PIC18F4320-E/PT - 8KB Flash MCU 40MHz 36 I/O TQFP-44 | Microchip
MPN: PIC18F4320-E/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.45 | $7.45 |
| 10 | $6.91 | $69.10 |
| 100 | $6.12 | $612.00 |
| 500 | $5.43 | $2,715.00 |
| 1,000 | $4.85 | $4,850.00 |
| 3,000 | $4.2 | $12,600.00 |
PIC18F4320-E/PT Overview
What is a PIC18 Flash microcontroller? PIC18F-series devices are 8-bit CMOS RISC microcontrollers from Microchip Technology built around an enhanced Harvard architecture with separate program and data buses. They sit in the broader taxonomy microcontroller -> embedded processor -> semiconductor IC, and are widely adopted in cost-sensitive embedded designs because of their deterministic instruction timing, low power nanoWatt Technology, and rich peripheral integration.
Key features include 13 channels of 10-bit Analog-to-Digital conversion, two analog comparators, two Capture/Compare/PWM modules, a synchronous serial port configurable as either 3-wire SPI or 2-wire I2C, an Enhanced Universal Synchronous Asynchronous Receiver Transmitter (EUSART), and an in-circuit debugger (ICD) interface. Operating voltage spans 4.2 V to 5.5 V across the extended -40C to +125C industrial temperature range, suitable for industrial and automotive-grade environments.
The architecture combines a 16-bit instruction word with an 8-bit data path, providing 77 single-word instructions and C-compiler-friendly addressing modes. Self-programming capability enables field firmware updates, while the ICD interface simplifies in-system debug. nanoWatt Technology provides ultra-low-power sleep modes (<100 nA typical) for battery-backed designs.
Typical applications include industrial control systems, HVAC sensor interfaces, automotive body controllers, consumer appliance controllers, and USB-to-serial bridges when paired with the PIC18F2550/4550 family. The 36 I/O lines comfortably drive keypad scanning, character LCDs, and multi-drop RS-485 nodes.
When designing with the PIC18F4320-E/PT, ensure the 5 V rail is regulated within 4.2 V to 5.5 V to prevent Flash programming failures, place decoupling capacitors within 5 mm of each VDD/VSS pair, and use Microchip's MPLAB X IDE with MPLAB XC8 compiler for firmware development.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design guidance compiled from the Microchip datasheet, DigiKey inventory, and Mouser listings as of 2026-09-27.
Drop-in alternatives for PIC18F4320-E/PT — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with PIC18F4320-E/PT (same form factor and footprint) — differing in Package, Program Memory (Flash), ADC, Mounting Type, Data SRAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F4320-I/PT
✅ Drop-In✓ In Stock
$3.62 / Unit
View Datasheet →PIC18F4320-E/P
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC18F4520-I/PT
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →PIC18F46K80-I/PT
✅ Drop-In✓ In Stock
$4.21 / Unit
View Datasheet →PIC18F4420-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F2580-I/SP
✅ Drop-In✓ In Stock
$4.55 / Unit
View Datasheet →PIC18F4320-E/PT Maximum Ratings & Electrical Characteristics
| Family | PIC18Fxxxx |
| Core | 8-bit PIC RISC (Harvard) |
| Program Memory (Flash) | 8 KB |
| SRAM | 512 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Supply Voltage (Vdd) | 4.2 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, 13 channels |
| Comparators | 2 |
| CCP Modules | 2 |
| Serial Interfaces | SPI / I2C (MSSP), EUSART |
| Package | 44-pin TQFP (PT), 10x10 mm |
| Operating Temperature Range | -40C to +125C (Extended, -E suffix) |
| In-Circuit Debug | Yes (ICD) |
| Self-Programming | Yes |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
PIC18F4320-E/PT Pin Configuration
| Pin 1 | RA2/AN2/VREF- — PORTA bit 2 / ADC input 2 / negative voltage reference |
| Pin 2 | RA3/AN3/VREF+ — PORTA bit 3 / ADC input 3 / positive voltage reference |
