MAX6457 Datasheet

• Wide Supply Voltage Range, 4V to 28V
• Internal 2.25V ±2.5% Reference
• Low Current (3.5µA, typ at 12V)
• Open-Drain n-Channel Output (28V Compliant)
• Internal Threshold Hysteresis Options (0.5%)
• Two IN-to-OUT Timeout Period Options (50µs, 150ms)
• Internal Undervoltage Lockout
• Immune to Short Voltage Transients
• Small SOT23 Packages
• Few External Components
• Fully Specified from -40°C to +125°C
• Enables Functional Safety at System Level

• Automotive
• Industrial
• Multicell Battery-Stack Powered Equipment
• Networking
• Notebooks, eBooks
• Overvoltage Monitoring/Protection
• Telecom
• Undervoltage Monitoring/Shutdown
• Window Voltage Detection Circuitry

The MAX6457 high supply voltage, low-power voltage monitors operate over a 4V to 28V supply voltage range. Each device includes a precision bandgap reference, one or two low-offset voltage comparators, internal threshold hysteresis, power-good or reset timeout options, and one or two high-voltage open-drain outputs. Two external resistors (three for window detection) set the trip threshold voltages.

The MAX6457 is a single voltage monitor for undervoltage or overvoltage detection. A logic-based clear input either latches the output for overvoltage applications or allows the device to operate in transparent mode. The inverting and noninverting inputs of the comparator are externally accessible to support positive or negative voltage monitors and to configure the device for active-high or active-low output logic.

The MAX6457 offer fixed timing options as a voltage detector with a 50µs typical delay or as a reset circuit with a 90ms minimum reset timeout delay. The monitored input must be above the adjusted trip threshold  for the selected timeout period before the output changes state. Internal threshold hysteresis options (0.5% for the MAX6457) reduce output chatter in noise-sensitive applications. Each device is available in a small SOT23 package and specified over the extended temperature range of -40°C to +125°C.