PIC18LF4320-I/P - 8KB Flash 8-bit MCU | Microchip Technology
MPN: PIC18LF4320-I/P ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.92 | $7.92 |
| 10 | $7.13 | $71.30 |
| 100 | $6.34 | $634.00 |
| 500 | $5.55 | $2,775.00 |
| 1,000 | $4.76 | $4,760.00 |
PIC18LF4320-I/P Overview
An 8-bit PIC microcontroller belongs to the family of modified Harvard-architecture microcontrollers, characterized by separate program and data memory buses, an instruction set optimized for single-cycle execution, and integrated peripherals such as ADC, timers, and communication interfaces. Within the broader semiconductor hierarchy, 8-bit MCUs sit below 16-bit and 32-bit MCUs in computational capability but excel in cost-sensitive, deterministic, low-power embedded applications such as appliance control, sensor interfacing, and industrial monitoring.
Key features of the PIC18LF4320-I/P include a 10-bit Analog-to-Digital Converter (ADC) with up to 13 input channels, 36 digital I/O pins, an Enhanced Capture/Compare/PWM (ECCP) module, two 8-bit timers plus three 16-bit timers, and multiple communication interfaces including USART, MSSP (SPI/I2C), and a parallel port. The nanoWatt technology provides multiple power-managed operating modes (Run, Idle, Sleep, and a secondary oscillator for real-time clock operation), enabling extended battery life in portable designs.
The device uses an enhanced PIC18 instruction set with 77 single-word instructions and a hardware 8x8 multiplier for efficient arithmetic operations. With self-programmable Flash memory, ICD (In-Circuit Debug) support, and a wide operating temperature range of -40C to +85C, it is engineered for both prototype and production environments.
Typical applications include industrial control panels, HVAC sensor modules, automotive accessory controllers, home appliance user interfaces, and low-power remote sensor nodes. Its 36 I/O capability supports multi-channel sensor aggregation, while the 10-bit ADC delivers adequate resolution for temperature, pressure, and voltage monitoring.
When designing with the PIC18LF4320-I/P, ensure decoupling capacitors are placed close to the VDD pins (typically 100 nF) and consider using MPLAB X IDE with compatible XC8 compilers and PICKit programmers for firmware development. The 40-pin PDIP footprint enables easy breadboarding and socket-based prototyping, while the wide voltage range simplifies integration into mixed-voltage systems.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone, providing an actionable reference for engineers evaluating this MCU for embedded designs.
Drop-in alternatives for PIC18LF4320-I/P — 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 PIC18LF4320-I/P (same form factor and footprint) — differing in Package, Timers, Operating Temperature, Core Architecture, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF4321-I/P
✅ Drop-In✓ In Stock
$4.98 / Unit
View Datasheet →PIC18F4320-I/P
✅ Drop-In✓ In Stock
$4.05 / Unit
View Datasheet →PIC18F4685-I/P
✅ Drop-In✓ In Stock
$5.4 / Unit
View Datasheet →PIC18F4520-I/P
✅ Drop-In✓ In Stock
$5.35 / Unit
View Datasheet →PIC18F2420-I/SP
✅ Drop-In✓ In Stock
$5.22 / Unit
View Datasheet →PIC18LF2220-I/SP
✅ Drop-In✓ In Stock
$2.18 / Unit
View Datasheet →PIC18LF4320-I/P Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Program Memory (Flash) | 8 KB |
| Data RAM | 512 bytes |
| Data EEPROM | 256 bytes |
| Operating Frequency | 0 to 40 MHz |
| Instruction Throughput | 10 MIPS |
| Operating Voltage Range | 2.0 V to 5.5 V |
| Number of I/O Pins | 36 |
| ADC | 10-bit, up to 13 channels |
| Timers | 2 x 8-bit, 3 x 16-bit |
| Communication Interfaces | 1 x USART, 1 x MSSP (SPI/I2C), PSP |
| Capture/Compare/PWM | 1 x ECCP, 1 x CCP |
| Instruction Set | 77 instructions, hardware 8x8 multiplier |
| Power-Saving Modes | Run, Idle, Sleep, Secondary Oscillator |
| Operating Temperature | -40 C to +85 C |
| Package | 40-pin PDIP (P) |
| Mounting Type | Through-Hole (DIP) |
| RoHS Status | Compliant (lead-free) |
PIC18LF4320-I/P Pin Configuration
| Pin 1 | MCLR — Reset input (active low) |
| Pin 2 | RA0 — Digital I/O / analog input AN0 |
