CAT859TTBI-GT3

Supervisors Overview

The CAT859TTBI-GT3 is a single-channel voltage supervisory circuit manufactured by onsemi, designed to monitor power supply rails in digital systems. It operates within a supply voltage range of 1.2 V to 5.5 V and features a fixed threshold voltage of 3.08 V. The device provides an active-low push-pull reset output with a standard reset delay time of 240 ms. It is housed in a compact SOT-23-3 surface-mount package and supports operation across an industrial temperature range from -40°C to +85°C. The component draws a typical operating current of 20 µA and does not include manual reset, watchdog timer, or battery backup switching functions.

Supervisors Feature Summary

• Provides a dedicated reset signal when the monitored supply voltage drops below the specified threshold level
• Features an active-low push-pull output driver capable of sourcing and sinking current directly
• Incorporates internal circuitry to ignore fast transients on the power supply line
• Ensures correct output state stability even at low supply voltages down to 1.0 V

Supervisors Applications

• Monitoring power rails in embedded digital control systems
• Supervising voltage levels in industrial instrumentation equipment
• Providing reset signals for microcontrollers and logic circuits
• Ensuring system reliability in consumer electronics power management

Supervisors Procurement Notes

Verify the obsolete status and end-of-life designation before procurement planning. Confirm availability of parametric equivalents or substitute part numbers from onsemi or third-party distributors. Ensure the SOT-23-3 package footprint matches the target PCB design. Validate that the 3.08 V threshold meets the specific application requirements. Check for RoHS compliance documentation as indicated in official specifications.

Supervisors Selection Notes

Select this component when a fixed 3.08 V threshold is required for monitoring lower voltage rails within the 1.2 V to 5.5 V range. The active-low push-pull output is suitable for direct interfacing with most digital inputs. Consider the 240 ms reset delay for timing-sensitive applications. The low quiescent current makes it appropriate for battery-powered devices where standby consumption must be minimized. Verify thermal performance within the -40°C to +85°C operating range.

Supervisors Part Context

The CAT859TTBI-GT3 belongs to the CAT809 series of voltage supervisors from onsemi. This family offers various fixed threshold options to support common system voltages such as +5.0 V, +3.3 V, +3.0 V, and +2.5 V. The CAT809 series is designed to replace legacy parts like the MAX809 in industrial applications. The TTBI suffix indicates the specific 3.08 V threshold variant in the SOT-23-3 package.

Supervisors Replacement Considerations

Publicly confirmed substitutes include parametric equivalent parts listed by distributors. Verify compatibility of threshold voltage, output polarity, and package dimensions. Check if alternative manufacturers offer functionally identical components with updated lifecycle status.