DESCRIPTION
The PolarStore-2N is a 3U SpaceVPX (VITA 78) payload storage module housing two high-endurance NVMe solid-state drives. Each drive connects to the host OBC via PCIe Gen3 ×4 lanes over the SpaceVPX data plane, delivering up to 3,500 MB/s sequential read per drive and sub-100 µs random-access latency. The passive architecture contains no on-board processor; the host OBC-Polar VPX manages drive access, namespacing, and data integrity via its PCIe hard block and SERDES lanes. The PolarStore-2N is suited to applications requiring deterministic low-latency access such as real-time SAR image processing buffers and science instrument data pipelines.
KEY FEATURES
- Up to 8 TB NVMe: 2× up to 4 TB high-endurance NVMe SSDs via PCIe Gen3
- 3,500 MB/s per Drive: Sequential read per drive; 7 GB/s aggregate — 6× faster than SATA variants
- <100 µs Latency: Random-read latency per drive — deterministic for real-time processing
- PCIe Gen3 ×4: 2× PCIe Gen3 ×4 lanes via SpaceVPX data plane per drive
- 700k IOPS per Drive: Random 4K read — suitable for metadata-intensive workloads
- Low Power: ∼8 W nominal — ~2× more power-efficient than comparable SATA configurations
- Passive Architecture: No on-board processor — full drive control by host OBC via PCIe
- VITA 78 Compliant: 3U SpaceVPX SLT3-PAY payload slot — compatible with all CAVU backplanes
- >20 krad TID: Radiation-tolerant drives and signal conditioning — latch-up immune
- OBC-Polar VPX Ready: Pre-validated with NVMe over SERDES firmware personality
- Conduction-Cooled: VITA 48.2 wedge-lock — sealed, vacuum-compatible
- Compact Mass: ∼195 g — up to 8 TB in a single 3U payload slot
DRIVE SPECIFICATIONS
- Drive count: 2 (fixed)
- Drive type: High-endurance NVMe SSD with PCIe Gen3 ×4 interface, industrial temperature range
- Capacity per drive: Up to 4 TB
- Total raw capacity: Up to 8 TB
- Protocol: NVMe 1.4 over PCIe Gen3 ×4
- Sequential read: Up to 3,500 MB/s per drive (~7 GB/s aggregate)
- Sequential write: Up to 3,000 MB/s per drive
- Random read (4K): Up to 700,000 IOPS per drive
- Random write (4K): Up to 250,000 IOPS per drive
- Read latency: <100 µs (random, 4K)
- Endurance: >1 DWPD, rated for a 5-year mission lifetime
HOST INTERFACE & POWER
- Host interface: NVMe (PCIe Gen3 ×4 per drive) via SpaceVPX data plane SERDES
- On-card logic: Passive design with no processor, controller, or firmware
- PCIe lanes used: 8 total lanes (4 per drive) via SpaceVPX data plane
- Power supply: 5 V and 12 V provided from SpaceVPX backplane P0/J0
- Power (nominal): ~8 W with both drives active
- Power (idle): ~3 W with drives in low-power state
RADIATION & ENVIRONMENT
- TID tolerance: >20 krad (Si) for drives and signal path
- SEL immunity: Latch-up immune signal conditioning
- Operating temperature: −40°C to +85°C (conduction-cooled, VITA 48.2)
- Non-operating temperature: −55°C to +125°C
- Shock: Compliant with MIL-STD-810 Method 516
- Vibration: Compliant with MIL-STD-810 Method 514
- Vacuum: Fully compatible with no convection cooling paths
MECHANICAL
- Form factor: 3U SpaceVPX (VITA 78) payload module
- Slot profile: SLT3-PAY
- Dimensions: 100 × 160 mm (220 mm depth option available)
- Connector: VITA-46 MULTIGIG RT2
- Cooling: Conduction-cooled with VITA 48.2 wedge-lock
- Mass: ~195 g
SYSTEM COMPATIBILITY
- OBC-Polar VPX: Native support with NVMe recorder personality pre-validated
- SpaceVPX-BP-SS: Compatible with any SLT3-PAY slot (uses 8 PCIe lanes)
- SpaceVPX-BP-DS: Compatible with any SLT3-PAY slot, supports dual-string configurations
- PCIe switch card: Enables fan-out to multiple PolarStore-2N modules via PCIe switch payload module
- PolarStore-2S: Can co-reside on the same backplane for mixed SATA / NVMe configurations
