The MAX4505 is a single signal-line protector featuring a fault-protected input and rail-to-rail signal handling capability. The input is protected from overvoltage faults up to ±36V with power on or ±40V with power off. During a fault condition, the input terminal becomes an open circuit and only nanoamperes of leakage current flow from the source, while the switch output (A_OUT) furnishes typically 19mA from the appropriate polarity supply to the load. This ensures an unambiguous rail-to-rail output when a fault begins and ends.

The MAX4505 protects both unipolar and bipolar analog signals using either unipolar (+9V to +36V) or bipolar (±8V to ±18V) power supplies. The device has no logic control inputs; the protector is always on when the supplies are on. On-resistance is 100Ω max, and on-leakage is less than 0.5nA at T_A = +25°C. The MAX4505 is available in 5-pin SOT23 and 8-pin µMAX® packages.

Applications

• Automated Test Equipment (ATE)
• Data Acquisition
• Hot-Insertion Boards/Systems
• Process Control Systems
• Redundant/Backup Systems
• Sensitive Instruments