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hardwar

industrial-microsd

Also known as: Industrial microSD, pSLC microSD, High-endurance microSD, Swissbit PS-66u DP

Description

An industrial / high-endurance UHS-I microSD is the pragmatic, socketed log medium for the esp32-s3 SD-logger sidecar and for Pi 5 boot/log. Unlike consumer cards, the industrial grade uses pSLC (pseudo-SLC) or high-endurance 3D-TLC NAND, hardware ECC, dynamic wear-levelling, power-loss management and periodic data-retention refresh — the properties that matter when a node writes a continuous CSI stream for weeks and can lose power at any moment (EXP-F2 drift study).

The stored datasheet is the Swissbit PS-66u DP (pSLC, UHS-I, industrial-temp, data-protection) as a representative part; equivalent picks are ATP aMLC, SanDisk Industrial, Samsung PRO Endurance.

Capabilities

Marked from the Swissbit PS-66u DP datasheet (industrial-microsd.pdf).

Spec Value Source
Interface UHS-I (SDR104 ≤ 100 MHz), DDR50 / SDR12/25/50; SD 6.10; also SPI mode §4
Speed class Class 10 / U3 / V30 / A1 front marking
NAND pSLC (3D-TLC in pSLC mode) title / §4
Seq. write (host-limited elsewhere) 77.5–78.1 MB/s (longevity), 46.3 MB/s (high-endurance) Table 6/7
Random write 4k 1090–1660 IOPS (longevity), 800–1445 (high-endurance) Table 6/7
Endurance (64 GB, seq 128 kB) 1930 TBW (longevity) / 5871 TBW (high-endurance) Table 15/16
Data retention 10 y @ begin, 1 y @ end-of-life (40 °C) Table 14
MTBF > 3,000,000 h @ 25 °C Table 14
Operating temp −40 °C … +85 °C (industrial) Table 8
Reliability features GCC ECC, dynamic wear-levelling, power-loss management, data-retention refresh §4
Physical 15.0 × 11.0 × 0.7 mm, 0.4 g Table 13

Quirks / known issues

  • A1, not A2, on the PS-66u DP — if random-IOPS matters, spec an A2 industrial part (ATP/SanDisk Industrial) instead.
  • pSLC halves usable capacity vs raw TLC; buy the endurance you need, not the headline GB.
  • Consumer "high endurance" (dashcam) cards are cheaper but lack the −40 °C rating and power-loss management — fine for bench, not for a month-long unattended field node.
  • On the ESP32-S3 keep SD-socket CLK/CMD/D0–D3 wires short (< 5 cm) or the card falls back to default-speed and drops packets.

Used by (devices)

  • esp32-c5-s3-csi-logger — log medium in the S3 sidecar
  • esp32-c6-s3-csi-logger — log medium in the S3 sidecar
  • pi5-ax210-csi-node — boot + local CSI-dump medium
  • esp32-s3 — the SDMMC host whose ~2–4 MB/s ceiling frames the choice
  • emmc-module — soldered managed-NAND alternative for higher reliability