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AT25DF321A-SH-T

Dialog Semiconductor Adesto Adesto Technologies · NOR FLASH · SOIC-8-208mil

AT25DF321A-SH-T from Dialog Semiconductor Adesto Adesto Technologies, in a SOIC-8-208mil. Pinout and pin descriptions extracted from the manufacturer datasheet by ds2sf; symbol, footprint, and 3D from KiCad-official CAD.

Pinout

Pin Name Type Function
1 CS input Chip Select (active low). A high-to-low transition starts an SPI operation; a low-to-high transition ends it. When deasserted, SO is high-impedance and SI data is ignored; the device enters standby (not Deep Power-Down).
2 SO/SOI bidirectional Serial Output; data is clocked out on the falling edge of SCK. Becomes an input (SOI) during Dual-Input Byte/Page Program to accept two bits per SCK rising edge with SI. High-impedance whenever CS is deasserted.
3 WP input Write Protect (active low). Controls hardware locking of protected sectors. Internally pulled high, so it may be left floating if hardware protection is unused, but tying it to VCC is recommended.
4 GND power_in Ground reference for the device supply. Connect to the system ground.
5 SI/SIO bidirectional Serial Input; command, address, and data bits are latched on the rising edge of SCK. Becomes an output (SIO) during Dual-Output Read Array, producing two bits per SCK falling edge with SO. Ignored whenever CS is deasserted.
6 SCK input Serial Clock input. Controls data flow to/from the device: SI is latched on the rising edge, SO is clocked out on the falling edge. Supports SPI Modes 0 and 3 up to 85 MHz (100 MHz in RapidS mode).
7 HOLD input Hold (active low). Pauses serial communication without deselecting or resetting the device; while asserted, SCK transitions and SI data are ignored and SO is high-impedance. Internally pulled high; tie to VCC if unused.
8 VCC power_in Device power supply, 2.7 V to 3.6 V. Powers read, program, and erase operations; no separate programming voltage is required.

Key specifications

Parameter Value
Manufacturer Dialog Semiconductor Adesto Adesto Technologies
Package SOIC-8-208mil
Category Memory
Pins 8

Ordering variants

  • AT25DF321A-SH-TSH-B
  • AT25DF321A-SH-T
  • AT25DF321A-SH-TMH-Y
  • AT25DF321A-SH-TMH-T

CAD (KiCad official)

  • Symbol: AT25DF321A-SH-T
  • Footprint: Package_SO:SOIC-8_3.9x4.9mm_P1.27mm
  • 3D model: SOIC-8-208mil (KiCad packages3D, STEP)

Provenance

Data extracted from the manufacturer datasheet, not a distributor listing:

  • Datasheet: Dialog Semiconductor Adesto Adesto Technologies datasheet (None pp, sha256 c4bb2e270a1cba72, retrieved 2026-08-17, tier: lcsc)
  • Extractor: ds2sf (Claude). Every pin and dimension is cited to a datasheet page; it refuses to fabricate.
  • CAD: KiCad official libraries (CC-BY-SA 4.0).

Datasheet PDF

Symbol & Footprint

Schematic Symbol

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PCB Footprint

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