MCP795B22T-I/ST Equivalent & Substitute Parts

Part Overview

The MCP795B22T-I/ST is a Real Time Clock (RTC) IC with Clock/Calendar functionality, SPI interface, and 64B memory capacity. This device is classified as Obsolete, making equivalent and substitute parts necessary for new designs and production continuity. The part provides timekeeping with alarm, EEPROM, leap year support, square wave output, SRAM, unique ID, and watchdog timer functionality across a supply voltage range of 1.8V to 5.5V and operating temperature range of -40°C to 85°C.

Substiute Parts

MCP795B22T-I/ST

Microchip TechnologyIn Stock: 905MCP795B22T-I/ST Datasheet

Current PartRFQ

AB-RTCMC-32.768KHZ-ZIZE-S2-T

Abracon LLCIn Stock: 2110AB-RTCMC-32.768KHZ-ZIZE-S2-T Datasheet

MFR RecommendedRFQ

DS1391U-18+

Analog Devices Inc./Maxim IntegratedIn Stock: 976DS1391U-18+ Datasheet

MFR RecommendedRFQ

DS1394U-33+T&R

Analog Devices Inc./Maxim IntegratedIn Stock: 11330DS1394U-33+T&R Datasheet

MFR RecommendedRFQ

PCF2123TS/1,118

NXP USA Inc.In Stock: 2045PCF2123TS/1,118 Datasheet

MFR RecommendedRFQ

RX-4803LC:AA3 PURE SN

EPSONIn Stock: 849RX-4803LC:AA3 PURE SN Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution for the MCP795B22T-I/ST is determined by the following critical parameters:

• Interface Type: SPI (required match)
• Operating Temperature Range: -40°C to 85°C (required match)
• RoHS Compliance: ROHS3 Compliant (required match)
• Core Features: Alarm, Leap Year, Square Wave Output, Watchdog Timer (required match)
• Time/Date Format Support: HH:MM:SS and YY-MM-DD-dd (required match)
• Supply Voltage Compatibility: Overlap with 1.8V ~ 5.5V range
• Package Compatibility: 14-TSSOP form factor preferred for direct replacement; alternative packages acceptable if electrical parameters align

The substitute parts listed below meet these criteria and are classified as Active products, providing production continuity for the obsolete MCP795B22T-I/ST.

Parameter Comparison

Engineering Selection Recommendations

PCF2123TS/1,118 (NXP USA Inc.) is the primary substitute for direct replacement. This part shares the identical 14-TSSOP package form factor, matching pin configuration requirements. It maintains SPI interface compatibility, supports 12/24-hour time format and YY-MM-DD-dd date format, and operates across -40°C to 85°C. The supply voltage range of 1.6V to 5.5V overlaps with the original specification. Current consumption is significantly lower at 0.33µA to 0.38µA compared to 1µA, providing improved power efficiency. The part is Active status with ROHS3 compliance.

AB-RTCMC-32.768KHZ-ZIZE-S2-T (Abracon LLC) is a module-based alternative offering the lowest timekeeping current at 0.35µA to 0.4µA. This part requires PCB layout modifications due to its 10-SMD Module package but provides superior power efficiency and extended supply voltage range down to 1.1V. Active status and ROHS3 compliance are confirmed.

DS1391U-18+ and DS1394U-33+T&R (Analog Devices Inc./Maxim Integrated) are pin-compatible alternatives in 10-TFSOP/10-MSOP packages. DS1391U-18+ operates at 1.71V to 1.89V supply voltage with 100µA timekeeping current. DS1394U-33+T&R operates at 2.97V to 5.5V with 175µA timekeeping current. Both include trickle-charger functionality and are Active status with ROHS3 compliance. Package changes require PCB redesign.

RX-4803LC:AA3 PURE SN (EPSON) operates in 12-TFSOJ package with 24-hour time format only (no 12-hour option). Timekeeping current ranges from 2.1µA to 3.4µA. This part is suitable for applications where 24-hour format is acceptable and package miniaturization is prioritized. Active status and ROHS3 compliance are confirmed.

Frequently Asked Questions (FAQ)

Q: Can PCF2123TS/1,118 be used as a direct drop-in replacement for MCP795B22T-I/ST?

A: PCF2123TS/1,118 shares the identical 14-TSSOP package and pin configuration, making it suitable for direct PCB replacement without layout modifications. Both parts support SPI interface, 12/24-hour time format, YY-MM-DD-dd date format, alarm, leap year, square wave output, and watchdog timer functions. Operating temperature range and RoHS compliance match. Firmware verification is required to confirm register-level compatibility.

Q: What are the power consumption differences between substitute parts?

A: Timekeeping current varies significantly: PCF2123TS/1,118 and AB-RTCMC-32.768KHZ-ZIZE-S2-T consume 0.33µA to 0.4µA; RX-4803LC:AA3 PURE SN consumes 2.1µA to 3.4µA; DS1391U-18+ consumes 100µA; DS1394U-33+T&R consumes 175µA. Selection depends on battery-backed timekeeping duration requirements and system power budget constraints.

Q: Are package changes required for any substitutes?

A: PCF2123TS/1,118 maintains the original 14-TSSOP package, requiring no PCB modifications. AB-RTCMC-32.768KHZ-ZIZE-S2-T uses 10-SMD Module packaging; DS1391U-18+ and DS1394U-33+T&R use 10-TFSOP/10-MSOP packaging; RX-4803LC:AA3 PURE SN uses 12-TFSOJ packaging. Alternative packages require PCB layout redesign and footprint changes.

Q: Which substitute supports the widest supply voltage range?

A: AB-RTCMC-32.768KHZ-ZIZE-S2-T supports 1.1V to 5.5V, the widest range among all substitutes. This enables operation in ultra-low-power applications and systems with variable supply voltages.

Q: Do all substitutes support both 12-hour and 24-hour time formats?

A: PCF2123TS/1,118, AB-RTCMC-32.768KHZ-ZIZE-S2-T, DS1391U-18+, and DS1394U-33+T&R support 12/24-hour formats. RX-4803LC:AA3 PURE SN supports 24-hour format only. Application requirements determine format compatibility.

Q: What compliance certifications are common across all parts?

A: All listed substitutes are ROHS3 compliant and rated for -40°C to 85°C operating temperature. All maintain SPI interface compatibility and support YY-MM-DD-dd date format with alarm and leap year functionality.