PIC18F4423T-I/PT - 8-bit MCU, 16KB Flash, 36 I/O, TQFP-44 | Microchip
MPN: PIC18F4423T-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.12 | $3.12 |
| 10 | $2.84 | $28.40 |
| 100 | $2.55 | $255.00 |
| 500 | $2.21 | $1,105.00 |
| 1,000 | $1.97 | $1,970.00 |
PIC18F4423T-I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer built around an 8-bit data path, optimized for embedded control tasks such as sensor reading, motor driving, user-interface handling, and low-to-moderate bandwidth communication. The PIC18 family sits within Microchip's 8-bit MCU hierarchy (PIC10/12/16/18) and is targeted at applications that require more peripherals and code space than baseline PIC16 parts but do not need the 16-bit dsPIC or 32-bit SAM architectures. Within that hierarchy the PIC18F4423 belongs to the 28/40/44-pin high-performance, enhanced-flash sub-family with nanoWatt power management and an integrated 10-bit A/D converter.
Key features of this part include 16 KB of self-programmable flash, nanoWatt technology for power-managed sleep and idle modes, a 10-bit A/D converter with up to 13 input channels, two analog comparators, a hardware USART, an MSSP module supporting SPI and I2C (both Master and Slave), and four 16-bit timer/counters. The 44-pin TQFP package exposes two capture/compare/PWM (CCP) modules plus one Enhanced CCP (ECCP) module, providing flexible PWM control for motor, lighting, and power-conversion loops. CIP (Core Independent Peripherals) functions let the timers, comparators, and PWM run autonomously without CPU intervention.
Architecturally the part uses a 16-bit instruction word with an 8-bit data bus, an 8x8 hardware multiplier, and a 31-level hardware stack. The enhanced flash controller supports self-programming and ICSP (In-Circuit Serial Programming) via two pins, allowing in-field firmware updates. Hardware-level interrupt handling, context saving on stack, and a vectored interrupt structure reduce jitter in real-time control loops. The instruction set is largely upward-compatible with the PIC16 family, easing migration of legacy firmware.
Typical applications include industrial control and sensor interface boards, low-cost HMI panels, small motor-control BLDC or stepper drivers, USB-to-UART bridges (when paired with an external transceiver), battery chargers, white-goods appliances, and general-purpose 5 V embedded designs that need 16 KB of code and a handful of analog inputs. The wide industrial temperature window also makes it suitable for outdoor installations and automotive under-hood subsystems outside the AEC-Q100 envelope.
Design consideration: when migrating to PIC18F46J11 or PIC18F46J50 the I/O mapping is not strictly identical - verify peripheral remapping tables before PCB respin. For noise-sensitive analog readings, route the analog VREF+ pin separately from digital VDD and add bulk-decoupling of at least 10 µF at the supply pin.
This page synthesizes distributor pricing, drop-in TQFP-44 alternatives, and practical design notes not found in the manufacturer datasheet, helping engineers decide whether the PIC18F4423T-I/PT is the right fit for a 5 V, 16 KB-code, 36-I/O embedded design in 2026.
Drop-in alternatives for PIC18F4423T-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 PIC18F4423T-I/PT (same form factor and footprint) — differing in Operating Temperature, Package, ADC, Timers, Communication.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
No drop-in alternatives available for this product.
Request AlternativesPIC18F4423T-I/PT Maximum Ratings & Electrical Characteristics
| Architecture | PIC18 8-bit enhanced RISC |
| Program Memory (Flash) | 16 KB |
| Data RAM | 768 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (16 MIPS) |
| Supply Voltage (VDD) | 4.2 V to 5.5 V |
| I/O Pins | 36 |
| A/D Converter | 10-bit, up to 13 channels |
| Analog Comparators | 2 |
| Timers (16-bit) | 4 (Timer0/1/2/3) |
| CCP / ECCP Modules | 2 CCP + 1 ECCP |
| Communication | 1x USART (EUSART), 1x MSSP (SPI / I2C) |
| Operating Temperature | -40 °C to +85 °C (Industrial) |
| Package | TQFP-44 (PT), 10x10 mm |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC18F4423T-I/PT Pin Configuration
| Pin 1 | MCLR — Master Clear (reset) input, drive low to reset |
| Pin 2 | RA0/AN0 — Digital I/O / analog input channel 0 |
| Pin 3 | RA1/AN1 — Digital I/O / analog input channel 1 |
| Pin 4 | RA2/AN2/VREF- — Digital I/O / analog input / ADC VREF- |
| Pin 5 | RA3/AN3/VREF+ — Digital I/O / analog input / ADC VREF+ |
| Pin 6 | RA4/T0CKI — Digital I/O / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — Digital I/O / analog input / SPI slave select |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKI/RA7 — External clock input / oscillator pin 1 |
| Pin 10 | OSC2/CLKO/RA6 — Oscillator pin 2 / system clock output |
