PIC16C55A-04I/SO Microchip Integrated Circuit (Small Outline Packages) In Stock
The PIC16C55A-04I/SO is an 8-bit PIC16 microcontroller from Microchip with EPROM-based program memory, operating at up to 4 MHz from an SMT 28-pin SOIC package. Introduced in 1990, it offers a wide I/O port count for its size and is suited for legacy embedded control systems, prototyping boards, and industrial equipment requiring a proven, UV-erasable architecture.
- Manufacturer
- Microchip
- Package
- Small Outline Packages
- Pin Count
- 28
- Lifecycle
- NOT RECOMMENDED
- Datasheet
- PIC16C55A-04I/SO Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $2.3100(MOQ 81)
- Temp Range
- -40.0°C to 85.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of PIC16C55A-04I/SO?
- 8-bit PIC16 core operating at up to 4 MHz
- EPROM program memory enabling UV-erasable field reprogramming
- 28-pin SOIC-28 SMT package with wide I/O port availability
- No on-chip ADC, simplifying design for pure digital control tasks
- PIC16 CPU family with established development toolchain support
- Pb-free RoHS-compliant construction
What is PIC16C55A-04I/SO used for?
The PIC16C55A-04I/SO is used in legacy industrial controllers, relay sequencers, and appliance control boards where its UV-erasable EPROM allows iterative firmware development and field reprogramming without flash-based tooling. Its 28-pin SOIC footprint and mature PIC16 architecture make it a reliable choice for maintenance, repair, and obsolescence management of equipment originally designed in the 1990s and early 2000s.
What are the specifications of PIC16C55A-04I/SO?
| Pbfree Code | Yes |
| Manufacturer Package Code | SOIC-28 |
| Factory Lead Time | 13Weeks |
| Date Of Intro | 1990-01-01 |
| YTEOL | 3 |
| Has ADC | NO |
| Bit Size | 8 |
| Boundary Scan | NO |
| CPU Family | PIC16 |
| Clock Frequency-Max | 4MHz |
| DAC Channels | NO |
| DMA Channels | NO |
| Format | FIXED POINT |
| Integrated Cache | NO |
| JESD-30 Code | R-PDSO-G28 |
| JESD-609 Code | e3 |
| Low Power Mode | YES |
| Number of I/O Lines | 20 |
| Number of Timers | 1 |
| On Chip Data RAM Width | 8 |
| On Chip Program ROM Width | 12 |
| PWM Channels | NO |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | SOP28,.4 |
| Package Shape | RECTANGULAR |
| Package Style | SMALL OUTLINE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| RAM (bytes) | 24 |
| RAM (words) | 24 |
| ROM (words) | 512 |
| ROM Programmability | OTPROM |
| Speed | 4MHz |
| Supply Current-Max | 3.3mA |
| Supply Voltage-Max | 5.5V |
| Supply Voltage-Min | 5V |
| Supply Voltage-Nom | 5V |
| Surface Mount | YES |
| Technology | CMOS |
| Temperature Grade | INDUSTRIAL |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| uPs/uCs/Peripheral ICs Type | MICROCONTROLLER, RISC |
| Package | Small Outline Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 1 |
| ECCN | EAR99 |
| HTS Code | 8542.31.00.01 |
| Country of Origin | Thailand |
Where can I find the PIC16C55A-04I/SO datasheet?
PIC16C55A-04I/SO Datasheet DownloadOfficial datasheet from Microchip
What are equivalent replacements for PIC16C55A-04I/SO?
Compatible alternatives and drop-in replacements for PIC16C55A-04I/SO:
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDIP28
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDSO28
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDSO28
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDIP28
Frequently Asked Questions
Why would a designer choose EPROM-based program storage in the PIC16C55A-04I/SO rather than a flash-based PIC16 successor?
EPROM memory allows the PIC16C55A-04I/SO to be UV-erased and reprogrammed multiple times, which was advantageous for prototyping and small production runs before in-circuit serial programming became universal. Legacy field-service operations for equipment designed around this 4 MHz 8-bit device also benefit from EPROM's long data-retention characteristics and the ability to verify erased state before reprogramming, supporting maintenance on 20-to-30-year-old industrial installations.
How does the 4 MHz maximum clock frequency of the PIC16C55A-04I/SO compare with modern PIC16 replacements, and does it affect processing throughput?
At 4 MHz with a single-cycle instruction architecture, the PIC16C55A-04I/SO executes up to 1 million instructions per second (1 MIPS). Modern PIC16F successors run at up to 32 MHz, delivering 8 times the throughput. For legacy maintenance, the 4 MHz limit is usually adequate for simple I/O sequencing and relay logic, but new designs with tighter timing or communication requirements should migrate to a current-generation PIC16F or PIC18 device.
What procurement challenges should buyers anticipate for the PIC16C55A-04I/SO given its end-of-life status?
With only 3 years estimated to end of life and a factory lead time of 13 weeks, the PIC16C55A-04I/SO is approaching discontinuation. Buyers supporting legacy equipment should place last-time-buy orders promptly and consider authorized distribution channels for guaranteed authenticity, as grey-market counterfeit risk increases for aging EPROM-based devices. Alternatively, evaluating a pin-compatible or functionally equivalent modern flash-based PIC16F microcontroller can eliminate supply risk while reducing migration effort.
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| Qty. | Unit Price | Ext. Price |
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| 81+ | $2.7900 | $225.99 |
| 100+ | $2.5400 | $254.00 |
| 1000+ | $2.4000 | $2400.00 |
| 5000+ | $2.3100 | $11550.00 |
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