| Pin 3 | RA1 — Digital I/O / analog input AN1 |
| Pin 4 | RA2 — Digital I/O / analog input AN2 / Vref- |
| Pin 5 | RA3 — Digital I/O / analog input AN3 / Vref+ |
| Pin 6 | RA4 — Digital I/O / analog input AN4 (open drain) |
| Pin 7 | RA5 — Digital I/O / analog input AN5 / SS |
| Pin 8 | RA6 — Digital I/O / oscillator output |
| Pin 9 | RA7 — Digital I/O / oscillator input |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply voltage (2.0V to 5.5V) |
| Pin 12 | RB0 — Digital I/O / interrupt-on-change |
| Pin 13 | RB1 — Digital I/O / interrupt-on-change |
| Pin 14 | RB2 — Digital I/O / interrupt-on-change |
| Pin 15 | RB3 — Digital I/O / interrupt-on-change |
| Pin 16 | RB4 — Digital I/O / interrupt-on-change |
| Pin 17 | RB5 — Digital I/O / interrupt-on-change |
| Pin 18 | RB6 — Digital I/O / PGC (ICSP clock) |
| Pin 19 | RB7 — Digital I/O / PGD (ICSP data) |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply voltage (2.0V to 5.5V) |
| Pin 22 | RC0 — Digital I/O / T1OSO / T1CKI |
| Pin 23 | RC1 — Digital I/O / T1OSI / CCP2 |
| Pin 24 | RC2 — Digital I/O / CCP1 / PWM1 |
| Pin 25 | RC3 — Digital I/O / SCL / SCK |
| Pin 26 | RC4 — Digital I/O / SDA / SDI |
| Pin 27 | RC5 — Digital I/O / SDO |
| Pin 28 | RC6 — Digital I/O / TX / CK |
| Pin 29 | RC7 — Digital I/O / RX / DT |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive supply voltage (2.0V to 5.5V) |
| Pin 32 | RD0 — Digital I/O / PSP data bit 0 |
| Pin 33 | RD1 — Digital I/O / PSP data bit 1 |
| Pin 34 | RD2 — Digital I/O / PSP data bit 2 |
| Pin 35 | RD3 — Digital I/O / PSP data bit 3 |
| Pin 36 | RD4 — Digital I/O / PSP data bit 4 |
| Pin 37 | RD5 — Digital I/O / PSP data bit 5 |
| Pin 38 | RD6 — Digital I/O / PSP data bit 6 |
| Pin 39 | RD7 — Digital I/O / PSP data bit 7 |
| Pin 40 | RE0 — Digital I/O / RD / AN6 |
| Pin 41 | RE1 — Digital I/O / WR / AN7 |
| Pin 42 | RE2 — Digital I/O / CS / AN8 |
| Pin 43 | RE3 — Digital I/O |
Typical Applications
PIC18LF4320-I/P is suitable for 6 applications: Industrial Sensor Monitoring, Home Appliance Control Boards, Low-Power Remote Sensor Nodes, Automotive Accessory Controllers, HVAC Thermostat Modules, Educational and Prototyping Platforms.
Industrial Sensor Monitoring
The PIC18LF4320-I/P fits industrial sensor monitoring applications due to its 10-bit ADC with up to 13 input channels and wide 2.0V to 5.5V supply range. Its 36 digital I/O pins support multi-channel sensor aggregation across temperature, pressure, and voltage signals. The nanoWatt power management modes reduce quiescent current for remote sensor nodes operating on battery power. With 8KB Flash and 512 bytes RAM, the MCU handles typical RTD/thermocouple linearization, digital filtering, and Modbus RTU communications on the integrated USART. The 40-pin PDIP package simplifies prototyping and field serviceability.
Recommended
Home Appliance Control Boards
The PIC18LF4320-I/P is well-suited for home appliance control boards such as washing machines, microwave ovens, and HVAC thermostats. Its 77-instruction PIC18 instruction set with hardware 8x8 multiplier executes control loops efficiently, while the ECCP module drives motor PWM signals at programmable frequencies. The 8KB Flash accommodates user-interface state machines, EEPROM stores user settings (timer presets, calibration data) across power cycles, and the wide voltage range supports both battery-backed and AC-line-derived supplies. The 40-pin PDIP package eases integration into appliance wiring harnesses.
Recommended
Low-Power Remote Sensor Nodes
The PIC18LF4320-I/P enables battery-powered remote sensor nodes through nanoWatt technology, providing Sleep mode currents below 1 microampere when idle. The integrated secondary oscillator supports a 32 kHz crystal for timekeeping and wake-up intervals without the main oscillator running. Its 2.0V to 5.5V operation accommodates single-cell Li-coin, two-cell AA alkaline, or 3.3V regulated supplies. The 10-bit ADC reads battery voltage and sensor data periodically before returning to sleep, achieving multi-year battery life in low-duty-cycle telemetry applications.
