Texas Instruments Voltage Detector IC, 3.08V Threshold, 240ms Delay, SOT-23

The Texas Instruments LM809M3-3.08/NOPB is a compact 3-pin microprocessor supervisory circuit, engineered to monitor power supply voltages in digital and microprocessor-based systems. It ensures reliable operation by providing a controlled reset signal during critical power events such as initial power-up, power-down, and brownout conditions, where the supply voltage dips below its operational threshold.

This active-low reset IC continuously monitors the VCC supply. It asserts a reset signal whenever the voltage falls below its factory-programmed threshold of 3.08V. The reset condition is maintained for a precise 240ms delay after VCC recovers and stabilises above the threshold, guaranteeing the microprocessor has adequate time to initialise correctly. This function is vital for preventing data corruption and erratic behaviour in sensitive electronic applications.

Designed for efficiency and reliability, the IC features a typical low supply current of just 15µA, making it suitable for portable and battery-powered devices. It offers robust power supply transient immunity and is fully specified over a wide operating temperature range from -40°C to 105°C. Furthermore, the RESET output is ensured to be valid for VCC as low as 1V, providing an extra layer of system protection.

Key Features & Benefits

• Active-Low Reset Output: Provides a clear reset signal to the host microprocessor.
• Precise Voltage Monitoring: Factory-set reset threshold voltage of 3.08V.
• Guaranteed Reset Pulse: 240ms delay after voltage recovery ensures stable system start-up.
• Low Power Consumption: Typical supply current of 15µA conserves energy in portable applications.
• Robust Design: Features power supply transient immunity and a wide operating temperature range.
• Compact SMD Package: Supplied in a space-saving SOT-23-3 surface-mount package for high-density PCB designs.