AB0811-T3 Real Time Clock IC Equivalent & Substitute Parts

Part Overview

The AB0811-T3 is a Real Time Clock (RTC) IC with Clock/Calendar functionality manufactured by Abracon LLC, featuring SPI interface in a 16-VFQFN Exposed Pad package. This device provides timekeeping with alarm capability, leap year support, and trickle-charger functionality across a 1.7V to 3.6V supply range with ultra-low timekeeping current of 0.17µA to 0.22µA at 1.8V to 3V.

The AB0811-T3 is classified as Obsolete. Identifying equivalent and substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support ongoing production requirements. Substitute parts must maintain electrical compatibility across supply voltage, interface protocol, timekeeping accuracy, and operating temperature specifications while accommodating package and feature variations.

Substiute Parts

AB0811-T3

Abracon LLCIn Stock: 1176AB0811-T3 Datasheet

Current PartRFQ

AB0815-T3

Abracon LLCIn Stock: 127337AB0815-T3 Datasheet

DirectRFQ

M41T93ZMY6F

STMicroelectronicsIn Stock: 2469M41T93ZMY6F Datasheet

MFR RecommendedRFQ

MCP79520T-I/MS

Microchip TechnologyIn Stock: 1637MCP79520T-I/MS Datasheet

MFR RecommendedRFQ

MCP79521-I/MS

Microchip TechnologyIn Stock: 3319MCP79521-I/MS Datasheet

MFR RecommendedRFQ

MCP79521T-I/MS

Microchip TechnologyIn Stock: 3558MCP79521T-I/MS Datasheet

MFR RecommendedRFQ

MCP795W12T-I/ST

Microchip TechnologyIn Stock: 1085MCP795W12T-I/ST Datasheet

MFR RecommendedRFQ

MCP795W21-I/SL

Microchip TechnologyIn Stock: 1194MCP795W21-I/SL Datasheet

MFR RecommendedRFQ

MCP795W21T-I/ST

Microchip TechnologyIn Stock: 877MCP795W21T-I/ST Datasheet

MFR RecommendedRFQ

RX-4803LC:UCB PURE SN

EPSONIn Stock: 733RX-4803LC:UCB PURE SN Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitute parts for the AB0811-T3 are selected based on the following critical parameters that determine functional compatibility:

Primary Compatibility Criteria:

• Interface Protocol: SPI (mandatory match)
• Operating Temperature Range: -40°C ~ 85°C (mandatory match)
• Supply Voltage Range: Minimum 1.7V support required
• Time/Date Format: HH:MM:SS:hh and YY-MM-DD-dd (mandatory match)
• RoHS3 Compliance: Required for regulatory alignment
• Moisture Sensitivity Level: MSL 1 preferred for handling consistency

Secondary Considerations:

• Package form factor (QFN, SOIC, TSSOP, MSOP variations acceptable with PCB redesign)
• Memory size and additional features (SRAM, EEPROM, Watchdog Timer) represent functional enhancements
• Timekeeping current specifications (lower is preferable for battery-backed applications)
• Mounting type (all substitutes are Surface Mount compatible)

Substitutes are grouped into three categories: direct package equivalents, alternative package options with enhanced features, and functionally compatible alternatives from different manufacturers.

Parameter Comparison

Engineering Selection Recommendations

Tier 1 - Direct Replacement (Recommended):

AB0815-T3 from Abracon LLC is the primary substitute. This part maintains identical electrical specifications, package form factor (16-VFQFN Exposed Pad), and interface protocol. The AB0815-T3 is in Active product status with high inventory availability (127,301 units), ensuring long-term supply continuity. Enhanced features include 256B SRAM, Watchdog Timer, and Leap Year support. ROHS3 compliance and MSL 1 rating match the original specification. No PCB redesign is required.

Tier 2 - Microchip Technology MCP795 Series (Package Redesign Required):

The MCP79520T-I/MS, MCP79521-I/MS, MCP79521T-I/MS, MCP795W12T-I/ST, MCP795W21-I/SL, and MCP795W21T-I/ST represent functionally compatible alternatives from Microchip Technology. All maintain SPI interface, -40°C to 85°C operating range, and YY-MM-DD-dd date format. Supply voltage range is 1.8V to 3.6V (minimum 1.8V versus 1.7V for AB0811-T3). These parts feature enhanced memory (64B SRAM/EEPROM), Unique ID, and Watchdog Timer functionality. Package variations (10-MSOP, 14-TSSOP, 14-SOIC) require PCB layout modifications. All parts are Active status with adequate inventory. ROHS3 compliant.

Tier 3 - Alternative Manufacturers (Significant Redesign):

M41T93ZMY6F (STMicroelectronics) and RX-4803LC:UCB PURE SN (EPSON) provide SPI-based RTC functionality with -40°C to 85°C operation. M41T93ZMY6F operates at 2.38V to 5.5V with integrated crystal in 18-SOX package, requiring substantial PCB redesign. RX-4803LC:UCB operates at 1.6V to 5.5V in 12-TFSOJ package. Both are Active status with ROHS3 compliance. These options are suitable only when package constraints or extended voltage range requirements justify redesign effort.

Compliance Verification:

All substitute parts maintain ROHS3 compliance, MSL 1 rating, and REACH Unaffected or REACH Affected status consistent with the original AB0811-T3. EAR99 export classification applies uniformly across all options.

Frequently Asked Questions (FAQ)

Q: Can I use AB0815-T3 as a direct drop-in replacement for AB0811-T3?

A: Yes. AB0815-T3 is the recommended substitute. Both parts share identical package (16-VFQFN Exposed Pad), electrical specifications (1.7V to 3.6V supply, SPI interface, -40°C to 85°C operation), and time/date formats. AB0815-T3 is in Active status with superior inventory availability. The only difference is enhanced features (256B SRAM, Watchdog Timer) which are backward compatible.

Q: What is the minimum supply voltage requirement for Microchip MCP795 series substitutes?

A: Microchip MCP795 series parts (MCP79520, MCP79521, MCP795W12, MCP795W21) operate at 1.8V to 3.6V supply range. This represents a 0.1V higher minimum compared to AB0811-T3 (1.7V minimum). Designs operating below 1.8V require verification against actual circuit requirements before substitution.

Q: Do package changes affect SPI communication protocol?

A: No. All substitute parts use identical SPI interface protocol. Package changes (QFN to MSOP, TSSOP, or SOIC) affect only PCB layout and footprint design. Firmware and software interfaces remain unchanged. Pin-to-pin signal mapping must be verified against individual datasheets during layout redesign.

Q: Which substitute offers the lowest timekeeping current consumption?

A: AB0815-T3 and AB0811-T3 both specify 0.17µA to 0.22µA at 1.8V to 3V. Microchip MCP795 series specifies 1µA at 1.8V to 3.6V. EPSON RX-4803LC specifies 2.1µA to 3.4µA at 3V to 5V. For battery-backed applications requiring ultra-low power, Abracon parts (AB0815-T3 or AB0811-T3) provide superior efficiency.

Q: Are all substitutes ROHS3 compliant?

A: Yes. All listed substitute parts maintain ROHS3 compliance status matching the original AB0811-T3 specification. Moisture Sensitivity Level 1 (Unlimited) applies uniformly across all options, ensuring consistent handling and storage requirements.

Q: What is the inventory status of recommended substitutes?

A: AB0815-T3 has 127,301 units in stock. Microchip MCP795 series parts range from 852 to 3,459 units depending on packaging variant. M41T93ZMY6F has 2,385 units. RX-4803LC:UCB has 666 units. AB0815-T3 provides the highest inventory security for sustained production requirements.