II. Model Interpretation

PXI: Standard PXI bus, compatible with PXIe mixed slot positions.

2575: NI's high-density multiplexer series code, representing a 196×1 single-wire or 95/98×1 dual-wire multiplexer NI.

Full name: PXI-2575 196-channel 1-Wire PXI multiplexer switch module.

Topology identifier: NISWITCH_TOPOLOGY_2575_196×1 (single-wire), NISWITCH_TOPOLOGY_2575_95×1 (dual-wire), NISWITCH_TOPOLOGY_2575_98×1 (dual-wire), the hardware-fixed topology NI.

III. Technical Parameters

(1) Switch and Electrical Characteristics

Topology: 1-Wire 196×1 multiplexer; 2-Wire 95×1 or 98×1 multiplexer (total 99 DPDT latch relays) NI.

Relay type: Electromechanical latch relays, gold-plated palladium-ruthenium alloy contacts, pulse-driven (only switching power consumption) NI.

Maximum switching voltage: 100 VDC / 100 Vrms (CAT I), pulse withstand voltage 500 V NI.

Single-channel maximum switching/carrying current: 1 A (resistive load) NI.

Maximum switching power: DC 60 W, AC 62.5 VA (DC~60 Hz).

On-resistance: Typical value < 100 mΩ.

Thermal offset: Maximum 12 µV NI.

Operating bandwidth: Single-wire > 20 MHz, dual-wire > 8 MHz (–3 dB, 50 Ω) NI.

Action time: Typical 2 ms, maximum 4 ms.

Channel isolation: 10 kHz > 90 dB; 100 kHz > 70 dB; 1 MHz > 50 dB (slightly lower for relay channels) NI.

(2) Life and Scan Parameters

Mechanical life: 2×10⁷ on-off cycles NI.

Full-load electrical life: 1×10⁵ on-off cycles NI.

Scan list: Maximum 32,000 programmable scan sequences.

Full-channel scan rate: Maximum 140 times/second NI.

(3) Trigger and Control

Trigger channels: Support PXI backplane Trigger 0~Trigger 7 hardware bus NI.

Minimum trigger pulse width: 150 ns (when digital filtering is disabled) NI.

Built-in functions: Each relay has an independent counter, and the locked state is maintained when the power is off NI.

(4) Physical and Environmental Parameters

Form specification: Standard 3U PXI single-slot module.

Front-end connector: 200-pin LFH matrix male connector NI.

Form size: 216 mm × 20 mm × 130 mm.

Weight: Approximately 0.23 kg.

Power supply: PXI backplane 5 V/3.3 V; typical power consumption 6 W (5 V) + 2.5 W (3.3 V); latch stable zero power consumption NI.

Operating temperature: 0 ℃ ~ 55 ℃.

Storage temperature: –20 ℃ ~ 70 ℃.

Relative humidity: 5% ~ 85%, no condensation.

IV. Interface and Topology Configuration

Front-end I/O Interface

All signals are led out through the 200-pin LFH matrix male connector, including:

Single-wire mode: 196 input channels + 1 common output;

Dual-wire mode: 95/98 differential input channels + 1 differential common output;

The remaining pins are shielding ground and reference ground, with electrical isolation between channels NI.

Bus and software communication Bus Interface: Standard PXI backplane, compatible with PXIe mixed slots, automatically acquires power, clock, and trigger NI.

Driver: Standard NI- SWITCH, compliant with IVI specification NI.

Software Support: LabVIEW, TestStand, LabWindows/CVI, Python, etc., from NI.

Basic Functions: NI MAX can perform hardware recognition, channel status reading, scan editing, trigger configuration, and life count query NI.

Synchronization Capability: PXI trigger bus enables multi-module high-precision synchronous switching NI.

VII. Core Functions

Ultra-high Density Multiplexing: Single slot 196 single-line or 95/98 dual-line, a single module replaces multiple low-channel-count switches, saving slots and costs NI.

Latching Low Power Consumption: Only power consumption during switching, zero power consumption in steady state, suitable for long-term operation, battery-powered systems NI.

Medium and High Frequency Signal Routing: Single-line 20 MHz, dual-line 8 MHz bandwidth, suitable for medium and high-frequency analog and digital signal switching NI.

High-Speed Hardware Scan: 32,000-step scan list, executed by hardware automatically, improving high-channel-count test throughput NI.

Hardware Synchronous Trigger: PXI backplane trigger, precise timing, meeting requirements for multi-instrument collaboration and parallel testing NI.

Relay Life Monitoring: On-board counter records on/off times, supports predictive maintenance, reducing downtime NI.

Power Failure State Retention: Locks relay power-off to maintain channel status, no need for reconfiguration upon restart, enhancing system stability NI.

VI. Application Scenarios

Semiconductor Testing: Multi-pin signal multiplexing for wafers/chips, high-channel-count automated testing system NI.

Automotive Electronics: Wire harness testing, ECU multi-channel signal switching, sensor signal inspection NI.

Industrial Data Acquisition: Multi-channel selection for large-scale sensors (voltage/current/resistance) signals, centralized acquisition NI.

ATE Equipment: High-channel-count function testing, aging testing, signal routing matrix NI.

Laboratory Research: Multi-channel signal comparison testing, loop switching, verification of medium and high-frequency signal routing NI.

Low-Power Monitoring System: Utilizes latch characteristics, suitable for long-term operation with extremely low energy consumption NI.

VIII. Usage and Maintenance Instructions

Usage Points

Installation: Insert into 3U standard slot, tighten panel screws, keep away from strong vibration / strong electromagnetic interference; PXIe chassis prefer mixed slots NI.

Cabling: Match 200-pin LFH cable, gently insert and remove; use shielded cables for high-frequency / precise signals and reliably ground NI.

Electrical Limits: Strictly follow 100 V/1 A rated parameters; connect shunt diodes for inductive loads to prevent reverse high voltage from damaging contacts NI.

Trigger Mode: Use software for debugging; use PXI hardware for high-speed / multi-module synchronization NI.

Power On Specification: Connect cables first, then power on; disconnect signal cables after power off, do not plug or unplug while powered on NI.

Maintenance Instructions

Regular Inspection: Inspect 200-pin LFH connector quarterly, clean dust, and check for loose oxidation NI.

Life Management: Regularly read on/off times, plan to replace relays in advance when the load condition approaches 1×10⁵ times (supports on-site single-channel replacement) NI.

Environmental Control: Maintain dry and ventilated conditions, temperature 0~55 ℃, avoid condensation and dust accumulation NI.

Fault Handling: Check wiring, grounding, and trigger configuration first for channel abnormalities; replace single-channel relay on-site NI.

Storage Requirements: Disconnect cables when not in use, protect interface from dust, store in a dry environment at -20~70 ℃ NI.

Calibration: Suggest annual calibration, test on/off status, conductance resistance, bandwidth, and latch retention performance NI.