The Keysight E4991B Impedance Analyzer characterizes electronic components, semiconductor devices, and materials across 1 MHz to 3 GHz with ±0.65% basic accuracy. This RF-IV method instrument measures impedance, admittance, reflection coefficient, and equivalent circuit parameters including R, X, L, C, Q, and D. The 10.4-inch color LCD touch screen display supports real-time parameter visualization. DC bias capability (Option 001) provides 0 V to ±40 V voltage and 0 A to ±100 mA current sourcing with 1 mV and 2 μA resolution respectively. Test signal levels span 4.47 mVrms to 502 mVrms (AC voltage), 89.4 μArms to 10 mArms (AC current), and −40 dBm to +1 dBm (power).
Technical Specifications
• Frequency Range: 1 MHz to 3 GHz (upgradable options: 500 MHz, 1 GHz)
• Impedance Measurement Range (10% accuracy): 120 mΩ to 52 kΩ
• Basic Accuracy: ±0.65%
• Measurement Parameters: |Z|, |Y|, θ, R, X, G, B, L, C, D, Q, |Γ|, Γx, Γy, θΓ, Vac, Iac, Vdc1, Idc1
• Measurement Method: RF-IV
• External Reference Input: 10 MHz ± 10 ppm, 0 dBm ± 3 dB, 50 Ω nominal, BNC female connector
• Internal Reference Output: 10 MHz ± 10 ppm, 0 dBm ± 3 dB into 50 Ω, 50 Ω nominal, BNC female connector
– Key Features
• Dielectric material measurement (Option 002): direct permittivity and permeability readout including |εr|, εr’, εr”, tanδ(ε), |μr|, μr’, μr”, tanδ(μ)
• Temperature dependency analysis (Option 007)
• On-wafer and micro-component measurement via probe station kit (Option 010) with guaranteed specifications at 7 mm test head port
• Equivalent circuit simulation and comparison
• Pass/fail limit line testing
• Compact form factor with minimal footprint
– Typical Applications
• Passive component characterization: capacitors, inductors, ferrite beads
• Material property evaluation and temperature coefficient analysis
• On-wafer device impedance measurement up to 3 GHz
• Production and quality assurance testing
– Compatibility & Integration
• Dielectric material test fixture: 16453A
• Magnetic material test fixture: 16454A
• N1500A-005 materials measurement suite (up to 1 GHz)
• 7 mm connector compatibility with legacy accessories


















