The unique features of the LTC2934 and LTC2935 differentiate them in the low power monitor market and make them excellent choices for single Li+ coin cell, AA, AAA and other compact battery-powered or green applications. The LTC2935 has three binary inputs that allow selection of one of eight integrated reset thresholds, from 3.3V down to 2.25V in 150mV increments. The device’s internal precision attenuators allow the part to maintain only 500nA of supply current and accuracy. The LTC2934 allows an external resistive divider to finely set the reset threshold anywhere from 1.6V to 6V. The reset thresholds in both devices are +/-1.5% accurate over temperature which helps to minimize supply overdesign. An early warning of a threatening low voltage condition is provided via a power-fail output. The supervisory circuits monitor VCC and pull the reset output low if the supply voltage drops below the configured reset threshold. The LTC2934 includes two reset timeout-periods of 15ms or 200ms, settable via a time-out selection pin, while the LTC2935 offers a fixed 200ms timeout. A manual reset pin is also provided on both devices for optional use of a pushbutton switch to force a system reset.
The LTC2934 and LTC2935 have a variety of ordering options. Reset and power-fail outputs are available with open drain or active pull-up circuits. Commercial and industrial versions offer different operating temperature ranges, from 0°C to 70°C and -40°C to 85°C, respectively.