| Pin 11 | RC0/T1OSO/T1CKI — Digital I/O / Timer1 oscillator output / clock input |
| Pin 12 | RC1/T1OSI/CCP2 — Digital I/O / Timer1 oscillator input / CCP2 PWM |
| Pin 13 | RC2/CCP1 — Digital I/O / CCP1 PWM output |
| Pin 14 | RC3/SCK/SCL — Digital I/O / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — Digital I/O / SPI data in / I2C data |
| Pin 16 | RC5/SDO — Digital I/O / SPI data out |
| Pin 17 | RC6/TX/CK — Digital I/O / EUSART TX / clock |
| Pin 18 | RC7/RX/DT — Digital I/O / EUSART RX / data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply 4.2-5.5 V |
| Pin 21 | RB0/INT0/FLT0 — Digital I/O / external interrupt 0 / ECCP fault input |
| Pin 22 | RB1/INT1 — Digital I/O / external interrupt 1 |
| Pin 23 | RB2/INT2 — Digital I/O / external interrupt 2 |
| Pin 24 | RB3/CCP2 — Digital I/O / CCP2 PWM alternate |
| Pin 25 | RB4 — Digital I/O / interrupt-on-change |
| Pin 26 | RB5 — Digital I/O / interrupt-on-change |
| Pin 27 | RB6/PGC — Digital I/O / ICSP clock |
| Pin 28 | RB7/PGD — Digital I/O / ICSP data |
| Pin 29 | VSS — Ground reference |
| Pin 30 | VDD — Positive supply 4.2-5.5 V |
| Pin 31 | RD0/PSP0 — Digital I/O / parallel slave port bit 0 |
| Pin 32 | RD1/PSP1 — Digital I/O / parallel slave port bit 1 |
| Pin 33 | RD2/PSP2 — Digital I/O / parallel slave port bit 2 |
| Pin 34 | RD3/PSP3 — Digital I/O / parallel slave port bit 3 |
| Pin 35 | RD4/PSP4 — Digital I/O / parallel slave port bit 4 |
| Pin 36 | RD5/PSP5 — Digital I/O / parallel slave port bit 5 |
| Pin 37 | RD6/PSP6 — Digital I/O / parallel slave port bit 6 |
| Pin 38 | RD7/PSP7 — Digital I/O / parallel slave port bit 7 |
| Pin 39 | VSS — Ground reference |
| Pin 40 | VDD — Positive supply 4.2-5.5 V |
| Pin 41 | RE0/RD/AN5 — Digital I/O / parallel port read / analog input channel 5 |
| Pin 42 | RE1/WR/AN6 — Digital I/O / parallel port write / analog input channel 6 |
| Pin 43 | RE2/CS/AN7 — Digital I/O / parallel port chip-select / analog input channel 7 |
| Pin 44 | AVDD — Analog positive supply, route separately from VDD |
Typical Applications
PIC18F4423T-I/PT is suitable for 6 applications: Industrial Sensor Interface Board, Small BLDC or Stepper Motor Controller, White-Goods Appliance Control, Battery Charger / Power Management Front-End, USB-to-UART Bridge Module, General-Purpose 5V Hobbyist / Education Platform.
Industrial Sensor Interface Board
The PIC18F4423T-I/PT fits industrial sensor interface boards because its 10-bit ADC with up to 13 input channels can digitize thermocouple, RTD, pressure transducer, and 4-20 mA current-loop signals with 4.88 mV resolution at 5 V. The 36 digital I/O pins handle multiple switch inputs, relay outputs, and alarm LEDs without external multiplexers. The 16 KB flash accommodates 4-20 mA loop transmitter firmware plus Modbus RTU stacks. Wide 4.2-5.5 V supply tolerates 24 V industrial rails down-regulated to 5 V. The -40 °C to +85 °C industrial temperature range suits unheated factory enclosures.
Recommended
Small BLDC or Stepper Motor Controller
The PIC18F4423T-I/PT drives small BLDC or stepper motors through its 2 CCP plus 1 ECCP module, delivering up to three complementary PWM channels at up to 40 kHz with dead-band control. The ECCP supports half-bridge, full-bridge, and single-PWM modes needed for trapezoidal commutation. Hardware timers measure back-EMF zero-crossing without CPU overhead, freeing the core for sensorless startup algorithms. The 36 I/O lines handle Hall sensors, encoder inputs, and direction/enable signals. The 16 KB flash accommodates sensorless FOC or 6-step commutation tables for low-voltage fans and pumps.
Recommended
White-Goods Appliance Control
White-goods appliances such as washing machines, dishwashers, and microwave ovens use the PIC18F4423T-I/PT because its 16 KB flash is sufficient for user-interface state machines, sensor processing, and safety interlocks. The 36 I/O drive seven-segment displays, keypads, buzzer, and triac outputs without external logic. The 10-bit ADC reads water level, temperature, and motor current. NanoWatt power management brings quiescent current below 1 µA in standby to meet Energy Star idle requirements. The industrial -40 °C to +85 °C range handles unheated garage and laundry-room environments.
Recommended
Battery Charger / Power Management Front-End
The PIC18F4423T-I/PT fits lead-acid and Li-ion charger front-ends because its 10-bit ADC monitors battery voltage and charge current to within 0.5 percent, while the ECCP module drives a synchronous buck MOSFET pair via PWM. The 36 I/O lines handle charging-state LEDs, fault relays, and SMBus / I2C to gas-gauge ICs. The 16 KB flash implements CC-CV charge profiles with temperature-compensation lookup tables. The 4.2-5.5 V supply is compatible with 5 V USB input plus 12-24 V adapter down-conversion, common in consumer battery products.
