DS1344D-3+T&R

Real Time Clock Overview

The DS1344D-3+T&R is a low-current real-time clock (RTC) IC manufactured by Analog Devices Inc./Maxim Integrated. It provides timekeeping and calendar functions including seconds, minutes, hours, day, date, month, and year with leap year compensation valid through 2099. The device supports SPI or 3-wire serial interfaces and includes two programmable alarms with interrupt outputs. It features 96 bytes of battery-backed NV RAM. Electrical specifications include a VCC operating range of 2.7V to 5.5V and a VBAT range of 1.3V to 5.5V. Timekeeping current is typically 250nA. The component is housed in a 20-pin TSSOP package and operates within an extended industrial temperature range of -40°C to +85°C.

Real Time Clock Feature Summary

• Integrated capacitive loading for 12.5pF crystals
• Supports high-ESR crystals up to 100kΩ
• Two programmable time-of-day alarms with interrupt outputs
• 96-byte battery-backed non-volatile RAM

Real Time Clock Applications

• Embedded timestamping
• Medical devices
• Handheld devices
• Telematics systems

Real Time Clock Procurement Notes

Verify the specific suffix D-3 corresponds to the 2.7V–5.5V voltage variant and 20-pin TSSOP package as defined in the official datasheet. Confirm RoHS compliance status and lead-free material declarations prior to procurement. Ensure the ordering suffix matches the required interface mode configuration and packaging type specified in the manufacturer's documentation.

Real Time Clock Selection Notes

Select the DS1344D-3 variant specifically when the application requires integrated capacitive loading for 12.5pF load capacitance crystals. This model differs from the DS1343 series which supports 6pF crystals. Verify that the system power supply remains within the 2.7V to 5.5V range for VCC. Ensure the design accommodates the 20-pin TSSOP footprint and supports either SPI or 3-wire serial communication protocols.

Real Time Clock Part Context

The DS1344D-3+T&R belongs to the DS1343/DS1344 family of low-current RTCs. The 'D' indicates the 2.7V nominal voltage version, while 'DS1344' denotes support for 12.5pF crystals compared to the DS1343's 6pF support. The '+T&R' suffix indicates tape and reel packaging. This family is designed for applications requiring minimal standby current and robust crystal drive capabilities.

Real Time Clock Replacement Considerations

The DS1343E-3+T&R is a functional substitute if the application utilizes 6pF crystals instead of 12.5pF. Both share identical pinouts, interfaces, and electrical characteristics except for the internal oscillator loading capacitance. Verify crystal compatibility before substitution.