PIC18LF4320T-I/ML - 8KB Flash 8-Bit MCU 44-VQFN | Microchip
MPN: PIC18LF4320T-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.27 | $7.27 |
| 10 | $6.54 | $65.40 |
| 100 | $5.82 | $582.00 |
| 500 | $5.21 | $2,605.00 |
| 1,000 | $4.68 | $4,680.00 |
PIC18LF4320T-I/ML Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory (Flash/ROM), data memory (RAM), and programmable peripherals. The PIC18F/LF family is Microchip's high-performance 8-bit architecture offering enhanced instruction set, C-friendly compiler support (MPLAB XC8), and nanoWatt Technology for dynamic power management. MCUs sit within the broader taxonomy of microprocessors -> computing ICs -> embedded processors -> microcontrollers, and dominate cost-sensitive, low-power embedded designs.
Key features include 36 digital I/O pins, a 10-bit ADC with up to 13 input channels, multiple serial interfaces (USART, MSSP for SPI/I2C), four timer modules, and nanoWatt power management modes. The 44-VQFN exposed pad package provides low thermal resistance for improved power dissipation in compact layouts, while the 8 KB flash supports typical mid-complexity embedded applications.
The architecture uses a 16-bit modified Harvard instruction set with an 8-bit data path, achieving up to 10 MIPS at 40 MHz. Internal PLL options allow flexible clocking from low-frequency crystals, and the device supports ICSP (In-Circuit Serial Programming) for field updates. Brown-out Reset, Power-on Reset, and a Watchdog Timer ensure reliable operation in industrial environments.
Typical applications include industrial sensor interfaces, HVAC controls, low-power remote sensing nodes, small appliance controllers, and consumer electronics requiring USB-free, USB-less connectivity. The 13-channel 10-bit ADC is well suited for analog sensor reading, while multiple PWM outputs enable motor or LED control tasks.
When designing with this device, ensure the exposed pad (EP) is soldered to a sufficiently large copper pour for thermal performance. The LF variant's low-voltage operation (down to 2.0 V) enables two-AA-battery or single Li-cell designs but does not support 5V-only analog performance of the F variant.
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet, supporting engineers searching for cross-reference, replacement, and integration guidance for the PIC18LF4320T-I/ML.
Drop-in alternatives for PIC18LF4320T-I/ML — 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 PIC18LF4320T-I/ML (same form factor and footprint) — differing in Package, Timers, Core, ADC, I/O Pins.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF4320-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4320-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4320T-I/PT
✅ Drop-In✓ In Stock
$4.15 / Unit
View Datasheet →PIC18LF4221-I/ML
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC18LF4220-I/ML
✅ Drop-In✓ In Stock
$4.61 / Unit
View Datasheet →PIC18LF4320-I/PT
✅ Drop-In✓ In Stock
$5.9 / Unit
View Datasheet →PIC18LF4320T-I/ML Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit (PIC18 enhanced) |
| Program Memory Size | 8 KB (4K x 16) Flash |
| Data RAM | 512 bytes |
| EEPROM Size | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Operating Voltage Range | 2.0 V to 5.5 V |
| I/O Pins | 36 |
| ADC | 10-bit, up to 13 channels |
| Package | 44-pin VQFN (ML) with Exposed Pad |
| Operating Temperature | -40C to +85C (Industrial) |
| Mounting Type | Surface Mount |
| Packaging | Tape & Reel |
| Timers | 4 (Timer0/1/2/3) |
| Communication Interfaces | USART, MSSP (SPI/I2C) |
| RoHS Compliance | Compliant |
| Power-Saving Modes | nanoWatt Technology (Sleep, Idle) |
PIC18LF4320T-I/ML Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (Reset) input / Programming voltage / PORTE bit 3 |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input channel 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input channel 1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2 / Analog input 2 / ADC VREF- |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input 3 / ADC VREF+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI Slave Select |
| Pin 8 | RE0/RD/AN5 — PORTE bit 0 / Read signal / Analog input 5 |
| Pin 9 | RE1/WR/AN6 — PORTE bit 1 / Write signal / Analog input 6 |
| Pin 10 | RE2/CS/AN7 — PORTE bit 2 / Chip Select / Analog input 7 |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI/RA7 — Oscillator input / External clock / PORTA bit 7 |
