MAX807NEPE+

MAX807NEPE+ Application Field and Working Principle

The MAX807NEPE+ is a PMIC (Power Management Integrated Circuit) within the Supervisors category. It is an integrated circuit that provides the basis for power management and supply regulation. It is designed to monitor voltages, current and temperature to maintain the proper power levels within a device and to shut down the system if an over-voltage, over-current or over-temperature condition is detected. This safety feature reduces the product life cycle time and increases the reliability of the device.

Product Overview

The MAX807NEPE+ is a low-voltage supervisor with an ultra-low operating current of only 4µA. It has an internal voltage reference, a comparator and hysteresis to accurately detect falling and rising voltages. The device supports an adjustable reset delay to accommodate long power-up times for the supply voltage system. The MAX807NEPE+ also includes an accuracy of ±2% and temperature compensation.

In addition, this device includes a low-voltage reset output and an optional manual reset input. The reset output is generated every time an under-voltage or over-voltage condition is detected. It is normally in the high-impedance state and is activated low when a reset event occurs. The MAX807NEPE+ can also be manually reset by the RESET pin to restart the initialization cycle.The MAX807NEPE+ features an open-drain reset output, adjustable reset delay and a high-accuracy voltage reference.

Applications

Typical applications for the MAX807NEPE+ include voltage/current monitoring and protection, power-on reset (POR) and power-fail warning (PFW) systems. It is also used in personal computers, modems, embedded systems, and medical instrumentation. It provides an adjustable delay from a few milliseconds to several minutes, making it well suited for applications where long initializations are required.

Features and Benefits

• Ultra-low operating current of 4µA.
• Supports an adjustable reset delay.
• Accurate reset threshold of ±2%.
• Open-drain reset output.
• Low-voltage reset.
• Optional manual reset input.

Pin Functions

The MAX807NEPE+ is available in an 8-pin SOP package. The pin functions of the device are listed below:

• VCC: Power supply pin.
• GND: Ground pin.
• VREFA: Adjustable voltage reference input.
• VREF: Voltage reference output.
• CT: Comparator input.
• RESET: Reset output.
• MORESET: Manual reset input (active low).
• T: Temperature sensor input.

Working Principle

The MAX807NEPE+ constantly monitors the power supply and other signals within the system. When the input voltage falls below or rises above the set threshold, the MAX807NEPE+ will generate a reset response. The RESET pin will transition low and remain low until the voltage returns within the set threshold. The reset pulse duration is determined by the resistive network across CT and VREF pins.

The MAX807NEPE+ includes an on-chip temperature compensation to reduce the number of external components and to enhance the reliability of the system. The temperature compensation allows the MAX807NEPE+ to monitor the temperature of the system and adjust the reset threshold accordingly, reducing the possibility of false resets.

Conclusion

The MAX807NEPE+ is a versatile PMIC that is ideal for a wide range of applications. It offers an ultra-low operating current and an adjustable reset delay, making it well suited for applications that require long initializations. The device also features a low-voltage reset output and an optional manual reset input. This device is available in an 8-pin SOP package and is suitable for portable devices, embedded systems, and medical instrumentation.