Key facts
- Brand
- Maxim
- Model
- DS1990A
- Industry
- Industrial
- Documents
- 3
- Languages
- EN · ZH
- Last added
- 2012-05-08
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Maxim DS1990A Serial Number iButton Handbook
The DS1990A Serial Number iButton is a rugged data carrier that provides a unique 64‑bit registration number for automatic identification. It operates over a single 1‑Wire data line and is used in access control, inventory control, tool management and other applications. The device is housed in a stainless‑steel, coin‑shaped package that can be mounted on a wide range of objects.
The handbook details the physical and electrical specifications, the 1‑Wire bus system, hardware configuration, transaction sequences, and timing diagrams required for reliable communication. It also lists ordering information, accessories, and safety compliance.
Maxim DS1990A specifications
| Operating Voltage Range | 2.8 V to 6.0 V |
|---|---|
| Operating Temperature Range | -40 °C to +85 °C |
| Weight | ≈ 2.5 g |
| Safety Standard | UL#913 (4th Edit.) |
All Maxim DS1990A documents by type
Day-to-day operation, settings and troubleshooting. Start here if the product is already set up.
Questions answered in these manuals
What unique identifier does the DS1990A have?
Each DS1990A is factory‑lasered with a guaranteed unique 64‑bit registration number.
How fast can the DS1990A be read?
The device can be read in less than 5 ms.
What unique identifier does the DS1990A contain?
Each DS1990A includes a factory‑programmed unique 64‑bit registration number.
How many bits are in the DS1990A ROM code?
The ROM code is 64 bits long, consisting of an 8‑bit family code, a 48‑bit serial number, and an 8‑bit CRC.
What unique identifier does the DS1990A contain?
Each DS1990A includes a factory‑etched unique 64‑bit registration number.
What is the maximum data transmission speed of the DS1990A?
The device can transmit data at up to 16.3 kbps.