MAX16021PTES+

The MAX16016/MAX16020/MAX16021 supervisory circuits monitor power supplies, provide battery-backup control, and chip-enable (CE) gating to write protect memory in microprocessor (µP)-based systems. These low-power devices improve system reliability by providing several supervisory functions in a small, single integrated solution. The MAX16016/MAX16020/MAX16021 perform four basic system functions: 1) Provide a µP reset output during VCC supply powerup, power-down, and brownout conditions. 2) Control VCC to battery-backup switching internally to maintain data or low-power operation for memories, real-time clocks (RTCs), and other digital logic when the main power is removed. 3) Provide memory write protection through internal chip-enable gating during brownout. 4) Provide a combination of additional supervisory functions listed in the Features section. The MAX16016/MAX16020/MAX16021 operate from a 1.53V to 5.5V supply voltage and offer fixed reset thresholds for monitoring 5V, 3.3V, 3V, 2.5V, and 1.8V systems. Each device is available with either a pushpull or open-drain reset output. The MAX16016/MAX16020/MAX16021 are available in small TDFN/TQFN packages and are fully specified for an operating temperature range of -40°C to +85°C.

Applications

• Main/Backup Power for RTCs, CMOS Memories
• Industrial Control
• GPS Systems
• Set-Top Boxes
• Point-of-Sale Equipment
• Portable/Battery Equipment

Key features

• System Monitoring for 5V, 3.3V, 3V, 2.5V, or 1.8V Power-Supply Voltages
• 1.53V to 5.5V Operating Voltage Range
• Low 1.2µA Supply Current (0.25µA in BatteryBackup Mode)
• 145ms (min) Reset Timeout Period
• Battery Freshness Seal
• On-Board Gating of CE Signals, 1.5ns Propagation Delay (MAX16020/MAX16021)
• Debounced Manual Reset Input
• Watchdog Timer, 1.2s (typ) Timeout
• Power-Fail Comparator and Low-Line Indicator for Monitoring Voltages Down to 0.6V
• Battery-On, Battery-OK, and Battery Test Indicators
• Small 10-Pin TDFN or 16-Pin TQFN Packages
• UL-Certified to Conform to IEC 60950-1