Maxim Integrated MAX6426UK39: Microprocessor Reset Circuit

The MAX6426UK39 from Maxim Integrated is a high-precision microprocessor (µP) supervisory circuit designed to monitor power supplies in digital systems. It provides a crucial function by ensuring that the µP and its peripherals are reset properly during power-up, power-down, and brown-out conditions. The device maintains system integrity by preventing code execution errors during these critical times.

This supervisory circuit features a factory-trimmed reset threshold voltage of 3.9V, making it ideal for 5V systems that require a higher threshold to accommodate for tolerances and transients. The MAX6426UK39 offers an active-low reset output, which remains asserted for a minimum of 140ms after V_CC has risen above the reset threshold level. This ensures that the µP has sufficient time to stabilize and start up correctly.

One of the key features of the MAX6426UK39 is its low power consumption, with a typical supply current of only 1.2µA. This makes it an excellent choice for portable and battery-operated applications where power efficiency is paramount. The device is designed to operate over a wide voltage range, from 1.2V to 5.5V, providing versatility for different system designs.

The MAX6426UK39 comes in a compact SOT23-5 package, which is highly suited for space-constrained applications. Its small footprint allows for integration into various system designs without significantly impacting the overall size of the product.

Additional features include an immunity to short V_CC transients, which helps to prevent false resets and ensures reliable operation of the connected µP system. The device's robustness is further enhanced by its ability to operate over the extended temperature range of -40°C to +125°C, making it suitable for industrial and automotive applications where extreme temperatures are common.

In summary, the Maxim Integrated MAX6426UK39 is a reliable, low-power microprocessor reset circuit that offers precise voltage monitoring with minimal external components. Its robust feature set and compact packaging make it an excellent choice for designers looking to enhance the reliability and performance of their digital systems.