PIC16C66-04/SO Microchip Integrated Circuit (Other) In Stock
Microchip PIC16C66-04/SO is an 8-bit PIC16 family OTP microcontroller operating at up to 4 MHz in a 28-pin SOIC package. Offers digital I/O without ADC in a 0.300-inch plastic SOIC-28 form factor introduced in 1993 for cost-sensitive embedded designs. Available from authorized distributors with worldwide shipping.
- Manufacturer
- Microchip
- Package
- Other
- Pin Count
- 28
- Lifecycle
- NOT RECOMMENDED
- Datasheet
- PIC16C66-04/SO Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $5.9700(MOQ 1)
- Temp Range
- ?°C to 70.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
What are the key features of PIC16C66-04/SO?
- 8-bit PIC16 architecture with up to 4 MHz clock frequency in a compact 28-pin SOIC-28 surface mount package
- OTP (One-Time Programmable) program memory for cost-effective production programming in volume manufacturing
- 28-pin digital I/O without ADC for simple control and communication tasks, reducing cost versus higher-integration variants
What is PIC16C66-04/SO used for?
PIC16C66-04/SO is used in legacy embedded control applications requiring simple digital I/O management such as relay control, keypad scanning, and serial communication interfacing in consumer appliances and industrial equipment. Its 4 MHz OTP architecture suits cost-sensitive volume production where firmware is finalized before manufacturing, eliminating the need for flash reprogramming capability. The 28-pin SOIC-28 package integrates into compact PCBs with automated SMT assembly.
What are the specifications of PIC16C66-04/SO?
| Pbfree Code | Yes |
| Manufacturer Package Code | SOIC-28 |
| Date Of Intro | 1993-07-01 |
| 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 External Interrupts | 1 |
| Number of I/O Lines | 22 |
| Number of Serial I/Os | 4 |
| Number of Timers | 5 |
| On Chip Data RAM Width | 8 |
| On Chip Program ROM Width | 14 |
| 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) | 368 |
| ROM (words) | 8192 |
| ROM Programmability | EPROM |
| Screening Level | TS 16949 |
| Speed | 4MHz |
| Supply Current-Max | 20mA |
| Supply Voltage-Max | 6V |
| Supply Voltage-Min | 4V |
| Supply Voltage-Nom | 5V |
| Surface Mount | YES |
| Technology | CMOS |
| Temperature Grade | COMMERCIAL |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 1.27mm |
| Terminal Position | DUAL |
| uPs/uCs/Peripheral ICs Type | MICROCONTROLLER, RISC |
| Package | Other |
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 PIC16C66-04/SO datasheet?
PIC16C66-04/SO Datasheet DownloadOfficial datasheet from Microchip
What are equivalent replacements for PIC16C66-04/SO?
Compatible alternatives and drop-in replacements for PIC16C66-04/SO:
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDIP28
RISC Microcontroller, 8-Bit, OTPROM, PIC16 CPU, 4MHz, CMOS, PDIP28
Frequently Asked Questions
What is the maximum operating clock frequency of the PIC16C66-04/SO, and what does the 04 suffix indicate?
The PIC16C66-04/SO operates at a maximum clock frequency of 4 MHz, which is indicated by the '04' speed suffix in the part number. At 4 MHz with the standard 4-cycle PIC16 instruction execution, the device achieves 1 million instructions per second (1 MIPS), which is adequate for simple control, relay switching, serial protocol handling, and basic digital I/O management in 8-bit embedded applications.
Does the PIC16C66-04/SO include an ADC, and what types of applications suit its all-digital I/O design?
No, the PIC16C66-04/SO does not include an ADC or DAC, making it a purely digital I/O microcontroller. This suits applications where only discrete digital signals are processed, such as relay control systems, UART or SPI communication handlers, keypad and switch matrix scanners, and LED or output latch drivers, where adding an ADC would unnecessarily increase cost for a design with no analog sensing requirements.
What memory type does the PIC16C66-04/SO use, and how does OTP affect production programming?
The PIC16C66-04/SO uses OTP (One-Time Programmable) program memory, meaning firmware can only be written once after manufacturing. For volume production builds where firmware is fully validated before PCB assembly, OTP devices offer a lower per-unit cost compared to flash variants. However, designers must ensure firmware is production-ready before committing, as OTP devices cannot be erased or reprogrammed after the initial write cycle.
How does the SOIC-28 package of the PIC16C66-04/SO compare to the DIP package for board layout?
The PIC16C66-04/SO's SOIC-28 (0.300-inch body width) surface mount package occupies approximately 70% less board area than an equivalent 28-pin DIP package. The 1.27 mm lead pitch of the SOIC-28 enables finer PCB routing between pins compared to the 2.54 mm DIP pitch, and compatibility with automated reflow soldering makes it preferred for modern production lines even in designs originating from the 1993-era PIC16C architecture.
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More from Microchip
| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $7.0400 | $7.04 |
| 4+ | $6.4379 | $25.75 |
| 8+ | $6.3450 | $50.76 |
| 16+ | $6.2521 | $100.03 |
| 1000+ | $6.2000 | $6200.00 |
| 5000+ | $5.9700 | $29850.00 |
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