PIC18F2321T-I/ML - 8KB Flash 8-bit MCU, 28-QFN | Microchip
MPN: PIC18F2321T-I/ML ✓ Hoạt độngPIC18F2321T-I/ML Tóm tắt
A microcontroller (MCU) is a single-chip computer that combines a CPU, non-volatile program memory (Flash/ROM), volatile working memory (RAM), and programmable peripherals on one die. PIC microcontrollers from Microchip use a Harvard RISC architecture with a small, fixed instruction set (77 single-word instructions on this device) that simplifies software development, shortens interrupt latency, and yields deterministic execution. Within the broader taxonomy, the PIC18F2321 sits in the hierarchy: MCU -> 8-bit MCU -> PIC18 enhanced family -> nanoWatt power-managed variants. nanoWatt technology adds multiple low-power sleep modes that drop supply current to the microamp range, enabling battery-powered designs.
Key differentiating features of this device include 8 KB of self-programmable Flash (in-circuit serial programming via ICSP), 256 bytes of EEPROM data memory, an internal oscillator block, brown-out reset (BOR), a 10-bit ADC with 10 channels, dual analog comparators, a Capture/Compare/PWM (CCP) module, and nanoWatt sleep modes that typically idle below 1 uA. The PIC18 instruction set is backwards-compatible with PIC16 code while adding prioritized interrupts, hardware multiply, and an 8-bit-wide data path with 16-bit instruction words.
Architecturally, the PIC18F2321 uses a 14-bit instruction word fetched from Flash and executed by an 8-bit ALU in one instruction cycle (4 Fosc). The internal oscillator trims to +/-1% across voltage and temperature, removing the need for an external crystal in cost-sensitive applications. Peripherals map onto the same peripheral bus used across the PIC18F family, allowing easy code migration to the 40-pin (PIC18F4321) or 44-pin (PIC18F4520-class) siblings with little or no code change.
Typical applications include industrial sensor interfaces, low-cost motor control loops, small appliance controllers, USB-to-UART bridges when paired with a USB transceiver, consumer white goods, and battery-powered data loggers. The combination of nanoWatt modes and 10-bit ADC accuracy makes it well suited to portable instrumentation and remote sensor nodes.
When designing with this part, choose your oscillator source early - the internal RC oscillator saves BOM cost but is less accurate than an external crystal for timing-critical UART or USB communications. Always populate the ICSP connector footprint even in production designs, as it enables in-field firmware updates and simplifies prototype bring-up. This page synthesizes distributor pricing, drop-in package-matched alternatives, and practical design notes not found in the manufacturer datasheet.
Bộ thay thế dễ dàng lắp đặt cho PIC18F2321T-I/ML — cùng gói, chân-to-chân tương thích. Các bộ phận yêu cầu hàn PCB bị loại trừ.
Các biến thể trong loạt này
Các mẫu cùng loạt có thể lắp đặt dễ dàng tương thích với PIC18F2321T-I/ML (cùng hình factor và footprint) — khác nhau ở Package, Operating Temperature, Timers, ADC, Communication.
PIC18F2321-I/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18F2221T-I/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18F2420T-I/ML
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18F2520T-I/ML
✅ Drop-InLiên hệ để biết giá
Xem tài liệu →PIC18F23K22T-I/ML
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18F26K20T-I/ML
✅ Drop-In📋 Tham chiếu thay thế (không có trong danh mục)
PIC18F2321T-I/ML Tỷ lệ tối đa & tính chất điện
| Core Architecture | PIC18 (8-bit Harvard RISC) |
| Program Memory (Flash) | 8 KB (4K x 16 instructions) |
| Data Memory (RAM) | 512 bytes |
| Data EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Instruction Execution Time | 100 ns @ 40 MHz |
| Instruction Set Size | 77 single-word instructions |
| Operating Voltage (Vdd) | 2.0 V to 5.5 V |
| Digital I/O Pins | 25 |
| ADC | 10-bit, 10 channels |
| Communication Interfaces | 1x I2C, 1x SPI, 1x USART (Enhanced) |
| Analog Comparators | 2 |
| CCP Module | 1 (Capture/Compare/PWM) |
| Timers | 4 (Timer0/1/2/3) |
| Brown-Out Reset | Yes (BOR) |
| Internal Oscillator | Yes (31 kHz - 8 MHz, software selectable) |
| Khoảng nhiệt độ hoạt động | -40C to +85C (Industrial, 'I' suffix) |
| Hộp | 28-QFN (ML) 6x6 mm with Exposed Pad |
| Kiểu lắp đặt | Surface Mount |
| Cấp MSL | 1 (unlimited) |
| Trạng thái RoHS | Compliant |
| Lead-Free / Halogen-Free | Yes |
Cấu hình chân PIC18F2321T-I/ML
| Chân 1 | MCLR — Master Clear (reset) input, active low |
| Chân 2 | RA0/AN0 — PORTA bit 0 / ADC input channel 0 |
| Chân 3 | RA1/AN1 — PORTA bit 1 / ADC input channel 1 |
| Chân 4 | RA2/AN2/VREF- — PORTA bit 2 / ADC input channel 2 / ADC negative reference |
