DS3234 Extremely Accurate RTC with SPI Bus, Integrated Crystal, and SRAM
The DS3234 is an extremely accurate real-time clock (RTC) with a SPI™ bus control interface. The device is Maxim's first accurate RTC with an SPI interface specifically designed for use with Motorola® processors.
The DS3234 is a highly stable TCXO combined with an RTC. It integrates 256 bytes of user-configurable SRAM, a digital temperature sensor, and a crystal at a low cost. No user calibration is required to achieve accuracies of better than ±1.8min/yr (< ± 3.5ppm) over the extended industrial temperature range (-40°C to +85°C) and better than ±1min/yr (< ±2.0ppm) for the 0°C to +40°C temperature range.
The DS3234 is designed for low-power applications, supports supply voltages ranging from +2.2V to +5.5V, and provides automatic switching to secondary supplies such as low-voltage batteries. Access to time, temperature, and memory is accomplished through the standard SPI control interface. The user only needs to supply a 3V backup energy source to maintain time in the absence of system power, and a host processor to access time, temperature, and/or memory through the SPI control interface. The DS3234 is packaged in a standard 20-pin 300 mil SO for ease of handling and manufacturing.
Typical applications for the DS3234 include telematics, GPS, electricity meters, fleet management, servers, security-/access-control systems, time-based billing systems, POS systems, and ATMs.
Key Features
±1.8min/yr Accuracy (-40°C to +85°C)
Real-Time Clock Counts Seconds, Minutes, Hours, Day, Date, Month, and Year with Leap Year Compensation Valid Up to 2100