MAX16056, MAX16057, MAX16058, MAX16059 125nA supervisory circuits extend battery life in portable electronics

125nA microprocessor supervisory circuits have the lowest power in their class.

Maxim's new low-power supervisors feature capacitor-adjustable reset and watchdog timeouts to enable unique power-saving schemes.

SUNNYVALE, CA—August 24, 2009—Maxim Integrated Products introduces the MAX16056–MAX16059, ultra-low-power microprocessor supervisory circuits that monitor a single system supply voltage. These devices consume an industry-low 125nA supply current to extend battery life in power-sensitive applications.

Additionally, the devices feature capacitor-adjustable watchdog (MAX16056/MAX16058) and reset timeouts to maximize design flexibility. This configurability makes it easy for designers to quickly change design parameters, and enables the supervisors to be used in unique power-saving schemes.

Because of their ultra-low power consumption and flexible timeout configuration, these devices can be utilized in multiple ways within the system while saving valuable board space. The MAX16056–MAX16059 are well suited for battery-powered devices, handheld electronics, metering equipment, and other applications where battery life is crucial.

Extending Battery Life in Portable Devices

Many microprocessors in battery-powered systems spend the vast majority of their time in standby/sleep mode, only waking up periodically to perform a required function. In these applications, standby current consumption is often the most important factor in determining battery life, as the application may spend as much as 99% of the day in sleep mode.

To minimize system power consumption in these applications, the MAX16056–MAX16059 can be used to periodically wake up the processor to complete its required duties, and then turn off the processor when those functions are complete. At a mere 125nA, the operating supply current of these supervisory circuits is much lower than the standby supply current of a typical microcontroller (> 1µA). The MAX16056–MAX16059, therefore, have a negligible impact on the application's power budget, effectively reducing system shutdown current to zero. Altogether, these supervisors can increase battery life by several months in low-power applications.

The MAX16056–MAX16059 can also be used as low-power oscillators to conserve energy, as they consume much less power than integrated adjustable oscillators.

Functional Details

The MAX16056–MAX16059 can monitor voltages from 1.575V to 4.625V. These devices assert a reset signal whenever the V_CC supply voltage drops below the reset threshold, manual reset is pulled low, or the watchdog timer (MAX16056/MAX16058) runs out. The reset function features immunity to power-supply transients.

Additional Information

The MAX16056–MAX16059 operate from a 1.1V to 5.5V voltage range, and are available in either push-pull or open-drain output configurations. A manual-reset input facilitates testing.

All devices are fully specified over the -40°C to +125°C automotive temperature range. The MAX16056/MAX16058 are available in a 3mm x 3mm, 8-pin TDFN package, and the MAX16057/MAX16059 are available in a 3mm x 3mm, 6-pin TDFN package. Prices start at $1.10 (1000-up, FOB USA). Samples are now available.