| Chân 5 | RA3/AN3/VREF+ — PORTA bit 3 / ADC input channel 3 / ADC positive reference |
| Chân 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Chân 7 | RA5/AN4/SS — PORTA bit 5 / ADC input channel 4 / SPI Slave Select |
| Chân 8 | VSS — Ground reference |
| Chân 9 | OSC1/RA7 — Oscillator input / PORTA bit 7 |
| Chân 10 | OSC2/RA6 — Oscillator output / PORTA bit 6 |
| Chân 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock |
| Chân 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Chân 13 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Chân 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Chân 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Chân 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Chân 17 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Chân 18 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Chân 19 | VSS — Ground reference |
| Chân 20 | VDD — Positive supply voltage |
| Chân 21 | RB0/INT0/AN12 — PORTB bit 0 / External interrupt 0 / ADC input channel 12 |
| Chân 22 | RB1/INT1/AN10 — PORTB bit 1 / External interrupt 1 / ADC input channel 10 |
| Chân 23 | RB2/INT2/AN8 — PORTB bit 2 / External interrupt 2 / ADC input channel 8 |
| Chân 24 | RB3/AN9/CCP2 — PORTB bit 3 / ADC input channel 9 / CCP2 |
| Chân 25 | RB4/AN11 — PORTB bit 4 / ADC input channel 11 |
| Chân 26 | RB5/AN13 — PORTB bit 5 / ADC input channel 13 |
| Chân 27 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Chân 28 | RB7/PGD — PORTB bit 7 / ICSP data |
| Chân 29 | EP — Exposed thermal pad - must be soldered to ground copper pour |
Ứng dụng tiêu biểu
PIC18F2321T-I/ML phù hợp cho 6 Áp dụngs: Industrial Sensor Interface Module, Low-Cost Motor Control Board, Battery-Powered Data Logger, Small Appliance Control Board, USB-to-UART Bridge Module, Consumer White Goods Remote Control.
Industrial Sensor Interface Module
The PIC18F2321T-I/ML is well suited to industrial sensor interface modules that aggregate analog and digital signals from factory equipment. Its 10-channel 10-bit ADC handles multiple sensor inputs (temperature via thermistor, pressure via strain gauge, flow via pulse, and 4-20 mA loopback), while the I2C bus talks to digital sensors such as accelerometers and EEPROMs. The USART links the module to a PLC or gateway, the Enhanced CCP module drives alarm or indicator PWM outputs, and brown-out reset protects against the voltage transients common on 24V industrial rails. The industrial -40C to +85C temperature range covers unheated cabinets and outdoor enclosures.
Được đề xuất
Low-Cost Motor Control Board
For brushed DC motor and small stepper control, the PIC18F2321T-I/ML delivers enough MIPS to run closed-loop PID without external DSP. The Enhanced CCP module generates 20 kHz PWM at 10-bit resolution for H-bridge drive signals, the analog comparators implement cycle-by-cycle current limiting without ADC intervention, and the 10-bit ADC reads back tacho-generator voltage for speed regulation. The 77 single-word instruction set keeps the PID loop deterministic, while nanoWatt sleep modes allow battery-backed idle when the motor is stopped. This combination delivers a fully featured BLDC or stepper controller for fans, pumps, and small appliances at sub-$3 BOM.
Được đề xuất
Battery-Powered Data Logger
The PIC18F2321T-I/ML excels in battery-powered data loggers where sleep-mode current is critical. nanoWatt technology drops quiescent current below 1 uA in sleep mode, allowing years of operation from a single CR2032 cell when wake-ups are infrequent. The 256-byte EEPROM buffers calibration and metadata, while 8 KB Flash stores the application plus a small FAT library. The 10-bit ADC samples battery voltage and analog sensors every few seconds, the I2C bus interfaces to a real-time clock and external flash, and the internal oscillator eliminates the external crystal cost and quiescent current. Industrial -40C to +85C operation handles outdoor and automotive deployments.
Được đề xuất
Small Appliance Control Board
Coffee machines, toaster ovens, washing machines, and other small appliances use the PIC18F2321T-I/ML as their primary control MCU. It reads user inputs from buttons and rotary encoders via the 10-bit ADC, drives triac-gated heater elements through the CCP PWM module, monitors NTC thermistors for closed-loop temperature control, and provides buzzer and LED feedback through GPIO. The internal oscillator and 28-QFN package enable a tiny 30x30 mm PCB, while the -40C to +85C industrial grade handles the thermal environment of a toaster or oven chassis. ICSP allows the appliance maker to update firmware in-line during production.