Recommended
Automotive Accessory Controllers
The PIC18LF4320-I/P powers automotive accessory controllers such as interior lighting, mirror adjusters, and seat heaters when used in the industrial -40C to +85C range. Its 36 I/O capability supports multi-channel LED/PWM outputs with the ECCP module, while the 8KB Flash accommodates driving algorithms and diagnostic logic. The wide voltage tolerance handles 12V automotive rails regulated to 5V, and the robust PIC18 architecture withstands ESD and load-dump transients typical in vehicle electrical environments. The 40-pin PDIP simplifies repair and replacement in service shops.
Recommended
HVAC Thermostat Modules
The PIC18LF4320-I/P fits HVAC thermostat designs with its 10-bit ADC reading NTC thermistors and potentiometers for setpoint adjustment. The 8KB Flash stores scheduling logic and LCD driving routines, while the integrated USART interfaces to WiFi/BLE modules for smart thermostat connectivity. Its wide operating temperature range supports indoor/outdoor HVAC environments, and the nanoWatt Sleep modes reduce standby power when the system is idle. The MSSP peripheral drives SPI/I2C sensors or expansion EEPROM for configuration storage.
Recommended
Educational and Prototyping Platforms
The PIC18LF4320-I/P is well-suited for educational microcontroller training and prototyping due to its 40-pin PDIP through-hole package, which fits standard breadboards and IC sockets. The 8KB Flash and 77-instruction set allow students to explore interrupts, timers, ADC, and communication peripherals without overwhelming complexity. MPLAB X IDE with XC8 compiler and PICKit 3/4 programmers provide a free, full-featured development environment. The wide voltage range and rugged PIC18 architecture tolerate common student wiring mistakes and power supply variations.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4320-I/P — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF4321-I/P | PIC18F4320-I/P | PIC18F4685-I/P | PIC18F4520-I/P | PIC18F2420-I/SP | PIC18LF2220-I/SP |
|---|---|---|---|---|---|---|---|
| Package | PDIP-40 | PDIP-40 - same | PDIP-40 - same | PDIP-40 - same | PDIP-40 - same | PDIP-28 - smaller | PDIP-28 - smaller |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 16 KB | 8 KB | 96 KB | 32 KB | 8 KB | 4 KB |
| RAM | 512 bytes | 768 bytes | 512 bytes | 3328 bytes | 1536 bytes | 512 bytes | 512 bytes |
| Operating Voltage | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 23 | 23 |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit |
| CAN Interface | No | No | No | Yes | No | No | No |
| Operating Temperature | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
Key Differentiators
- Wide 2.0V to 5.5V supply range with nanoWatt power management (vs PIC18F4320-I/P)
- Higher Flash memory density with identical pinout (vs PIC18LF4321-I/P)
- Mid-density 8KB Flash positioning in the PIC18 family (vs PIC18F4520-I/P)
- Lower cost and complexity versus CAN-equipped variants (vs PIC18F4685-I/P)
Design Notes
Place 100 nF decoupling capacitors close to each VDD pin (pins 11, 21, 31) and a single 10 uF bulk capacitor near the supply entry point. The PIC18LF4320-I/P operates from 2.0V to 5.5V; for 5V systems use an LDO such as MCP1700, and for 3.3V systems a low-dropout regulator is acceptable. The nanoWatt Sleep mode reduces supply current below 1 uA, but only when the A/D converter, USART, and main oscillator are disabled before entering Sleep.
The MCLR pin (pin 1) is active low and must be tied to VDD through a 10 kohm resistor for proper operation; failure to do so results in a continuous reset state. Do not connect any load to RA4 because it is an open-drain output and requires a pull-up resistor. Configuration bits (FOSC, WDTE, etc.) must be set in the source code pragma statements; leaving them at default may disable the oscillator or watchdog unexpectedly.
Use a 40-pin PDIP socket in development environments to allow easy firmware swap-out and IC replacement. Keep the analog inputs (RA0-RA5, RE0-RE3) traces short and away from switching digital signals (RC2 CCP1 PWM output, RC6/RC7 USART) to minimize ADC noise coupling. Provide a separate analog ground island under the ADC reference pins and connect it to the digital ground at a single point near the regulator to avoid ground loops.
Route the ICSP clock (RB6/PGC) and ICSP data (RB7/PGD) lines to a programming header connector with short traces; avoid passing these signals through vias or near noise sources. Place the 32.768 kHz secondary oscillator crystal close to RC0/RC1 (T1OSO/T1OSI) pins with load capacitors per crystal datasheet to ensure accurate timing for Sleep wake-up intervals.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified (industrial -40C to +85C only); use PIC18F4685 for automotive.
