DS1501YS+

Real Time Clock Overview

The DS1501YS+ is a Y2K-compliant real-time clock/calendar with a parallel interface and 256 bytes of NV SRAM. It operates at +5V (4.5V to 5.5V) within an industrial temperature range of -40°C to +85°C. The device features BCD-coded timekeeping, automatic leap-year compensation, a programmable watchdog timer, and power-fail detection. It includes battery backup switching via VBAT and VBAUX inputs, ensuring data retention during power loss.

Real Time Clock Feature Summary

• Y2K-Compliant RTC with Century Register and Automatic Leap-Year Compensation
• 256 Bytes Battery-Backed NV SRAM with Parallel Interface
• Programmable Watchdog Timer and Time-of-Day Alarm
• +5V Operation (-40°C to +85°C Industrial Temperature Range)

Real Time Clock Applications

• Remote Systems
• Battery-Backed Systems
• Telecom Switches

Real Time Clock Procurement Notes

Verify the specific suffix 'YS' against official documentation, as standard listings typically specify 'WE' or 'WEN'. Confirm lead-free status and RoHS compliance for the exact manufacturing revision. Check for availability constraints or limited supply statuses associated with this specific package variant.

Real Time Clock Selection Notes

Select the DS1501YS+ for applications requiring a dedicated +5V parallel RTC with integrated NV SRAM. Ensure the system design accommodates the 28-pin SOIC package and provides appropriate pull-up resistors for open-drain outputs like IRQ, PWR, and RST. Verify crystal load capacitance requirements (6pF or 12.5pF) match the selected quartz component.

Real Time Clock Part Context

The DS1501 series belongs to Maxim Integrated's family of Y2K-compliant real-time clocks. It serves as a standalone solution for timekeeping and non-volatile memory in embedded systems. The 'Y' designation indicates +5V operation, distinguishing it from the 'W' series which supports +3.3V logic levels.

Real Time Clock Replacement Considerations

DS1501WE+ offers identical functionality with +3.3V operation instead of +5V. DS1501WEN+ provides the same features but covers the extended industrial temperature range of -40°C to +85°C. Cross-reference pinouts and voltage tolerances before substitution.