STMicroelectronics Debuts Supervisor Chips

STMicroelectronics (Geneva) announced two full-featured supervisor chips that provide early warning of a power failure, thereby leaving time to save key data and initiate shutdown.

The M41ST84 and M41ST85 each come in 3V and 5V versions and are suited for applications such as medical systems, servers, point-of-sale terminals and SCSI peripherals. The reset output provides power-on reset and a low-voltage reset.

The M41ST84 built-in power sense circuit detects power failures and automatically switches to battery power. The early power-fail warning circuit, which contains a 1.25V precision reference and comparator, can alternatively be used to monitor a secondary supply in multiple voltage systems.

Both the M41ST84 and the M41ST85 draw a maximum of 500nA of battery current and only 400uA of supply current when active. The M41ST84 is available in a 16-pin SOIC package while the M41ST85 comes in the SNAPHAT 28-pin SOIC package.

The -Y versions of the M41ST84 and M41ST85 operate at supply voltages between 4.5V and 5.5V, and deselect at 4.4V ±0.10V; the -W versions operate at supply voltages between 2.7V and 3.6V and deselect at 2.625V ±0.075V. All operate over the industrial -40 to +85 degrees C temperature range. Sample units are available now.