The Keysight U4203A is a 34-channel flying lead probe set for high-speed digital system testing and debugging. It connects directly to Keysight’s 16850-series portable logic analyzers and U4154A/U4164A AXIe-based logic analysis modules via a 160-pin interface. The probe set comprises 32 data channels and 2 clock channels, supporting both differential and single-ended clock probing alongside single-ended data acquisition. Flying leads provide flexible signal access across PC board components up to 1.5 Gb/s typical operation, with maximum recommended state data rates to 4 Gb/s.
Technical Specifications
• Channel Count: 34 channels (32 data + 2 clock)
• Probe Type: Flying lead, single-ended
• Interface: 160-pin direct connect
• Maximum Data Rate: 1.5 Gb/s typical; 4 Gb/s maximum recommended state data rate
• Minimum Signal Amplitude: 200 mV (Vmax-Vmin); 300 mV required for data rates exceeding 2.5 Gb/s
• Input Capacitance: < 0.7 pF to 0.9 pF
• Resistive Signal Pin: 130 Ω
• Clock Input: Differential or single-ended supported
• Weight: 0.69 kg
– Key Features
• Direct-connect 160-pin interface eliminates adapter requirements
• Configurable for channel expansion—stack up to four probes for 136 total channels
• Low input capacitance minimizes probe loading and signal distortion
• Compatible accessory ecosystem supports diverse board topologies and component packages
– Typical Applications
• High-speed digital system debugging and validation
• Multi-point signal acquisition from embedded systems and digital boards
• Protocol analysis and timing verification at data rates to 4 Gb/s
– Compatibility & Integration
Works with Keysight 16850-series portable logic analyzers (16851A through 16854A) and U4154A/B and U4164A AXIe-based logic analysis modules. Supports scalable probe configurations: one probe yields 34 channels; two probes provide 68 channels; three yield 102 channels; four yield 136 channels. Optional full accessory kit (part number U4203-68702) supplies signal access hardware for various component types.















