MAX704TESA+

Power Management Integrated Circuits (PMICs) are sophisticated semiconductor devices designed to manage, monitor and regulate the power on various host systems. Among these devices is the Supervisors, which are a class of circuits designed for the orderly start-up of the system and protection of the core components of the system. The MAX704TESA+ is one such circuit that belongs to this family, and this paper will explore its application field and working principle.

Application Field

The MAX704TESA+ is a low-voltage, single-chip supervisor used in portable electronic devices. It provides supply voltage monitoring and reset signal to ensure reliable start-up and system functioning. It is used in a variety of automotive applications, including car navigation and audio systems, vehicle immobilizers, airbag systems and climate control. The MAX704TESA+ is also suited for battery-powered applications like payment terminals, medical, test and measurement, and consumer applications.

Working Principles

The MAX704TESA+ is a highly integrated IC with a built-in low-voltage detection circuitry to protect the system from low-voltage conditions. It accurately monitors the power supply voltage and provides an output signal on the RESET pin. The supervisor also ensures that the voltage on the VCC pin rises above the reset threshold level before the device starts operating. The reset signal is provided whenever the supply voltage falls below the reset threshold voltage for a duration specified by the timeout period. The input voltage levels are monitored by an internal comparator circuit, and the reset period can be adjusted by adjusting a single external capacitor. The reset period can be varied from milliseconds to hours, and the programmable reset time can be changed easily.

The MAX704TESA+ has an in-built watchdog timer, which is employed to guard against system hangs and lockups. The timer is reset periodically, typically by toggling an input line. This prevents system lockups due to software bugs or other unforeseen events. The supervisor also provides power-up and power-down sequencing, ensuring proper ordering of power sources, thus protecting the core components in the system.

Conclusion

The MAX704TESA+ is a highly integrated single-chip supervisor ideal for a variety of applications in the automotive and consumer fields. Its low voltage protection and reset function, together with its programmable reset and watchdog timer, makes it suitable for a host of systems, ranging from automotive applications like vehicle immobilizers and climate control to battery powered devices like payment terminals and medical equipment.