AT89LP51RB2-20PU Equivalent & Substitute Parts

Part Overview

The AT89LP51RB2-20PU is an 8-bit microcontroller from Microchip Technology's 89LP series, featuring 24KB of FLASH program memory and operating at 20MHz. This device is actively produced and widely used in embedded applications requiring low-power 8051-compatible processing. Substitute parts may be necessary due to inventory constraints, design optimization requirements, or application-specific memory capacity needs.

Substiute Parts

AT89LP51RB2-20PU

Microchip TechnologyIn Stock: 2095AT89LP51RB2-20PU Datasheet

Current PartRFQ

AT89LP51RD2-20PU

Microchip TechnologyIn Stock: 3503AT89LP51RD2-20PU Datasheet

DirectRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution eligibility for the AT89LP51RB2-20PU is determined by the following critical parameters:

• Manufacturer & Series: Must be Microchip Technology 89LP series to ensure architectural compatibility with the 8051 core
• Core Processor & Size: Must maintain 8051 core and 8-bit architecture
• Operating Speed: Must support 20MHz operation
• Package & Pinout: Must use 40-DIP package with identical pin configuration (37 I/O pins)
• Voltage Supply Range: Must support 2.4V ~ 5.5V operating range
• Connectivity & Peripherals: Must include EBI/EMI, I2C, SPI, UART/USART and Brown-out Detect/Reset, POR, PWM, WDT
• Data Converters: Must include A/D 7x10b
• Operating Temperature: Must support -40°C ~ 85°C range
• Compliance: Must maintain ROHS3 compliance and REACH Unaffected status

The AT89LP51RD2-20PU qualifies as a direct substitute based on these parameters. The primary difference is increased program memory capacity (64KB vs. 24KB) and corresponding RAM expansion (2.25K x 8 vs. 1.375K x 8), which does not affect substitution eligibility when additional memory is acceptable or beneficial for the application.

Parameter Comparison

Engineering Selection Recommendations

Both the AT89LP51RB2-20PU and AT89LP51RD2-20PU maintain Active product status and full compliance with ROHS3 and REACH regulations. Selection between these parts should be based on application memory requirements:

• AT89LP51RB2-20PU: Select when 24KB program memory and 1.375K RAM are sufficient for the application
• AT89LP51RD2-20PU: Select when increased program memory (64KB) and expanded RAM (2.25K) are required or when inventory availability favors this variant

Both devices are suitable for production use with equivalent reliability and compliance profiles.

Frequently Asked Questions (FAQ)

Q: Can AT89LP51RD2-20PU replace AT89LP51RB2-20PU in existing designs?

A: Yes. The AT89LP51RD2-20PU is pin-compatible and functionally compatible. The primary difference is increased memory capacity. Designs utilizing less than 24KB program memory and 1.375K RAM will operate identically with the substitute part.

Q: Are there any package differences between these parts?

A: No. Both parts use the 40-DIP (0.600", 15.24mm) package with identical pinout and 37 I/O pins. Through-hole mounting characteristics are equivalent.

Q: Do voltage supply requirements differ?

A: No. Both parts operate across the identical 2.4V ~ 5.5V supply range and maintain the same operating temperature specification of -40°C ~ 85°C.

Q: What connectivity interfaces are supported by both parts?

A: Both the AT89LP51RB2-20PU and AT89LP51RD2-20PU include EBI/EMI, I2C, SPI, and UART/USART connectivity, along with Brown-out Detect/Reset, POR, PWM, and WDT peripherals.

Q: Are both parts compliant with environmental regulations?

A: Yes. Both parts are ROHS3 Compliant and REACH Unaffected, meeting current environmental and regulatory requirements.