MAX6439MAX6442

VBATT, VCC to GND.................................................-0.3V to +6V*
Open-Drain LBO, LBOH, LBOL, LBOLH to GND ...-0.3V to +6V*
Open-Drain RESET to GND ....................................-0.3V to +6V*
Push-Pull RESET to GND............................-0.3V to (VCC + 0.3V)
MR to GND .................................................-0.3V to (VCC + 0.3V)
Input/Output Current, All Pins .............................................20mA
Continuous Power Dissipation (TA = +70°C)
6-Pin SOT23 (derate 8.7mW/°C above +70°C)............695mW
8-Pin SOT23 (derate 8.9mW/°C above +70°C)............714mW
Operating Temperature Range .......................... -40°C to +85°C
Junction Temperature......................................................+150°C
Storage Temperature Range .............................-65°C to +150°C
Lead Temperature (soldering, 10s) .................................+300°C


Description

The MAX6439MAX6442 are a family of ultra-low-power battery monitors with integrated microprocessor (µP) supervisors. The battery monitors are offered with single or dual low-battery output options that can be used to signal when the battery is OK (enabling full system operation), when the battery is low (for low-power system operation), and when the battery is dead (to disable system operation). These MAX6439MAX6442 also have an independent µP supervisor that monitors VCC and provides an active-low reset output. 

A manual reset function is available to reset the µP with a push-button. No external components are required. The MAX6439MAX6442 are offered with several factory- trimmed low-battery threshold combinations ideal for single-cell lithium-ion (Li+) or multicell alkaline/NiCd/ NiMH applications. 

When the battery voltage of MAX6439MAX6442 drops below each specified low threshold, the low-battery outputs are asserted to alert the system. When the voltage rises above the specified high thresholds, the outputs are deasserted after a 150ms minimum timeout period, ensuring the voltages have stabilized before power circuitry is activated or providing microprocessor reset timing. 

The low and high thresholds provide hysteresis in battery-operated systems to eliminate output chattering. The MAX6439/MAX6440 offer factory-trimmed battery monitors with a single output. The MAX6441/MAX6442 offer factory-trimmed battery monitors with dual outputs. All battery monitors have open-drain low-battery outputs. The MAX6439MAX6442 monitor system voltages (VCC) from 1.8V to 3.3V with seven fixed reset threshold options. 

MAX6439MAX6442 is offered with two minimum reset timeout periods of 150ms or 1200ms. The MAX6439/ MAX6441 are offered with an open-drain RESET output and the MAX6440/MAX6442 are offered with a pushpull RESET output. The MAX6439MAX6442 are offered in a SOT23 package and are fully specified over a -40°C to +85°C temperature range.