DS1673S-3

Real Time Clock Overview

The DS1673S-3 is a portable system controller from Analog Devices Inc./Maxim Integrated, housed in a 20-pin SO package. It integrates a real-time clock (RTC), nonvolatile RAM (NV SRAM) controller, microprocessor monitor, and a 3-channel, 8-bit analog-to-digital converter (ADC). The device operates at +3.0V with an operating temperature range of 0°C to +70°C. Communication utilizes a simple 3-wire serial interface. Key features include leap year compensation up to 2100, automatic battery backup for external SRAM via the VCCO pin, and watchdog timer functionality.

Real Time Clock Feature Summary

• Integrates RTC with alarm interrupt, NV SRAM controller, microprocessor monitor, and 3-channel 8-bit ADC
• Supports automatic battery backup and write protection for external SRAM through VCCO, CEOL, and CEOH pins
• Microprocessor monitor includes power-fail detection, pushbutton reset control, and configurable watchdog timer
• Operates on a +3.0V supply with a 3-wire serial interface (CS, SCLK, I/O)

Real Time Clock Applications

• Low-power portable products requiring integrated timekeeping and memory management
• Systems utilizing external SRAM that require automatic backup during power failures
• Applications needing microprocessor reset supervision and watchdog timer capabilities

Real Time Clock Procurement Notes

Verify the specific suffix 'S' corresponds to the 20-pin SO package rather than the TSSOP variant. Confirm the '-3' suffix indicates the +3.0V operating voltage version. Ensure compatibility with the required 3-wire serial interface timing specifications for the target microprocessor system.

Real Time Clock Selection Notes

Select this component when a single-chip solution for RTC, SRAM backup, and system monitoring is required. The DS1673S-3 is suitable for designs operating at +3.0V. Consider the 3-channel ADC if analog input monitoring is necessary. Verify that the external SRAM requirements align with the chip-enable outputs (CEOL/CEOH) provided by the device.

Real Time Clock Part Context

The DS1673S-3 belongs to the DS1673E family of portable system controllers. It shares functional similarities with the DS1673E-3 but differs in packaging. The 'S' designation specifically identifies the 20-pin Small Outline package, while the 'E' designation refers to the Thin Shrink Small Outline Package (TSSOP). Both variants offer identical electrical performance within the specified temperature range.

Real Time Clock Replacement Considerations

The DS1673E-3+ serves as a functional equivalent with identical electrical characteristics but utilizes a 20-TSSOP package instead of the 20-SO package. Pinout compatibility must be verified before substitution due to the physical package difference.