| Pin 3 | RA4/T0CKI/C1OUT — PORTA bit 4 / Timer0 clock input / Comparator 1 output |
| Pin 4 | RA5/AN4/SS/LVDIN — PORTA bit 5 / ADC input 4 / SPI slave select / LVD input |
| Pin 5 | RE0/RD/AN5 — PORTE bit 0 / read control / ADC input 5 |
| Pin 6 | RE1/WR/AN6 — PORTE bit 1 / write control / ADC input 6 |
| Pin 7 | RE2/CS/AN7 — PORTE bit 2 / chip select / ADC input 7 |
| Pin 8 | VDD — Positive supply voltage |
| Pin 9 | VSS — Ground |
| Pin 10 | RB0/INT0/FLT0 — PORTB bit 0 / external interrupt 0 / PWM fault input |
| Pin 11 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 12 | RB2/INT2/CANTX — PORTB bit 2 / external interrupt 2 (CAN TX on F2480/F2580) |
| Pin 13 | RB3/INT3/CANRX — PORTB bit 3 / external interrupt 3 (CAN RX on F2480/F2580) |
| Pin 14 | RB4/KBI0 — PORTB bit 4 / keyboard interrupt 0 |
| Pin 15 | RB5/KBI1/PGM — PORTB bit 5 / keyboard interrupt 1 / LVP programming |
| Pin 16 | RB6/KBI2/PGC — PORTB bit 6 / keyboard interrupt 2 / ICSP clock |
| Pin 17 | RB7/KBI3/PGD — PORTB bit 7 / keyboard interrupt 3 / ICSP data |
| Pin 18 | VSS — Ground |
| Pin 19 | VDD — Positive supply voltage |
| Pin 20 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 21 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 module |
| Pin 22 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Pin 23 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 24 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 25 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 26 | RC6/TX/CK — PORTC bit 6 / EUSART transmit / clock |
| Pin 27 | RC7/RX/DT — PORTC bit 7 / EUSART receive / data |
| Pin 28 | VSS — Ground |
| Pin 29 | VDD — Positive supply voltage |
| Pin 30 | OSC1/CLKI/RA7 — Crystal oscillator input / external clock in / PORTA bit 7 |
| Pin 31 | OSC2/CLKO/RA6 — Crystal oscillator output / clock out / PORTA bit 6 |
| Pin 32 | VSS — Ground |
| Pin 33 | VDD — Positive supply voltage |
| Pin 34 | RD0/PSP0 — PORTD bit 0 / parallel slave port bit 0 |
| Pin 35 | RD1/PSP1 — PORTD bit 1 / parallel slave port bit 1 |
| Pin 36 | RD2/PSP2 — PORTD bit 2 / parallel slave port bit 2 |
| Pin 37 | RD3/PSP3 — PORTD bit 3 / parallel slave port bit 3 |
| Pin 38 | RD4/PSP4 — PORTD bit 4 / parallel slave port bit 4 |
| Pin 39 | RD5/PSP5 — PORTD bit 5 / parallel slave port bit 5 |
| Pin 40 | RD6/PSP6 — PORTD bit 6 / parallel slave port bit 6 |
| Pin 41 | RD7/PSP7 — PORTD bit 7 / parallel slave port bit 7 |
| Pin 42 | VSS — Ground |
| Pin 43 | VDD — Positive supply voltage |
| Pin 44 | RA0/AN0 — PORTA bit 0 / ADC input 0 |
| Pin 45 | RA1/AN1 — PORTA bit 1 / ADC input 1 |
Typical Applications
PIC18F4320-E/PT is suitable for 6 applications: Industrial Control and Sensor Hub, HVAC Climate Controller, Automotive Body Electronics, Consumer Appliance Control Board, USB-to-Serial Bridge Dongle, Battery-Powered Sensor Node.
Industrial Control and Sensor Hub
The PIC18F4320-E/PT fits industrial sensor-hub controllers by integrating 13 channels of 10-bit ADC and 36 I/O lines into a 44-pin TQFP, eliminating external multiplexer ICs. Its 40 MHz core executes deterministic control loops with 100 ns instruction timing, while the extended -40C to +125C temperature range tolerates factory-floor thermal stress. Used with a 4.2-5.5 V regulated supply, the MCU scans thermocouples, RTDs, and 4-20 mA current loops at 10 ksps aggregate rate, communicating results via the EUSART to a PLC over RS-485.
Recommended
HVAC Climate Controller
The PIC18F4320-E/PT is well suited for HVAC wall thermostats and zone controllers where its 10-bit ADC reads thermistor temperature sensors and two analog comparators detect over-temperature conditions without a separate supervisor IC. Two CCP PWM modules drive variable-speed blower fans, while nanoWatt Technology sleep currents below 100 nA extend battery life in wireless models. The 8 KB Flash holds scheduling logic for 7-day programmable setpoints and firmware upgrade over UART.
