
Input Parameters Specification
Band Mode StandardSelect either a legacy 3-Band or a precision 5-Band marking system for disc capacitors.
1st / 2nd Digit BandsDecodes the base digits representing significant numeric figures of the internal dielectric capacity.
Multiplier BandScales the base digits of the active ceramic disk capacity exponentially in Picofarads (pF).
Tolerance MarginAvailable on 5-band models. Determines allowable deviations under extreme temperatures.
Practical Operational Examples
100V 10nF Bypass Disc Cap (5-Band)
Decodes as Brown (100V), Brown (1), Black (0), Orange (x1000 multiplier), Black (±20% tolerance). Commonly used as voltage-decoupling blocks.
22pF High-Frequency Disk (3-Band)
Decodes as Red (2), Red (2), Black (x1 multiplier) with no voltage band. Designed for stability in RF resonant tanks.
Sub-Ohm Low-Pass Stabilizer
Decodes utilizing fractional digit scaling to smooth noise spikes in high-current digital signal lines.
Power Supply Damper
Utilizes high-voltage (630V) 5-Band ceramic disks to safely suppress power line grid variations and voltage peaks.
Diagrams & Theory
Radial leaded ceramic disc capacitors consist of a single disk of high-K or low-K ceramic dielectric material coated with silver contacts on both faces, encased in protective epoxy insulation.
Because their small, curved profiles make text printing difficult, manufacturers printed colored horizontal bands. Orient the capacitor disk so the band closest to the top of the body is on your left, then read from top to bottom (towards the wire leads).
Formulas & Mathematical Logic
Calculated Capacity: Capacitance (pF) = (Digit 1 + Digit 2) × Multiplier
Conversion Ratio: 1,000 pF = 1 nF | 1,000,000 pF = 1 µF
Operational Tolerances: Rmin = Value - (Value × Tolerance%) | Rmax = Value + (Value × Tolerance%)
Step-by-Step Example
Example: 5-Band Disc - Red (250V), Red (20), Black (0), Yellow (x10000), Green (±5%)
Step 1: Write down the primary voltage prefix - Red maps to 250 Volts DC.
Step 2: Read base figures - Digit 1 = 20, Digit 2 = 0. Combine them to get 20 (base value).
Step 3: Multiply by the multiplier value - 20 × 10,000 = 200,000 pF = 200 nF = 0.2 µF.
Step 4: Decode tolerance limit - Green maps to ±5% (operational scope of 190 nF to 210 nF).
How to Use This Calculator
Choose between 3-Band and 5-Band mode from the top selection dropdown trigger.
Orient your disc capacitor so that the bands read from the top towards the lead wires.
Tap each button to open the responsive iOS scrolling wheel. Select the matching band colors.
The rated capacitance, working voltage limits, and tolerances are decoded instantly.
Frequently Asked Questions
1. What does the top color band on a 5-band ceramic disc capacitor represent?
On a standard 5-band radial ceramic disc capacitor, the top color band signifies the maximum DC working voltage rating of the component (e.g. Red represents 250V, Blue represents 630V).
2. Why are 3-band disc capacitors more common in analog circuits?
Standard low-voltage logic circuits rarely require precision tolerances or high-voltage parameters. Standard 3-Band capacitors are highly cost-effective and provide stable coupling properties.
3. How can I differentiate between Class 1 and Class 2 disc materials?
Class 1 dielectrics (e.g., C0G, NP0) are temperature-compensating and have low dielectric constant properties. Class 2 dielectrics (e.g., X7R, Y5V) use high-K materials to achieve superior capacitance densities inside small disc dimensions.
4. What standard tolerance applies if my capacitor only has 3 bands?
When there are no tolerance markings, ceramic disk capacitors defaults to standard baseline manufacturing tolerance margins of ±20%.