DS1302Z

Overview

The DS1302Z+ is a trickle-charge real-time clock (RTC) and calendar integrated circuit manufactured by Analog Devices Inc./Maxim Integrated. It provides seconds, minutes, hours, date, month, day of the week, and year information with leap-year compensation valid up to the year 2100. The device features a simple 3-wire serial interface compatible with TTL logic at 5V. It includes 31 bytes of battery-backed static RAM for general-purpose data storage. Operating on a supply voltage range of 2.0V to 5.5V, it consumes less than 300nA at 2.0V. The component is housed in an 8-pin SOIC package with a width of 3.90mm.

Feature Summary

• Real-Time Clock/Calendar: Counts seconds, minutes, hours, date, month, day of week, and year with automatic leap-year adjustment.
• Battery-Backed RAM: Includes 31 x 8 bytes of static RAM accessible via the serial interface.
• Low Power Operation: Operates from 2.0V to 5.5V with timekeeping current under 1µA at 5V.
• Simple Interface: Uses a synchronous 3-wire serial port (CE, I/O, SCLK) for communication.

Applications

• Portable instruments requiring precise timekeeping
• Data logging systems needing timestamp capabilities
• Embedded controllers with limited I/O resources

Procurement Notes

Verify the specific suffix against the manufacturer's ordering guide. The 'Z' indicates an 8-pin SO package (150 mils), while 'N' denotes industrial temperature range (-40°C to +85°C). Confirm RoHS compliance status as indicated by the '+' suffix. Ensure the required operating temperature range matches the commercial grade (0°C to +70°C) specified for this part number.

Selection Notes

Select the DS1302Z+ when a low-cost, low-power RTC with minimal pin count is required. It supports both single-byte and burst-mode data transfers. Ensure the application can provide a stable 32.768kHz crystal load capacitance of 6pF. For environments exceeding 70°C, consider the industrial grade variant DS1302ZN+.

Part Context

The DS1302 series serves as a successor to the DS1202, adding dual power pins and programmable trickle charging capabilities. The DS1302Z specifically refers to the commercial temperature grade device in the 8-pin Small Outline package. It is widely used in applications where space constraints and low power consumption are critical design factors.

Replacement Considerations

For industrial temperature requirements (-40°C to +85°C), use DS1302ZN+. For DIP packaging, consider DS1302+ or DS1302N+. Verify that replacement parts maintain compatibility with the 3-wire serial protocol and BCD data format.