Technical note · 27 October 2026 · PXIe
PXIe selection usually follows a fixed order — instruments first, controller second, and the chassis gets whatever budget is left. That is where projects go wrong. These are the five numbers we are asked about most often, and what to check at quotation stage.
This is the specification most often skimmed and most often regretted. The dissipation a chassis can support per slot decides how much board you can install in it.
In the Gen3 platform we supply, the 18-slot PXIe-62785 is rated at 50 W per slot, while PXIe-2722G3 / 2519G3 / 2315G3 are rated at 58 W per slot. When a GPU module or a high-channel-count digitizer is on the list, that difference is the difference between running at full rate and running throttled. The Gen2 family (PXIe-2722G2, 62590, 2519G2, 2315G2) trades bandwidth for 8 GB/s system bandwidth and a 0 °C to +55 °C operating range — better suited to cabinets where ambient temperature swings.
Numbers alone do not tell you how the cooling is achieved. Our platform follows three rules throughout: rear-mounted fans delivering even airflow to every slot, industrial-grade low-ripple / low-noise power supplies, and built-in system monitoring.
Counting “total slots” is how systems end up half a card short. Four things need to be added up: total slots, hybrid slots, whether there is a dedicated system timing slot, and how many slots the controller occupies.
On the 18-slot models: PXIe-62785 provides 10 PXIe slots plus 1 timing slot and 6 hybrid slots; PXIe-2722G3 provides 17 hybrid slots. The first suits systems that are mostly PXIe with a few PXI modules alongside; the second suits mixed module populations that need flexible placement. Both controllers occupy 4 slot widths — subtract that from usable capacity before anything else.
The smaller platforms are not “cut-down” versions: 5-slot (2315G3) and 9-slot (2519G3) chassis are heavily used on benches, in portable test kits and at production stations. The 9-slot range also includes a rugged portable version with integrated display (PXIe-2519PMK, 5U outline), so field commissioning does not require a separate monitor.
High-speed digitizers, arbitrary waveform generators and multi-channel synchronous acquisition all compete for bandwidth at the same time. Gen3 system bandwidth runs from 16 GB/s (9- and 5-slot) to 24 GB/s (18-slot), with 4 GB/s or 8 GB/s per slot. Gen2 is 8 GB/s system bandwidth with 2 GB/s or 4 GB/s per slot.
The check is straightforward: sum the peak data rate of every module against system bandwidth, then confirm that the bandwidth-hungriest modules sit in the 8 GB/s slots. Doing this on the selection table is considerably cheaper than discovering it in the lab.
This is where we differ from most integrator-style suppliers: we design and build the backplane ourselves — it is not bought in and slotted into a cage.
Take the 5-slot BP-2315G3: 16 GB/s system bandwidth (PCIe Gen3 x16), 4 GB/s per slot (Gen3 x4), on-board VCXO clock, 4 hybrid slots. Below it sit an 8 GB/s Gen2 version and a PXI-Only version with PCI 32-bit and 4 PXI slots. These are not three product lines — they are variants on one hybrid backplane baseline. A PXI-Only requirement does not force a new design.
An MCU on the backplane handles real-time monitoring, and all three alarm thresholds are documented:
Supply figures are equally explicit: +3.3 V ≥ 1.38 A, +5 V ≥ 1.08 A, +12 V ≥ 1.21 A, 5 Vaux ≥ 0.81 A; continuous current capability at 50 °C ambient is 8 A per contact on J10 and 9 A per contact on J11/J12, with 3 A per contact on control-signal connectors. Smart fan control, power control and ATX supply are supported, and high-power configurations have a dedicated supply kit.
Why does this matter? When a chassis misbehaves, the first question an engineer asks is heat, fan, or power. A chassis that can separate those three answers takes minutes to diagnose; one that cannot takes days. The same backplane work, described from the VPX side, is in backplane and mechanics from one supplier.
Buying a chassis alone means controllers, modules, bus cards and power supplies come from separate suppliers — mismatched interfaces, mismatched driver revisions, and nobody owning the problem. Within one selection system, the stack below the chassis should include:
The mechanical side is our own business: 3U/4U/5U system chassis, 3U/6U/9U subracks, PXIe/CompactPCI coded guide rails, front panels and extractors, 1U–3U PDU suites, fan trays and EMC-profile cabinets — all built in our plants. Modifications happen in the same system: drilled holes, connector cut-outs, silkscreen and special colours on catalogue chassis, at low-volume MOQs.
Two plants back this up: a 6,000 m² chassis plant in Kunshan (laser cutting, CNC punching, bending, assembly) and a 23,000 m² cabinet plant in Hefei, both ISO 9001 certified (CNAS / IAF accredited). Annual capacity: 8,000 functional chassis, 200,000 standard chassis, 5,000 EMC-profile cabinets.
| Model | Total slots | Slot mix | System bandwidth | Per-slot bandwidth | Per-slot dissipation |
|---|---|---|---|---|---|
| PXIe-62785 | 18 | 10 PXIe + 1 timing + 6 hybrid | 24 GB/s | 8 GB/s | 50 W |
| PXIe-2722G3 | 18 | 17 hybrid | 24 GB/s | 8 GB/s | 58 W |
| PXIe-2519G3 | 9 | 8 hybrid | 16 GB/s | 4 GB/s | 58 W |
| PXIe-2315G3 | 5 | 4 hybrid | 16 GB/s | 4 GB/s | 58 W |
| PXIe-2519PMK | 9 | Rugged portable with display, 5U | 16 GB/s | 4 GB/s | — |
The Gen2 family (PXIe-2722G2 / 62590 / 2519G2 / 2315G2) operates from 0 °C to +55 °C with 8 GB/s system bandwidth and 2–4 GB/s per slot. The PXI platform PXI-62719A is a 19-slot 4U chassis with 132 MB/s maximum system bandwidth.
Next step. Send us your module list, slot plan and cabinet conditions. We will come back with a configuration (chassis + backplane + controller + modules); where mechanical changes or a different backplane variant are needed, our engineering team reviews both together. Request a configuration review.
Send the module list and slot plan — we will check cooling, bandwidth and slot mix before quoting.
