Microchip Technology AT89S
AT89S variants from Microchip Technology
AT89S Overview
What changes between part numbers, and what to check before you lock the BOM — Microcontrollers.
AT89S is a Microchip Technology order-code family — not a single orderable MPN. This page lists 3 variants that share the same core device but differ in suffix fields (package, grade, reel/tube, electrical bin, etc.). Pick the exact full part number; substituting within the family without checking the datasheet often causes assembly or spec mismatches.
IC MCU 8BIT 4KB FLASH 44PLCC Other listed variants describe: IC MCU 8BIT 8KB FLASH 44TQFP; IC MCU 8BIT 8KB FLASH 40DIP.
Suffix examples in this family: 51-24JU, 52-24AU, 52-24PU. The characters after the base number usually encode package, temperature, or performance grade — compare the variant table column-by-column rather than assuming pin-compatible drops-in.
Example MPNs: AT89S51-24JU, AT89S52-24AU, AT89S52-24PU.
Key Features
- Lifecycle mix: ActiveConfirm lifecycle on the exact MPN, not just the base number prefix.
- 3 distinct suffix patternsExamples: 51-24JU, 52-24AU, 52-24PU. Decode suffix meaning in the ordering notes under the variant table.
Target Applications
- Microcontrollers — design-in and field replacement
- BOM scrub where only the base prefix is known but suffix is TBD
- Second-source checks when the original MPN is constrained
Ordering Variants
Compare 3 AT89S part numbers by package, electrical parameters, lifecycle, and availability. Use RFQ for stock and lead-time confirmation.
| Part Number | Description | Manufacturer | Lifecycle | RoHS | Availability | Action |
|---|---|---|---|---|---|---|
| AT89S51-24JU | IC MCU 8BIT 4KB FLASH 44PLCC | Microchip Technology | Active | Compliant | In Stock | |
| AT89S52-24AU | IC MCU 8BIT 8KB FLASH 44TQFP | Microchip Technology | Active | Compliant | In Stock | |
| AT89S52-24PU | IC MCU 8BIT 8KB FLASH 40DIP | Microchip Technology | Active | Compliant | In Stock |
Ordering Code Differences
How suffixes on AT89S map to package, grade, and reel options.
AT89S uses a shared prefix; characters after the prefix encode orderable options. Two lines with the same prefix are not drop-in replacements unless the differing columns match your need.
Suffixes seen here: 51-24JU, 52-24AU, 52-24PU.
Full MPN examples: AT89S51-24JU, AT89S52-24AU, AT89S52-24PU.
Tip: photograph or copy the reel label — reel diameter, QTY per reel, and moisture sensitivity level (MSL) are often suffix-driven and won't show in the schematic.
How to Choose the Right AT89S Microcontrollers
Match the footprint first
Pull the exact package drawing for your MPN — base-number swaps fail most often at the footprint, not the schematic.
Electrical headroom
Compare voltage and current columns in the variant table. For AT89S, a suffix with lower voltage or current rating will not survive the same circuit without recalculation.
Temp grade letter matters
Commercial (0–70 °C) and industrial (−40–85 °C+) suffixes look similar in the prefix — confirm ambient + self-heating, not just the first page of the datasheet.
Copy the full MPN
Do not BOM only "AT89S" — include the full suffix (e.g. 51-24JU, 52-24AU, 52-24PU). RFQ with reel/tube preference and required date code.
Technical Specifications
Core parameters for AT89S product family
Identity
Variant Parameters
Source AT89S with Octatronics
Request stock confirmation, lead time, date code, and pricing for all 3 ordering variants from Microchip Technology. Our team supports active, EOL, and hard-to-find component sourcing.
- Original manufacturer parts with traceability options
- BOM upload and multi-line RFQ support
- Package, grade, and compliance verification
Frequently Asked Questions
Common technical questions about the AT89S product family.