Maxim Integrated's MAX809LESA+T Microprocessor Reset Circuit

The MAX809LESA+T is a compact, highly reliable microprocessor (µP) supervisory circuit designed to monitor power supplies in digital systems. Manufactured by Maxim Integrated, a leader in analog and mixed-signal engineering, this component ensures that the µP and its peripherals are reset properly during power-up, power-down, or brown-out conditions. Its main role is to safeguard your system's integrity by providing a precise, factory-trimmed threshold voltage for power failure detection.

This supervisory circuit comes in a 3-pin SOT-23 package, which is ideal for space-constrained applications. The MAX809LESA+T operates with a supply voltage range from 1.0V to 5.5V, making it versatile for various low-voltage applications. Additionally, it offers a low supply current of 17µA (typical), which is beneficial for power-sensitive designs.

One of the key features of the MAX809LESA+T is its ability to assert a reset signal whenever the V<sub>CC supply voltage drops below the preset threshold. The reset output remains asserted for a period of at least 140ms after V<sub>CC has risen above the reset threshold level, ensuring that the system has adequate time to stabilize.

The device also provides an active-low RESET output, which gives you the flexibility to interface with a variety of microprocessors that require an active-low input for reset. Its push-pull output stage eliminates the need for an external pull-up resistor, which simplifies the design and reduces component count.

The MAX809LESA+T is designed for a broad range of applications, including computers, controllers, intelligent instruments, portable/battery-powered equipment, and embedded systems. Its robust design ensures reliable operation over the automotive temperature range of -40°C to +125°C.

Choosing the MAX809LESA+T for your design means selecting a product with the quality and performance expected from Maxim Integrated. It is a simple, cost-effective solution for enhancing system reliability and preventing the unpredictable behavior caused by improper power-up and power-down sequences.