Được đề xuất
USB-to-UART Bridge Module
When paired with a USB-to-UART bridge IC such as the MCP2200 or MCP2221, the PIC18F2321T-I/ML forms a configurable USB peripheral that exposes its USART and GPIO to a host PC. This architecture is common in legacy firmware-flashing jigs, test fixtures, and field-service tools. The PIC18F2321 acts as the application-side processor while the USB IC handles enumeration and protocol translation; the PIC18F2321 also handles ICSP emulation, fault logging, and 10-bit ADC monitoring of test points. The 28-QFN allows the entire bridge module to fit in a USB connector shell.
Được đề xuất
Consumer White Goods Remote Control
Remote controls for ceiling fans, garage doors, and motorized blinds use the PIC18F2321T-I/ML for keypad scanning, IR or RF transmit, and battery monitoring. nanoWatt sleep draws sub-microamp current so the AAA battery lasts years; the 10-bit ADC monitors battery voltage and ambient light for adaptive backlight control; the USART or MSSP drives a 433 MHz ASK/FSK transmitter module. The 77 single-word instruction set simplifies deterministic IR protocol encoding, and the internal oscillator eliminates external crystal cost in a price-sensitive consumer market.
Được đề xuất
Tóm tắt các sản phẩm được đề xuất
Dữ liệu tham khảo kỹ thuật cho PIC18F2321T-I/ML — so sánh, hướng dẫn thiết kế và thông tin tuân thủ.
Hướng dẫn chọn lựa
So sánh với các sản phẩm thay thế
| Tham số | Sản phẩm này | PIC18F2321-I/ML | PIC18F2221T-I/ML | PIC18F2420T-I/ML | PIC18F23K22T-I/ML |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-QFN (ML) 6x6 mm | 28-QFN (ML) 6x6 mm - same | 28-QFN (ML) 6x6 mm - same | 28-QFN (ML) 6x6 mm - same | 28-QFN (ML) 6x6 mm - same |
| Program Memory (Flash) | 8 KB | 8 KB | 4 KB | 16 KB | 8 KB |
| RAM | 512 bytes | 512 bytes | 256 bytes | 768 bytes | 512 bytes |
| EEPROM | 256 bytes | 256 bytes | 128 bytes | 256 bytes | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 64 MHz (16 MIPS) |
| ADC | 10-bit, 10 channels | 10-bit, 10 channels | 10-bit, 10 channels | 10-bit, 11 channels | 10-bit, 14 channels |
| Operating Temperature Range | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Communication Interfaces | 1x I2C, 1x SPI, 1x USART | 1x I2C, 1x SPI, 1x USART | 1x I2C, 1x SPI, 1x USART | 1x I2C, 1x SPI, 1x USART | 2x I2C, 1x SPI, 1x USART |
| Internal Oscillator | Yes | Yes | Yes | Yes | Yes (XLP nanoWatt) |
Bảo phân biệt quan trọng
- Larger Flash memory than the older PIC18F2221 (vsPIC18F2221T-I/ML)
- Mature, low-cost family with broadest tool support (vsNewer PIC18F23K22)
- Pin compatibility with the entire PIC18F2xxx family (vsPIC18F14K50)
Ghi chú thiết kế
The 28-QFN package has a large center exposed thermal pad (EP) that must be soldered to a ground copper pour for electrical and thermal performance. Place at least 6 thermal vias (0.3 mm drill, 0.6 mm pad) in the EP landing area to sink heat into inner ground planes. Keep high-speed traces (USART, SPI clock) away from the analog AVdd/VREF pins to minimize crosstalk.
Decouple VDD with a 100 nF ceramic capacitor placed within 5 mm of the supply pin, and add a bulk 10 uF tantalum or aluminum electrolytic if switching loads are present. The PIC18F2321 supports an AVdd pin for clean ADC supply - if the application has digital and analog loads, isolate AVdd with a ferrite bead and 10 uF + 100 nF local decoupling. Brown-out reset (BOR) should be enabled in configuration bits to protect against the voltage sags that occur during motor inrush.
Do not confuse PIC18F2321 (28-pin) with PIC18F4321 (40-pin) - the additional pins expose extra I/O and peripherals not available on the 28-pin device. Also note that the 'T' suffix denotes Tape & Reel, not a temperature grade; 'I' = Industrial -40C to +85C, 'E' = Extended -40C to +125C. Programming via ICSP requires a 4-wire header (MCLR/VPP, PGD, PGC, VSS) - leave this footprint on the PCB for in-field firmware updates.
When using the internal oscillator at 8 MHz for UART communications, baud rate error can exceed 2 percent at high bitrates, which causes framing errors on remote devices. For reliable UART above 38400 baud, switch to a 10 MHz or 20 MHz external crystal. The PIC18F2321 supports primary oscillator modes HS, XT, and LP via the configuration bits - consult the family datasheet's oscillator section for capacitor selection guidelines.
Thông tin tuân thủ
RoHS compliant and lead-free per Microchip PIC18F2321 product page. Not AEC-Q100 qualified; for automotive applications, Microchip recommends PIC18F2xK22 family which carries AEC-Q100 Grade 1 (-40C to +125C) qualification.
