PIC18LF4423-I/PT - 8-Bit 40MHz 16KB Flash MCU | Microchip
MPN: PIC18LF4423-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.42 | $5.42 |
| 10 | $4.91 | $49.10 |
| 100 | $4.36 | $436.00 |
| 500 | $3.95 | $1,975.00 |
| 1,000 | $3.58 | $3,580.00 |
PIC18LF4423-I/PT Overview
What is a PIC18 microcontroller? PIC18 microcontrollers are 8-bit RISC MCUs built on Microchip's enhanced Harvard architecture, supporting up to 16 MIPS throughput with a 16-bit instruction word and 8-bit data path. They occupy the mid-tier of the PIC family hierarchy: PIC microcontroller -> 8-bit MCU -> enhanced RISC core -> PIC18 sub-family -> peripheral-rich variants with ADC, PWM, and communication peripherals.
Key features include 36 digital I/O pins, a 10-bit A/D converter with up to 13 channels, multiple serial interfaces (EUSART, MSSP for SPI/I2C), Capture/Compare/PWM modules, and nanoWatt Technology for power-managed sleep modes. The 40 MHz Fosc yields 100 ns instruction cycle with 4x PLL options, supporting demanding real-time control tasks.
The device uses Harvard bus architecture with separate program Flash and data SRAM paths, plus internal 32 kHz oscillator and PLL for flexible clocking. On-board self-programmability via ICSP enables field firmware upgrades, while the enhanced instruction set adds hardware multiply and direct register operations, simplifying C compiler code generation for portable firmware.
Typical applications include industrial control panels, HVAC sensor interfaces, low-power consumer appliances, USB/HID peripherals, and battery-powered instrumentation. Its low-voltage LF operation makes it suitable for 2-3 AA cell designs or 3.3V system rails where standard PIC18F parts would otherwise be incompatible.
Key design consideration: the wide 2.0-5.5V supply range provides flexibility, but designers must respect Vdd minimums during A/D conversions (typically 3.0V for specified 10-bit accuracy); configure ADC acquisition time accordingly.
This page consolidates distributor stock data, parametric drop-in alternatives, and engineering design notes drawn from Microchip documentation to help embedded engineers select and qualify the PIC18LF4423 quickly.
Drop-in alternatives for PIC18LF4423-I/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 PIC18LF4423-I/PT (same form factor and footprint) — differing in Package, Timers, RAM, I/O Pins, MSL Level.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF4420-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4423-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4523-I/PT
✅ Drop-In✓ In Stock
$5 / Unit
View Datasheet →PIC18F4523-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF4423T-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.77 / Unit
View Datasheet →PIC18LF4320-I/PT
✅ Drop-In✓ In Stock
$5.9 / Unit
View Datasheet →PIC18LF4423-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit RISC (Harvard) |
| Family | PIC18F (enhanced) |
| Program Memory | 16 KB (8K x 16) Flash |
| RAM | 768 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Supply Voltage | 2.0 V to 5.5 V (LF series) |
| I/O Pins | 36 |
| A/D Converter | 10-bit, up to 13 channels |
| Package | 44-pin TQFP (PT), 10x10 mm |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Serial Interfaces | EUSART, MSSP (SPI/I2C) |
| PWM Modules | CCP/ECCP |
| Timers | Multiple 8/16-bit |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
| ICSP | In-Circuit Serial Programming |
PIC18LF4423-I/PT Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear / Programming voltage / Digital I/O RE3 |
| Pin 2 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2 / Analog input 2 / A/D reference negative |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input 3 / A/D reference positive |
| 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 — PORTE bit 0 / Read control for parallel port |
| Pin 9 | RE1/WR — PORTE bit 1 / Write control for parallel port |
| Pin 10 | RE2/CS — PORTE bit 2 / Chip select for parallel port |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI/RA7 — Crystal oscillator input / External clock / PORTA bit 7 |
| Pin 14 | OSC2/CLKO/RA6 — Crystal oscillator output / Clock output / PORTA bit 6 |
| Pin 15 | RC0/T1OSO/T13CKI — PORTC bit 0 / Timer1 oscillator output / Timer1/3 clock input |
