Features

• 500nA Quiescent Current
• ±1.5% (Max) Accuracy over Temperature
• Integrated Precision Attenuators
• Eight Pin-Selectable Reset Thresholds
• Eight Pin-Selectable Power-Fail Thresholds
• Early Warning Power-Fail Output
• 200ms Reset Timeout
• Manual Reset Input
• Compact 8-Lead, 2mm × 2mm DFN and TSOT-23 (ThinSOT) Packages

Typical Application

Description

The LTC2935 ultra-low power voltage monitor provides system initialization, power-fail warning and reset generation functions. Low quiescent current (500nA typical) makes the LTC2935 an ideal choice for battery-operated applications.

Three binary threshold-select inputs configure one of eight integrated reset thresholds, ranging from 1.6V to 3.45V in pre-determined increments. Early warning of an impending low voltage condition is provided at the powerfail output (PFO), whose threshold is above the configured reset threshold. Supervisory circuits monitor V_CC and pull RST low when V_CC drops below the configured reset threshold. When V_CC is rising from an under-threshold condition, an internal reset timer is started after exceeding the reset threshold by 5%. A 200ms reset timeout delays the return of the RST output to a high state. A pushbutton switch connected to the MR input is typically used to force a manual reset. Outputs RST and PFO are available with open-drain (LTC2935-1/LTC2935-3) or active pull-up (LTC2935-2/LTC2935-4) circuits. Operating temperature range is from –40°C to 85°C.