AT89C4051-12PC Equivalent & Substitute Parts

Part Overview

The AT89C4051-12PC is an 8-bit microcontroller from Microchip Technology's 89C series, featuring 4KB of FLASH program memory, 128 bytes of RAM, and 15 I/O pins. Designed for embedded applications requiring low-cost 8051-compatible processing, this device operates at 12MHz with integrated UART/USART connectivity and brown-out detection.

The AT89C4051-12PC is classified as obsolete. Locating equivalent substitute parts is necessary to maintain design continuity, ensure supply chain availability, and support legacy system maintenance and production requirements.

Substiute Parts

AT89C4051-12PC

Microchip TechnologyIn Stock: 1278AT89C4051-12PC Datasheet

Current PartRFQ

AT89C4051-12PU

Microchip TechnologyIn Stock: 2023AT89C4051-12PU Datasheet

MFR RecommendedRFQ

Key Parameters

Substitute Part Grouping Explanation

Substitution of the AT89C4051-12PC is determined by strict equivalence across the following critical parameters:

Core processor architecture (8051), core size (8-bit), program memory capacity (4KB FLASH), RAM capacity (128 x 8), I/O count (15 pins), clock speed (12MHz), connectivity (UART/USART), and physical package (20-DIP). The substitute part AT89C4051-12PU maintains identical functional specifications and pinout compatibility.

Voltage supply range and operating temperature range are secondary parameters that may differ between the main part and substitutes, provided the substitute's range encompasses or exceeds the application requirements. Packaging format (tube vs. other) does not affect electrical or functional equivalence.

Parameter Comparison

Engineering Selection Recommendations

The AT89C4051-12PU is a direct functional equivalent to the AT89C4051-12PC. Both devices share identical core architecture, memory configuration, I/O capability, and pinout.

The AT89C4051-12PU offers an extended voltage supply range (2.7V ~ 6V versus 4V ~ 6V) and extended operating temperature range (-40°C ~ 85°C versus 0°C ~ 70°C), providing greater operational flexibility for applications with broader environmental or power supply requirements.

The AT89C4051-12PU carries ROHS3 compliance, whereas the AT89C4051-12PC is RoHS non-compliant. For applications subject to RoHS regulatory requirements, the AT89C4051-12PU is the appropriate selection.

Both parts maintain identical REACH and ECCN classifications. Selection between these parts should be based on compliance requirements, supply availability, and operating condition specifications of the target application.

Frequently Asked Questions (FAQ)

Q: Can AT89C4051-12PU replace AT89C4051-12PC in existing designs?

A: Yes. The AT89C4051-12PU is functionally equivalent. Both devices feature identical 8051 core architecture, 4KB FLASH memory, 128 bytes RAM, 15 I/O pins, 12MHz clock speed, and 20-DIP package. Pinout and electrical interface are identical. No design modification is required.

Q: What are the differences between AT89C4051-12PC and AT89C4051-12PU?

A: The primary differences are voltage supply range (AT89C4051-12PU: 2.7V ~ 6V; AT89C4051-12PC: 4V ~ 6V), operating temperature range (AT89C4051-12PU: -40°C ~ 85°C; AT89C4051-12PC: 0°C ~ 70°C), and RoHS compliance status (AT89C4051-12PU: ROHS3 Compliant; AT89C4051-12PC: RoHS non-compliant). Functional specifications and pinout are identical.

Q: Does packaging format affect substitution compatibility?

A: No. Packaging format (tube, tray, or other) does not affect electrical or functional equivalence. Both AT89C4051-12PC and AT89C4051-12PU are supplied in 20-DIP through-hole packages with identical physical dimensions and pinout.

Q: Are there any firmware or software compatibility concerns when substituting these parts?

A: No. Both devices are 8051-compatible microcontrollers with identical instruction set architecture, memory organization, and peripheral interface. Firmware developed for AT89C4051-12PC executes without modification on AT89C4051-12PU.

Q: Which part should be selected for new designs?

A: For new designs, AT89C4051-12PU is recommended. It provides extended operating ranges, ROHS3 compliance, and improved availability compared to the obsolete AT89C4051-12PC.