The MAX4506/MAX4507 multiple, two-terminal signal-line protectors are pin-compatible with the industry-standard MAX366/MAX367. These new circuit protectors feature fault-protected inputs and rail-to-rail signal handling capability. The input pins are 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; but the switch output (OUT_) furnishes typically 19mA from the appropriate polarity supply to the load. This ensures unambiguous rail-to-rail outputs when a fault begins and ends.The MAX4506 contains three independent protectors while the MAX4507 contains eight independent protectors. They can protect both unipolar and bipolar analog signals using either unipolar (+9V to +36V) or bipolar (±8V to ±18V) power supplies.These devices have no logic control inputs; the protectors are designed to be always-on when the supplies are on. On-resistance is 100Ω max and matched within 7Ω , and on-leakage is less than 0.5nA at TA= +25°C. The MAX4506 is available in 8-pin SO/DIP packages. The MAX4507 is available in 20-pin SSOP and 18-pin SO/DIP packages.ApplicationsAutomated Test Equipment (ATE)Data Acquisition SystemsHot-Insertion Boards/SystemsProcess Control SystemsRedundant/Backup SystemsSensitive Instruments