AT89S4051-24PU Microchip Integrated Circuit (Dual-In-Line Packages) In Stock

The AT89S4051-24PU is an 8-bit 8051-architecture microcontroller running up to 24 MHz with 4 kB of in-system programmable Flash and 256 B of RAM. It integrates two 16-bit timers, a full-duplex UART, and 15 programmable I/O lines in a compact 20-pin PDIP package. Available from stock worldwide with fast shipping.

OBSOLETEIntegrated CircuitVerified Jun 2026
Package / Visual Reference
AT89S4051-24PUDual-In-Line Packages
Quick Facts
Manufacturer
Microchip
Package
Dual-In-Line Packages
Pin Count
20
Lifecycle
OBSOLETE
Category
Integrated Circuit
Temp Range
-40.0°C to 85.0°C
RoHS
Compliant
Lead Time
3–7 business days
Shipping
DHL Express · Worldwide

Key Features

  • 8-bit 8051 core running at up to 24 MHz for reliable low-power embedded control
  • 4 kB in-system programmable Flash with 1,000-cycle endurance for flexible field updates
  • Compact 20-pin PDIP package with 15 programmable I/O lines, dual 16-bit timers, and full-duplex UART

Applications

The AT89S4051-24PU suits cost-sensitive embedded designs such as industrial sensor interfaces, home appliance controllers, and simple robotics that need a proven 8051 core. Its 4 kB Flash and 256 B RAM support small firmware footprints, while the integrated UART enables straightforward serial communication with host systems. The 20-pin PDIP form factor makes it easy to prototype on breadboards and migrate to low-volume production.

Specifications

Pbfree CodeYes
Factory Lead Time4Weeks
YTEOL0
Has ADCNO
Bit Size8
Boundary ScanNO
CPU Family8051
Clock Frequency-Max24MHz
DAC ChannelsNO
DMA ChannelsNO
FormatFIXED POINT
Integrated CacheNO
JESD-30 CodeR-PDIP-T20
JESD-609 Codee3
Low Power ModeYES
Number of External Interrupts2
Number of I/O Lines15
Number of Serial I/Os1
Number of Timers2
On Chip Data RAM Width8
On Chip Program ROM Width8
PWM ChannelsYES
Package Body MaterialPLASTIC/EPOXY
Package Equivalence CodeDIP20,.3
Package ShapeRECTANGULAR
Package StyleIN-LINE
Qualification StatusNot Qualified
RAM (bytes)256
ROM (words)4096
ROM ProgrammabilityFLASH
Speed24MHz
Supply Current-Max10.5mA
Supply Voltage-Max5.5V
Supply Voltage-Min3V
Supply Voltage-Nom3V
Surface MountNO
TechnologyCMOS
Temperature GradeINDUSTRIAL
Terminal FinishMATTE TIN
Terminal FormTHROUGH-HOLE
Terminal Pitch2.54mm
Terminal PositionDUAL
uPs/uCs/Peripheral ICs TypeMICROCONTROLLER
PackageDual-In-Line Packages

Compliance & Regulatory

RoHS StatusCompliant
Lead-FreeYes (Pb-Free)
Moisture Sensitivity LevelMSL 1
ECCNEAR99
HTS Code8542.31.00.01
Country of OriginThailand

Datasheet

AT89S4051-24PU Datasheet Download

Official datasheet from Microchip

Alternate & Equivalent Parts

No known alternates. Submit an RFQ and our team can suggest alternatives.

Frequently Asked Questions

What is the maximum clock frequency of the AT89S4051-24PU and how does it affect execution speed?

The AT89S4051-24PU operates at up to 24 MHz. In classic 8051 mode each instruction takes 12 clock cycles, yielding a peak throughput of 2 million instructions per second, which is sufficient for most low-speed sensor-reading and control loops in industrial or consumer applications.

How much non-volatile program storage does the AT89S4051-24PU provide, and can it be updated in the field?

It includes 4 kB of in-system programmable Flash memory with a guaranteed endurance of 1,000 write/erase cycles. Field updates are possible via the SPI-compatible ISP interface, requiring only 4 pins, so the device can be reprogrammed on a target board without removal.

Which compact embedded designs benefit most from the AT89S4051-24PU's 20-pin PDIP package?

The 20-pin PDIP package provides 15 I/O lines in a through-hole footprint measuring roughly 25.4 mm × 6.4 mm, making it ideal for small industrial controllers, keypad scanners, LED drivers, and home-appliance timer circuits where board space is limited and hand-soldering is preferred during prototyping.

What are the supply voltage limits for the AT89S4051-24PU, and is it compatible with 3.3 V systems?

The AT89S4051-24PU is specified for a VCC range of 2.7 V to 5.5 V, covering both 3.3 V and 5 V logic rails. At 2.7 V the maximum clock drops to 6 MHz, while the full 24 MHz is available from 4.5 V to 5.5 V, giving designers flexibility to optimize between speed and power.

Why Buy from FindMyChip

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Competitive Pricing
Factory-direct from China distributors, low MOQ
Fast Shipping
DHL Express 3–5 days · FedEx/UPS 5–7 days worldwide
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About Microchip

Microchip is a leading electronic component manufacturer. FindMyChip sources Microchip ICs directly from authorized China distributors, offering competitive pricing and reliable stock.

AvailabilityIn Stock
Reference Price (USD)
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In Stock · 24h Response · Worldwide Shipping

Lead Time3-7 business days
MOQFrom 1 piece
ShippingDHL / FedEx / UPS
OriginChina (Authorized)

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Thomas Mueller
Hardware Lead, SensorTech GmbH, Germany