PIC18F4321-I/PT Microchip Integrated Circuit (Quad Flat Packages) In Stock
Microchip PIC18F4321 is an 8-bit microcontroller with 8 KB Flash memory and 40 MHz clock, housed in a TQFP-44 package. It features a 10-bit ADC, UART, SPI, and I2C interfaces for versatile embedded control. Available from stock worldwide with RoHS-compliant lead-free construction.
- Manufacturer
- Microchip
- Package
- Quad Flat Packages
- Pin Count
- 44
- Lifecycle
- ACTIVE
- Datasheet
- PIC18F4321-I/PT Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $3.1800(MOQ 1)
- 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 PIC18 CPU core running up to 40 MHz for real-time control tasks
- 8 KB Flash program memory with 10-bit ADC for precision analog signal acquisition
- TQFP-44 package with UART/SPI/I2C interfaces enabling compact multi-protocol embedded designs
Applications
The PIC18F4321-I/PT suits industrial automation panels, home appliance control boards, and sensor data acquisition systems. Its integrated ADC and multi-protocol serial interfaces make it a strong fit for HVAC controllers, motor speed regulation, and low-power embedded nodes.
Specifications
| Pbfree Code | Yes |
| Manufacturer Package Code | TQFP-44 |
| Factory Lead Time | 6Weeks |
| YTEOL | 8 |
| Has ADC | YES |
| Bit Size | 8 |
| Boundary Scan | NO |
| CPU Family | PIC18 |
| Clock Frequency-Max | 40MHz |
| DAC Channels | NO |
| DMA Channels | NO |
| Format | FIXED POINT |
| Integrated Cache | NO |
| JESD-30 Code | S-PQFP-G44 |
| JESD-609 Code | e3 |
| Low Power Mode | YES |
| Number of External Interrupts | 3 |
| Number of I/O Lines | 36 |
| Number of Serial I/Os | 1 |
| Number of Timers | 6 |
| On Chip Program ROM Width | 8 |
| PWM Channels | YES |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | TQFP44,.39SQ,31 |
| Package Shape | SQUARE |
| Package Style | FLATPACK, THIN PROFILE |
| Peak Reflow Temperature (Cel) | 260 |
| Qualification Status | Not Qualified |
| RAM (bytes) | 512 |
| ROM (words) | 8192 |
| ROM Programmability | FLASH |
| Screening Level | TS 16949 |
| Speed | 40MHz |
| Supply Current-Max | 23mA |
| Supply Voltage-Max | 5.5V |
| Supply Voltage-Min | 4.2V |
| Supply Voltage-Nom | 5V |
| Surface Mount | YES |
| Technology | CMOS |
| Temperature Grade | INDUSTRIAL |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | GULL WING |
| Terminal Pitch | 0.8mm |
| Terminal Position | QUAD |
| Time@Peak Reflow Temperature-Max (s) | 40 |
| uPs/uCs/Peripheral ICs Type | MICROCONTROLLER, RISC |
| Package | Quad Flat Packages |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| Moisture Sensitivity Level | MSL 3 |
| ECCN | 3A991.A.2 |
| HTS Code | 8542.31.00.01 |
| Country of Origin | Philippines, Thailand |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for PIC18F4321-I/PT:
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
RISC Microcontroller, 8-Bit, FLASH, PIC18 CPU, 40MHz, CMOS, PQFP44
Frequently Asked Questions
What is the maximum clock frequency of PIC18F4321-I/PT and how does it affect real-time control loop timing?
The PIC18F4321-I/PT operates at up to 40 MHz, allowing instruction execution at 10 MIPS. This clock rate supports control loops with cycle times as short as 25 ns per instruction, making it suitable for fast PWM generation and real-time motor control tasks.
Which serial communication interfaces does PIC18F4321-I/PT support for connecting sensors and peripherals?
The device integrates USART, SPI, and I2C interfaces. USART supports baud rates up to 1 Mbps, SPI runs up to 10 MHz, and I2C operates at 100 kHz or 400 kHz, enabling connectivity to a wide range of sensors, EEPROMs, and display modules.
When should a designer choose PIC18F4321-I/PT over a smaller PIC16 device for an 8-bit embedded project?
Choose PIC18F4321-I/PT when the application requires more than 8 KB Flash, a 10-bit ADC with multiple channels, or higher throughput at 40 MHz. Its PIC18 architecture also provides a 16-level hardware stack and larger register file, reducing firmware complexity in interrupt-driven designs with 8 or more I/O lines.
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| Qty. | Unit Price | Ext. Price |
|---|---|---|
| 1+ | $3.9384 | $3.94 |
| 100+ | $3.6200 | $362.00 |
| 1000+ | $3.3400 | $3340.00 |
| 5000+ | $3.1800 | $15900.00 |
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