Maxim Integrated MAX708SD Microprocessor Supervisory Circuit

The Maxim Integrated MAX708SD is a highly reliable microprocessor (μP) supervisory circuit designed to monitor power supplies and microprocessor activity in digital systems. It provides excellent circuit reliability and low cost by eliminating external components and adjustments when used in a variety of electronic applications.

This compact supervisory circuit ensures that the μP is reset to a known state during power-up, power-down, or brown-out conditions. The MAX708SD features an active-low reset output, with the reset signal being asserted when the VCC supply voltage drops below the reset voltage threshold. The reset output remains asserted for a reset timeout period after VCC rises above the reset threshold, ensuring the system has sufficient time to stabilize before the processor starts executing code.

The MAX708SD offers a factory-trimmed reset threshold voltage, which allows users to select a device tailored to their specific voltage requirements. This feature simplifies design considerations and enhances system reliability by providing precision voltage monitoring without the need for external components.

Additional features of the MAX708SD include a manual reset input, which provides a hardware override of the reset output. This allows for a system reset to be triggered with an external switch or logic signal, which can be useful for debugging or during routine maintenance.

Designed with a low supply current, the MAX708SD is suitable for battery-operated applications where power efficiency is critical. The device comes in a space-saving 8-pin SO package, which is ideal for systems where PCB real estate is at a premium.

Overall, the Maxim Integrated MAX708SD supervisory circuit is an essential component for managing system integrity. Its combination of features, including reset threshold options, manual reset capability, and low power consumption, make it a versatile choice for ensuring the reliable operation of microprocessor-based systems.

Key specifications include:

• Reset Threshold Options: Factory-trimmed to specified requirements
• Reset Timeout: 200ms (min) reset pulse width
• Supply Voltage Range: 1.0V to 5.5V
• Supply Current: 17μA (typ)
• Package Type: 8-pin SO