| Pin 16 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 output |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Pin 18 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 19 | RD0/PSP0 — PORTD bit 0 / Parallel Slave Port bit 0 |
| Pin 20 | RD1/PSP1 — PORTD bit 1 / Parallel Slave Port bit 1 |
| Pin 21 | RD2/PSP2 — PORTD bit 2 / Parallel Slave Port bit 2 |
| Pin 22 | RD3/PSP3 — PORTD bit 3 / Parallel Slave Port bit 3 |
| Pin 23 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / USART asynchronous transmit / clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / USART asynchronous receive / data |
| Pin 27 | RD4/PSP4 — PORTD bit 4 / Parallel Slave Port bit 4 |
| Pin 28 | RD5/PSP5 — PORTD bit 5 / Parallel Slave Port bit 5 |
| Pin 29 | RD6/PSP6 — PORTD bit 6 / Parallel Slave Port bit 6 |
| Pin 30 | RD7/PSP7 — PORTD bit 7 / Parallel Slave Port bit 7 |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage |
| Pin 33 | RB0/INT0/AN12 — PORTB bit 0 / External interrupt 0 / Analog input 12 |
| Pin 34 | RB1/INT1/AN10 — PORTB bit 1 / External interrupt 1 / Analog input 10 |
| Pin 35 | RB2/INT2/AN8 — PORTB bit 2 / External interrupt 2 / Analog input 8 |
| Pin 36 | RB3/AN9/CCP2 — PORTB bit 3 / Analog input 9 / CCP2 output |
| Pin 37 | RB4/AN11 — PORTB bit 4 / Analog input 11 |
| Pin 38 | RB5/AN13 — PORTB bit 5 / Analog input 13 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 41 | VSS — Ground reference |
| Pin 42 | VDD — Positive supply voltage |
| Pin 43 | RC0 — PORTC bit 0 (secondary) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18LF4423-I/PT is suitable for 7 applications: Industrial Control Panels, HVAC Sensor Interface Boards, Battery-Powered Consumer Appliances, USB/HID Peripheral Devices, Low-Power Instrumentation, LED Lighting Controllers, Automotive Aftermarket Accessories.
Industrial Control Panels
The PIC18LF4423-I/PT's 36 I/O lines, 10-bit ADC, and 40 MHz throughput make it well-suited for industrial control panels requiring multiple sensor inputs and relay outputs. Its 2.0-5.5V LF range allows operation directly from 24V industrial rails stepped down to 5V or 3.3V without additional regulator stages. The EUSART and MSSP peripherals support Modbus RTU over RS-485 and I2C sensor expansion, while PWM modules drive proportional valves and motor speed controllers.
Recommended
HVAC Sensor Interface Boards
HVAC systems require multiple temperature, humidity, and pressure sensors with reliable data acquisition. PIC18LF4423-I/PT's 13-channel 10-bit ADC handles multiple analog sensor inputs while the EUSART connects to indoor/outdoor unit communication networks. The LF voltage range accommodates 24VAC-rectified supply rails common in HVAC installations. nanoWatt Technology powers sleep modes during low-activity periods to meet energy consumption requirements for ENERGY STAR rated HVAC equipment.
Recommended
Battery-Powered Consumer Appliances
Low-power consumer appliances operating from 2-3 AA cells benefit from the PIC18LF4423-I/PT's wide 2.0-5.5V LF voltage range. The MCU runs directly from the battery stack without boost regulators, simplifying BOM cost. nanoWatt sleep modes drop current consumption to microamp levels during idle periods, extending battery life for handheld appliances. The 16 KB Flash supports feature-rich user interfaces with LCD or LED segment displays driven through CCP/PWM modules.
Recommended
USB/HID Peripheral Devices
Custom USB Human Interface Devices (HID) such as programmable keypads, gaming controllers, and measurement instruments use PIC18LF4423-I/PT as the main controller. The MSSP peripheral handles SPI communication to external USB controller chips, while EUSART supports serial debugging during development. The 40 MHz Fosc provides sufficient throughput for HID polling rates above 125 Hz required by gaming applications, and 16 KB Flash holds USB descriptor tables plus custom firmware logic.
Recommended
Low-Power Instrumentation
Portable test instruments and data loggers need microamp sleep current with quick wake-up for periodic measurements. PIC18LF4423-I/PT's nanoWatt Technology provides sleep modes drawing under 100 nA typical, with RTCC wake-up from internal 32 kHz oscillator. The 10-bit ADC samples battery voltage, sensor inputs, and reference channels; 16 KB Flash stores configuration menus and calibration data; and 256 bytes EEPROM retains user settings across power cycles for handheld multimeter-style products.