Recommended
Automotive Body Electronics
In automotive body controllers the PIC18F4320-E/PT's extended -40C to +125C operating range handles under-hood thermal cycles per AEC-Q100 stress profiles, though formal AEC-grade qualification requires the PIC18F46K80-I/PT variant. Its EUSART drives LIN-bus master nodes via a TJA1027 transceiver, while CCP PWMs dim interior lighting and run window lift motors. 8 KB Flash stores door-zone state machine logic for lock/unlock sequencing with 256-byte EEPROM retaining user preferences through battery disconnect.
Recommended
Consumer Appliance Control Board
Washing machines, microwaves, and induction cooktops use the PIC18F4320-E/PT to drive user-keypad scanning, character-LCD displays, and triac-fired heater elements. The MSSP peripheral runs an SPI master bus to digital potentiometers that adjust cooking-power profiles, while the EUSART communicates with the inverter board via opto-isolated RS-485. Mechanical endurance of appliance relays is monitored via interrupts on RB0-RB3, with 256-byte EEPROM logging fault codes for service diagnostics.
Recommended
USB-to-Serial Bridge Dongle
Though the PIC18F4320-E/PT itself lacks a USB peripheral, it pairs with the PIC18F2550 or PIC18F4550 in companion dongles to provide isolated serial translation between legacy RS-232 equipment and USB hosts. The PIC18F4320-E/PT then interprets the UART stream, performs protocol conversion, and forwards commands to downstream motor or sensor nodes, leveraging its 40 MHz throughput and 36 I/O lines as a flexible bridge SoC.
Recommended
Battery-Powered Sensor Node
The PIC18F4320-E/PT with nanoWatt Technology supports <100 nA sleep current and 1.8 microA RTCC operation, enabling multi-year battery life on a 2xAA cell pack in remote sensor telemetry nodes. The internal EEPROM stores calibration coefficients, while the MSSP wakes the host sensor over I2C to take measurements at scheduled intervals. The EUSART transmits aggregated data bursts via a low-power sub-GHz radio module, then returns to sleep between samples.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4320-E/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4320-I/PT | PIC18F4520-I/PT | PIC18F46K80-I/PT | PIC18F4420-I/PT | PIC18F2580-I/SP |
|---|---|---|---|---|---|---|
| Package | TQFP-44 (PT) | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 8 KB | 32 KB | 64 KB | 16 KB | 32 KB |
| SRAM | 512 bytes | 512 bytes | 1536 bytes | 3.6 KB | 768 bytes | 1.5 KB |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 1 KB | 256 bytes | 256 bytes |
| ADC Channels | 13 | 13 | 13 | 11 (12-bit) | 13 | 8 |
| Operating Temperature | -40C to +125C (Extended) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) | -40C to +85C (Industrial) |
| CAN Peripheral | No | No | No | Yes (CAN) | No | Yes (CAN) |
Key Differentiators
- Extended temperature grade to +125C (vs PIC18F4320-I/PT)
- Code-compatible upgrade path to 32 KB Flash (vs PIC18F4520-I/PT)
- CAN-bus enabled variant available in same footprint (vs PIC18F2580-I/SP)
Design Notes
The PIC18F4320-E/PT requires a regulated 4.2 V to 5.5 V supply. Place a 100 nF ceramic decoupling capacitor within 5 mm of each VDD/VSS pin pair (pins 8/9, 18/19, 28/29, 32/33, 42/43). Add a bulk 10 uF tantalum or aluminum-polymer capacitor near the IC to handle ADC reference load transients during conversion bursts. Brown-out reset should be programmed to ensure Flash programming integrity.
Estimated: a 2-layer FR4 board with a continuous ground plane directly beneath the TQFP-44 footprint provides adequate thermal dissipation and reduces EMI emission from the 40 MHz oscillator. For TQFP packages, route all signal traces on the top layer and stitch 4 vias around the exposed paddle substitute area at 0.8 mm pitch, matching JEDEC MS-026 land pattern recommendations. The ICD PGC/PGD lines (RB6/RB7) should be kept short and isolated from switching nodes.
Do not connect the ICSP PGC/PGD pins to heavily loaded driver outputs - this prevents in-circuit debugging and programming failures. Configuration bits must be set to enable the correct oscillator mode (HS for >10 MHz crystal, XT for 1-10 MHz, RC for cost-sensitive low-pin-count designs). The LVP (Low-Voltage Programming) bit should be disabled in production to free up RB5 as a general-purpose GPIO. Always clear the WDT (watchdog timer) in long-running loops to prevent unintended resets.
Compliance Information
TQFP-44 (PT) is RoHS compliant and lead-free per Microchip material declaration. Not formally AEC-Q100 qualified - select PIC18F46K80-I/PT or PIC18F4620-I/PT for automotive designs requiring AEC-Q100.