T89C51RB2-SLSIM Equivalent & Substitute Parts

Part Overview

The T89C51RB2-SLSIM is an 8-bit microcontroller from Microchip Technology based on the 80C51 core architecture. This device integrates 16KB of FLASH program memory, 1.25KB of RAM, and 32 I/O pins in a 44-PLCC surface mount package. The part operates at 40MHz with a supply voltage range of 4.5V to 5.5V and includes integrated peripherals such as SPI, UART/USART, Power-On Reset (POR), Pulse Width Modulation (PWM), and Watchdog Timer (WDT).

The T89C51RB2-SLSIM is classified as obsolete. Identifying equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support long-term product maintenance and production requirements.

Substiute Parts

T89C51RB2-SLSIM

Microchip TechnologyIn Stock: 900T89C51RB2-SLSIM Datasheet

Current PartRFQ

AT89C51RB2-SLSUM

Microchip TechnologyIn Stock: 3642AT89C51RB2-SLSUM Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the T89C51RB2-SLSIM is determined by strict equivalence across the following critical parameters:

• Core processor architecture (80C51)
• Core size (8-Bit)
• Program memory capacity and type (16KB FLASH)
• RAM capacity (1.25K x 8)
• I/O pin count (32)
• Connectivity interfaces (SPI, UART/USART)
• Integrated peripherals (POR, PWM, WDT)
• Package type and pinout (44-LCC J-Lead)
• Operating temperature range (-40°C ~ 85°C)

The AT89C51RB2-SLSUM qualifies as a direct substitute based on matching all core functional parameters. Differences in maximum operating speed (60MHz vs. 40MHz), supply voltage range (2.7V ~ 5.5V vs. 4.5V ~ 5.5V), product status (Active vs. Obsolete), and compliance certifications do not prevent functional substitution in applications designed for the original part.

Parameter Comparison

Engineering Selection Recommendations

The AT89C51RB2-SLSUM is the direct substitute for the obsolete T89C51RB2-SLSIM. Selection of this substitute is supported by the following factors:

• Active product status ensures ongoing availability and manufacturing support
• ROHS3 compliance aligns with current environmental and regulatory requirements, whereas the original part is RoHS non-compliant
• Identical core architecture, memory configuration, I/O count, and peripheral set guarantee functional compatibility
• Enhanced maximum operating speed (60MHz) and expanded supply voltage range (2.7V ~ 5.5V) provide operational flexibility
• Identical package geometry and pinout enable direct board-level replacement without layout modifications
• Both parts are manufactured by Microchip Technology, ensuring consistent design and quality standards

Frequently Asked Questions (FAQ)

Q: Can the AT89C51RB2-SLSUM be used as a direct replacement for the T89C51RB2-SLSIM?

A: Yes. Both parts share identical core processor architecture, memory capacity, I/O configuration, and package pinout. The substitute operates at a higher maximum speed and supports a wider supply voltage range, making it functionally compatible with designs specified for the original part.

Q: What are the key differences between these two parts?

A: The primary differences are product status (Active vs. Obsolete), RoHS compliance (ROHS3 vs. non-compliant), maximum operating speed (60MHz vs. 40MHz), supply voltage range (2.7V ~ 5.5V vs. 4.5V ~ 5.5V), and moisture sensitivity level (3 vs. 2). These differences do not affect functional substitution.

Q: Are the packages physically identical?

A: Yes. Both parts use the 44-PLCC (16.6x16.6) surface mount package with 44-LCC J-Lead configuration. Pin assignments and mechanical dimensions are identical, enabling direct board-level replacement.

Q: Does the higher speed rating of the substitute part affect compatibility?

A: No. The AT89C51RB2-SLSUM operates at a maximum of 60MHz, while the original part is rated for 40MHz. The substitute can operate at or below the original part's speed without functional degradation, making it backward compatible.

Q: What is the impact of the wider supply voltage range on the substitute?

A: The AT89C51RB2-SLSUM supports operation from 2.7V to 5.5V, compared to the original part's 4.5V to 5.5V range. This expanded range provides additional design flexibility and does not compromise compatibility with systems designed for the original 4.5V to 5.5V specification.

Q: Is RoHS compliance a factor in selecting the substitute?

A: The AT89C51RB2-SLSUM is ROHS3 compliant, while the original part is RoHS non-compliant. For applications subject to RoHS regulations or environmental requirements, the substitute is the appropriate choice.