Recommended
LED Lighting Controllers
Architectural and stage LED lighting controllers use PIC18LF4423-I/PT to drive multiple LED channels via hardware PWM with precise color and brightness control. ECCP modules generate complementary PWM outputs for high-side/low-side LED driver MOSFETs, while the ADC monitors current sense resistors for closed-loop brightness regulation. The MSSP peripheral drives WS2812B addressable LED strips via SPI bit-banging, and 16 KB Flash supports DMX-512 protocol parsing for stage lighting applications.
Recommended
Automotive Aftermarket Accessories
Non-safety automotive aftermarket accessories (interior lighting, gauge clusters, sensor displays) use PIC18LF4423-I/PT for cost-effective 12V-tolerant designs. The 5V-tolerant I/O with external protection handles automotive electrical environments, while the LF voltage range allows operation during cranking transients down to 6V. Note: AEC-Q100 qualification is not provided on the -I/PT Industrial grade; for OEM automotive applications, designers should select AEC-Q100 qualified PIC18 variants.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF4423-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF4420-I/PT | PIC18F4423-I/PT | PIC18LF4523-I/PT | PIC18F4523-I/PT | PIC18LF4320-I/PT |
|---|---|---|---|---|---|---|
| Package | 44-TQFP (PT) | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Flash | 16 KB | 16 KB | 16 KB | 48 KB | 48 KB | 8 KB |
| RAM | 768 bytes | 768 bytes | 768 bytes | 3,584 bytes | 3,584 bytes | 512 bytes |
| Supply Voltage | 2.0-5.5 V | 2.0-5.5 V | 4.2-5.5 V | 2.0-5.5 V | 4.2-5.5 V | 2.0-5.5 V |
| Max CPU Speed | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 36 |
| A/D Converter | 10-bit, 13 ch | 10-bit, 13 ch | 10-bit, 13 ch | 10-bit, 13 ch | 10-bit, 13 ch | 10-bit, 13 ch |
| EEPROM | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes | 256 bytes |
| Operating Temperature | -40 to +85 C | -40 to +85 C | -40 to +85 C | -40 to +85 C | -40 to +85 C | -40 to +85 C |
Key Differentiators
- Wide 2.0-5.5V Vdd range (LF series) (vs PIC18F4423-I/PT)
- Three Vdd/Vss pin pairs for noise immunity (vs PIC18LF4320-I/PT)
- Full 16 KB Flash vs downgraded 8 KB (vs PIC18LF4320-I/PT)
Design Notes
The PIC18LF4423-I/PT supports 2.0-5.5V Vdd but the 10-bit ADC requires Vdd >= 3.0V to meet specified accuracy. For designs operating near the 2.0V minimum, configure ADC acquisition time to minimum (2 TAD) and disable ADC when not in use. Place a 100 nF decoupling capacitor within 5 mm of each Vdd pin (pins 11, 32, 42) and a bulk 10 uF tantalum or ceramic capacitor near the MCU. The nanoWatt Technology sleep modes (Sleep, Idle, and PRI_RUN with peripheral clock gating) drop quiescent current to under 1 uA in Sleep mode for battery applications.
TQFP-44 layout requires 0.8 mm pitch traces with 0.4 mm clearance. Route oscillator traces (OSC1, OSC2) symmetrically with ground guard ring to minimize EMI; keep crystal traces under 10 mm total length and avoid crossing signal traces. The ICSP pins RB6/PGC and RB7/PGD must remain accessible for in-circuit programming - do not connect external loads that prevent programmer drive. The MCLR/VPP pin (pin 1) requires a 10 kohm pull-up to Vdd and a 100 nF decoupling cap for hardware reset generation.
Do not assume PIC18LF4423-I/PT and PIC18F4423-I/PT are interchangeable: PIC18F minimum Vdd is 4.2V versus PIC18LF's 2.0V. Designs using 3.3V rails must use PIC18LF variants. The configuration word bits (CONFIG1H, CONFIG2L) must be set correctly during programming - particularly the FOSC (oscillator selection) and WDTE (watchdog timer) bits. Brown-out Reset (BOR) must be enabled for battery applications or Vdd may drop below safe threshold without proper MCU reset. Ensure unused I/O pins are configured as outputs (not inputs floating) to minimize current consumption.
Compliance Information
RoHS and REACH compliant per Microchip product declaration. Industrial temperature grade -40C to +85C (I suffix). AEC-Q100 not qualified - select AEC-Q100 qualified PIC18 variants for OEM automotive. Lead-free and halogen-free per Microchip Microchip lead-free/green packaging standard.