The document describes a product with 4096 bits of read/write nonvolatile memory and 1024 bits of read/write nonvolatile memory. The product features a 256-bit scratchpad to ensure data transfer integrity. The memory is partitioned into 256-bit pages for packetizing data. Strict read/write protocols ensure data integrity. The product has an operating temperature range of -40°C to +70°C and data retention of over 10 years.
The DS1992 and DS1993 are rugged, read/write memory iButtons that store 1024 bits (DS1992) or 4096 bits (DS1993) of non‑volatile data. Each device includes a unique 64‑bit laser‑etched ROM, a 256‑bit scratchpad buffer, and SRAM memory organized into 32‑byte pages. The iButton package is a compact, stainless‑steel MicroCan that can be mounted on objects, key fobs, badges or PC boards.
Operation uses the 1‑Wire protocol with parasite power. Data is first written to the scratchpad, verified, and then copied to memory via the copy‑scratchpad command. The handbook provides detailed command flow charts, memory maps, electrical characteristics, and physical specifications such as operating temperature range, voltage limits, and safety ratings.
| Operating Temperature Range | -40 °C to +70 °C |
|---|---|
| Weight (F5 package) | 3.3 g |
| Maximum Voltage on any Pin | -0.5 V to +7.0 V |
| I/O Capacitance (1‑Wire) | 100 pF – 800 pF |
It operates from –40 °C up to +70 °C.
Pins may be driven from –0.5 V to +7.0 V relative to ground.