| Pin 14 | OSC2/CLKO/RA6 — Oscillator output / Clock output / PORTA bit 6 |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator out / Timer1 clock |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 20 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 21 | RC6/TX/CK — PORTC bit 6 / USART transmit / USART clock |
| Pin 22 | RC7/RX/DT — PORTC bit 7 / USART receive / USART data |
| Pin 23 | RB0/AN12/INT0 — PORTB bit 0 / Analog input 12 / External interrupt 0 |
| Pin 24 | RB1/AN10/INT1 — PORTB bit 1 / Analog input 10 / External interrupt 1 |
| Pin 25 | RB2/AN8/INT2 — PORTB bit 2 / Analog input 8 / External interrupt 2 |
| Pin 26 | RB3/AN9/CCP2 — PORTB bit 3 / Analog input 9 / CCP2 |
| Pin 27 | RB4/AN11 — PORTB bit 4 / Analog input 11 |
| Pin 28 | RB5/PGM — PORTB bit 5 / LVP programming |
| Pin 29 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 30 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 31 | VDD — Positive supply voltage |
| Pin 32 | VSS — Ground reference |
| Pin 33 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Pin 34 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port bit 1 |
| Pin 35 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port bit 2 |
| Pin 36 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port bit 3 |
| Pin 37 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port bit 4 |
| Pin 38 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port bit 5 |
| Pin 39 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port bit 6 |
| Pin 40 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port bit 7 |
| Pin 41 | VDD — Positive supply voltage |
| Pin 42 | VSS — Ground reference |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18LF4320T-I/ML is suitable for 6 applications: Industrial Sensor Interface, HVAC Climate Control, Low-Power Remote Sensing Node, Small Appliance Controller, Automotive Accessory Module, USB-Free Consumer Electronics.
Industrial Sensor Interface
The PIC18LF4320T-I/ML is well-suited for industrial sensor interface modules requiring multi-channel analog acquisition. The integrated 13-channel 10-bit ADC provides direct connection to temperature, pressure, and flow sensors without external multiplexing. Its 2.0-5.5 V operating range accommodates both 3.3 V and 5 V transducer rails, while 36 GPIO pins handle multiple discrete sensor inputs and digital outputs. The -40C to +85C industrial temperature grade ensures reliable operation in factory-floor enclosures. nanoWatt Sleep mode drops quiescent current to nanoampere levels for battery-backed sensor nodes that wake periodically to log measurements.
Recommended
HVAC Climate Control
HVAC controller boards benefit from the PIC18LF4320T-I/ML's combination of 8 KB flash for control firmware, 13 ADC channels for thermistor and humidity sensor inputs, and PWM outputs for damper and fan motor control. The MSSP peripheral supports SPI or I2C communication with external display drivers and EEPROM. nanoWatt Idle and Sleep modes reduce energy waste during standby periods. The wide 2.0-5.5 V supply range allows direct operation from rectified 5 V wall-adapter rails or 24 VAC control circuits with simple rectification.
Recommended
Low-Power Remote Sensing Node
Battery-powered remote sensor nodes leverage the PIC18LF4320T-I/ML's LF low-voltage core operating down to 2.0 V, enabling direct connection to a single Li-ion cell or two AA batteries. nanoWatt Technology Sleep mode reduces quiescent current to under 100 nA, allowing multi-year battery life when the MCU wakes briefly to take ADC readings and transmit via UART. The 8 KB flash stores calibration coefficients and protocol stacks, while 512 bytes of RAM buffers sensor data. The exposed pad 44-VQFN package provides low thermal resistance for sustained operation in outdoor enclosures.
Recommended
Small Appliance Controller
Consumer small appliances such as coffee makers, blenders, and washing machines use the PIC18LF4320T-I/ML for user-interface management and motor control. Four timer modules generate PWM signals for variable-speed motor drives, while the USART interfaces with LCD or LED display drivers. 36 GPIO pins handle keypad scanning, status LEDs, and relay outputs. The 44-VQFN package fits compact appliance PCBs, and industrial -40C to +85C temperature tolerance handles kitchen and laundry room environments. Brown-out Reset and Watchdog Timer ensure reliable recovery from supply glitches.
