MAXIM MAX31341CETB+T

The MAX31341B/MAX31341C low-current, real-time clock (RTC) is a time-keeping device that provides nanoamperes time-keeping current, extending battery life. The MAX31341B/ MAX31341C supports 6pF high-ESR crystals, which broaden the pool of usable crystals for the devices. This device is accessed through an I2C serial interface. The device features one digital Schmitt trigger input and one programmable threshold analog input. The device generates an interrupt output on a falling or rising edge of the digital input (D1), or when the analog input (AIN) voltage crosses a programmed threshold in either direction. An integrated power-on reset function ensures deterministic default register status upon power-up.

Other features include two time-of-day alarms, interrupt outputs, a programmable square-wave output, a serial bus timeout mechanism, and a 64-byte RAM for user data storage. The clock/calendar provides seconds, minutes, hours, day, date, month, and year information. The date at the end of the month is automatically adjusted for months with fewer than 31 days, including corrections for leap year. The clock operates in 24-hour format. The MAX31341B/MAX31341C also includes an input for synchronization. When a reference clock (e.g., 32kHz, 50Hz/60Hz Power Line, GPS 1PPS) is present at the CLKIN pin and the enable external clock input bit (ECLK) is set to 1, the MAX31341B/ MAX31341C RTC is frequency-locked to the external clock and the clock accuracy is determined by the external source.

The device is available in a lead(Pb)-free/RoHS-compliant, 12-pin, 2mm×1.5mm WLP with 0.5mm pitch and a 10-pin, 3mm x 3mm TDFN. The device supports the -40°C to +85°C extended temperature range.

• 180nA Timekeeping Current
• Wide Range of External Crystals with CL=6pF and ESR up to 100kΩ for Minimal Current Draw
• Trickle Charger for External Super Capacitor or Rechargeable Battery
• Provides Flexible Configurability
• A Schmitt Trigger Input to Trigger Interrupt
• One Analog Input with Adjustable Threshold to Trigger Interrupt
• Programmable Square-Wave Output for Clock Monitoring
• Saves Board Space
• Integrated Load Capacitors for Crystal Oscillator
• 2mm x 1.5mm, 12-Bump WLP with 0.5mm Pitch
• 3mm x 3mm, 10-pin TDFN
• Value Add Features for Ease-of-Use
• +1.6V to +3.6V Operating Voltage Range
• Countdown Timer with Repeat and Pause Functions
• 64-Byte RAM for User Data Storage
• Integrated Protection
• Power-On Reset for Default Configuration
• Automatic Switchover to Backup Battery or Super Capacitor on Power Fail
• Lockup-Free Operation with Bus Timeout

• Medical
• Wearables
• Point-of-Sale (POS)
• Telematics
• Portable Instruments
• Portable Audio