2-pin, self-powered serial EEPROMs for IoT, battery, consumable & cable ID

August 11, 2015 // By Graham Prophet
Using a parasitic power scheme and I²C signalling, these single-wire memories require just one data and one ground pin, eliminating the need for power source/Vcc; they present a plug-and-play 64-bit serial number for identification

Atmel aims the parts at Internet of Things (IoT), wearables, consumable, battery and cable identification markets. The devices are self-powered, eliminating the need for a power source or Vcc pin, with a parasitic power scheme via the data pin. These devices draw ultra-low currents at standby of 700 nA: operating currents are 200 µA for write and 80 µA for read at 25C, claimed to be one third the power of alternatives.

With confined spacing in smaller IoT, wearables, battery and cable identification applications, Atmel’s AT21CS01 devices eliminate the need for external capacitors and rectifiers with its parasitic power scheme over a single data pin. The devices have an ultra-high write endurance capability to allow more than one million cycles for each memory location.

The AT21CS01 products include a simple product identification with a plug-and-play 64-bit unique serial number in every device, suiting the device for smart, connected devices including wearables such as smart fitness bands and healthcare devices. The devices also offer high electrostatic discharge (ESD) rating (IEC 61000-4-2 Level 4 ESD Compliant), so applications such as cables, consumables, etc. can tolerate exposure to the outside environment or direct human contact.

Atmel adds. “Our new Single-Wire EEPROM family makes it very convenient to add serial EEPROM using just one-pin from the MCU/MPU without the need to route the Vcc to the device, delivering significant board space saving and simplifying the layout. In addition, the plug-and-play 64-bit serial number is the easiest way to add identification to various accessories and consumables.”

The new devices use the I ²C protocol, allowing for an easy migration from existing EEPROM with less overhead and capability to connect up to eight devices on the same bus. The AT21CS01 devices offer a security register with a 64-bit factory programmed serial number and extra 16 Bytes of user programmable and permanently lockable storage, delivering a guaranteed unique serial number for inventory tracking or asset tagging,