Recommended
Automotive Accessory Module
The PIC18LF4320T-I/ML operates across the automotive 12 V nominal rail (regulated down to 5 V or 3.3 V) for accessory modules such as interior lighting controllers, seat-position memories, and aftermarket gauge clusters. Its 13-channel ADC reads multiple potentiometers and analog sensors simultaneously. The Watchdog Timer and Brown-out Reset ensure reliable recovery from automotive load-dump transients. Note that for AEC-Q100 qualified automotive designs, Microchip recommends the PIC18F series with the -I automotive grade; the PIC18LF4320T-I/ML is industrial grade only and not AEC-Q100 qualified.
Recommended
USB-Free Consumer Electronics
Consumer devices that require moderate processing power without USB connectivity can leverage the PIC18LF4320T-I/ML's 8 KB flash and USART plus MSSP peripherals for peripheral interconnect. Typical uses include electronic toys, digital thermostats, simple point-of-sale terminals, and educational electronics kits. The MPLAB XC8 C compiler support allows developers to write portable firmware, while ICSP enables in-circuit programming during production. The 44-VQFN package suits miniaturized consumer form factors.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4320T-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF4320-I/ML | PIC18F4320-I/ML | PIC18LF4320T-I/PT | PIC18LF4221-I/ML | PIC18LF4220-I/ML |
|---|---|---|---|---|---|---|
| Package | 44-VQFN (ML) | 44-VQFN (ML) - same | 44-VQFN (ML) - same | 44-TQFP (PT) - pin-compatible electrically, different PCB footprint | 44-VQFN (ML) - same | 44-VQFN (ML) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash Memory | 8 KB | 8 KB | 8 KB | 8 KB | 4 KB (-50%) | 4 KB (-50%) |
| RAM | 512 bytes | 512 bytes | 512 bytes | 512 bytes | 256 bytes (-50%) | 256 bytes (-50%) |
| Operating Voltage | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 4.2 V to 5.5 V (F variant) | 2.0 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V |
| Max CPU Speed | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 36 |
| ADC | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels |
| Packaging Format | Tape & Reel | Tray | Tray | Tape & Reel | Tray | Tray |
Key Differentiators
- Low-voltage LF operation down to 2.0 V (vs PIC18F4320-I/ML)
- Tape & Reel packaging for high-volume assembly (vs PIC18LF4320-I/ML)
- VQFN package with exposed thermal pad (vs PIC18LF4320T-I/PT)
- Highest flash density in 44-VQFN LF family (vs PIC18LF4221-I/ML)
Design Notes
The 44-pin VQFN (ML) package features an exposed thermal pad on the underside that MUST be soldered to a sufficiently large copper pour (typically at least 1 square inch) connected to the ground plane. Failure to solder the exposed pad will result in poor thermal performance and potential reliability issues under sustained load. Place decoupling capacitors (100 nF ceramic plus 10 uF bulk) as close as possible to each VDD pin pair to minimize switching noise.
The PIC18LF4320T-I/ML operates from 2.0 V to 5.5 V as an LF variant. nanoWatt Sleep mode reduces quiescent current to approximately 100 nA typical, but peripheral modules left enabled can increase this by orders of magnitude. Always disable unused peripherals via their PMDx registers before entering Sleep. For battery-powered designs, choose the LF variant specifically; do not assume F-variant parts will operate reliably below 4.2 V.
Do not confuse the PIC18LF4320T-I/ML (low-voltage LF variant, 2.0-5.5 V) with the PIC18F4320-I/ML (5 V F variant, 4.2-5.5 V). The two parts share pinout but have different voltage specifications and ADC performance characteristics. Also verify configuration bits match your application: oscillator selection (HS vs XT vs RC), Watchdog Timer enable, Brown-out Reset voltage, and Low-Voltage Programming disable must all be set correctly in the CONFIG registers.
Place the ICSP connector footprint (RB6/PGC, RB7/PGD, MCLR/VPP) at the board edge for easy in-circuit programming access during production. Route MCLR with a pull-up resistor to VDD and consider adding a capacitor to ground for noise filtering. Keep analog input traces short and away from digital switching signals to minimize ADC noise coupling; use a ground guard ring around analog input pins for best ADC accuracy.
Compliance Information
RoHS and lead-free compliant per Microchip product page. Industrial -40C to +85C temperature grade; NOT AEC-Q100 qualified - select PIC18F automotive-grade variants for vehicle applications. Conflict-minerals compliant per Microchip policy.
