The Gap Between Ideal and Real Components
Auto Match synthesis gives ideal component values (e.g., L = 3.54 nH, C = 6.82 pF) that may not exist in standard SMD catalog values. Real components also have finite Q, self-resonant frequency, and package parasitics. Substitution involves finding the closest standard value and verifying the design still meets spec.
Standard SMD Inductor Series (E12 for RF)
E12 series inductance values (nH): 1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2 (then × 10: 10, 12, 15, 18, 22, 27, 33, 39, 47, 56, 68, 82, 100 nH) Ideal value: 3.54 nH → nearest standard: 3.3 nH or 3.9 nH Try both: simulate which gives better S11 at target frequency
Standard SMD Capacitor Series (C0G/NP0)
E12 series capacitance values (pF): 1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2 Standard larger values: 10, 12, 15, 18, 22, 27, 33, 39, 47 pF Ideal value: 6.82 pF → nearest standard: 6.8 pF ✓ (exact E12 value) Alternative: 8.2 pF (over-compensates) or 5.6 pF (under-compensates)
Using RF View Real Match
- Complete Auto Match → note ideal L and C values
- Tap "Real Match" → RF View automatically:
- Searches Murata catalog for nearest L value in 0402 LQP series
- Searches for nearest C value in 0402 C0G GRM series
- Loads each component's measured S2P file (includes Q, SRF, parasitics)
- Re-simulates complete circuit with real component data
- Compare real vs ideal S11: see performance impact of component substitution
- If S11 degrades: try ±1 step in component value using the +/− adjustment
Manual Substitution Workflow (Without RF View Real Match)
Step 1: List ideal values: L=3.54nH, C=6.82pF Step 2: Find nearest E12 values: L→3.3nH, C→6.8pF Step 3: Download .s2p for each from SimSurfing.com Step 4: Load each as S2P block in RF View Circuit Simulator Step 5: Simulate → verify S11 still <−10dB Step 6: If not: try 3.9nH for L → re-simulate
RF View Real Match: One tap substitutes ideal L/C with nearest Murata catalog components and re-simulates with real component measured data. Saves hours of manual component selection. Free on Android.