Recommended
USB-to-UART Bridge Module
The PIC18F4423T-I/PT paired with an external USB transceiver like MCP2200 implements a USB-to-UART bridge for legacy serial peripherals. The EUSART handles RS-232/RS-485 traffic at up to 115.2 kbps while the MSSP drives SPI peripherals. The 36 I/O expose additional GPIO for flow-control lines (RTS/CTS/DTR). The 16 KB flash holds USB CDC class driver state machines and bootloader firmware. Industrial temperature range suits factory-floor gateways and point-of-sale terminals that convert legacy serial devices to USB.
Recommended
General-Purpose 5V Hobbyist / Education Platform
The PIC18F4423T-I/PT is well suited as a 5 V general-purpose hobbyist and education MCU because its 5 V tolerance removes the level-shifter hurdle common in modern 3.3 V designs, and its 16 KB flash accommodates full projects with bootloader overhead. The 36 I/O and 13 ADC channels let students interface LEDs, buttons, character LCDs, and potentiometers without external mux. MPLAB X IDE, XC8 compiler, and PICkit 5 programmer support the part for free. Industrial temperature range lets the same firmware ship in commercial products without re-validation.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4423T-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F4423-I/PT | PIC18F4420T-I/PT | PIC18F4523-I/PT | PIC18F43K22-I/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | TQFP-44 (PT) | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same | TQFP-44 (PT) - same |
| Program Flash | 16 KB | 16 KB | 16 KB | 32 KB | 8 KB |
| Data RAM | 768 bytes | 768 bytes | 768 bytes | 1536 bytes | 512 bytes |
| Maximum CPU Speed | 40 MHz (16 MIPS) | 40 MHz (16 MIPS) | 40 MHz (10 MIPS) | 40 MHz (16 MIPS) | 64 MHz (16 MIPS) |
| Supply Voltage | 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 | 2.3 V to 5.5 V |
| I/O Pins | 36 | 36 | 36 | 36 | 36 |
| A/D Converter | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 13 channels | 10-bit, 17 channels |
| CCP Modules | 2 CCP + 1 ECCP | 2 CCP + 1 ECCP | 2 CCP + 1 ECCP | 2 CCP + 1 ECCP | 3 CCP |
| Approx. Unit Price (1k qty) | $1.97 | $1.94 (tray discount) | $1.85 | $2.40 | $2.10 |
Key Differentiators
- Tape & Reel packaging for pick-and-place lines (vs PIC18F4423-I/PT)
- Doubles flash for firmware headroom (vs PIC18F4523-I/PT)
- Newer K-series silicon with wider supply range (vs PIC18F43K22-I/PT)
Design Notes
Place at least one 10 µF bulk-decoupling capacitor and a 0.1 µF ceramic decoupling capacitor as close as possible to each VDD pin pair on the PIC18F4423T-I/PT. Route analog AVDD separately from digital VDD with a ferrite bead to keep ADC readings clean - the 10-bit ADC has only 4.88 mV resolution at 5 V, so 100 mV of digital-rail noise coupling into VREF+ will degrade effective accuracy by 10 LSBs. Estimated: at 40 MHz with all peripherals active the core draws about 12 mA, so the regulator must source at least 30 mA including I/O sink/source currents.
The TQFP-44 package has a thermal resistance of approximately 60 °C/W. Estimated: at 5 V supply and full-speed operation the part draws ~12 mA, dissipating only 60 mW worst case, so thermal management is generally not a concern. However, if the design is housed in a sealed enclosure with elevated ambient (>50 °C), verify that junction temperature stays below 125 °C. The industrial -40 °C to +85 °C operating range is rated for ambient air temperature; derating may be needed in still-air environments.
When laying out a 4-layer PCB for the PIC18F4423T-I/PT, place a continuous ground plane on layer 2 directly under the IC and avoid routing digital signals across that plane. Keep the 40 MHz crystal (or resonator) within 5 mm of pins 9-10 (OSC1/OSC2) and guard the traces with a ground ring to avoid coupling noise into the clock. Reserve one GND via per VDD pin pair for low-impedance return paths. Expose MCLR (pin 1) through a 10 kΩ pull-up to VDD, optionally with a 100 nF cap to ground for manual-reset debounce.
Do not exceed the 5.5 V absolute maximum on VDD - the PIC18F4423 is a 5 V part, not a 3.3 V part, but the I/O pins will tolerate brief transients to 5.5 V only. The MCLR pin has an internal clamp; do not drive MCLR externally beyond 13.5 V or you will forward-bias the ESD clamp. Configure the CONFIG register's oscillator, watchdog, and brown-out settings before exiting Reset - leaving them at default may cause runaway code or fail to start with low-voltage rails. Always read the latest errata DS80233 before committing to a layout.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - for automotive, consider PIC18F46K80-I/PT or PIC18F25K80T-I/SS. Halogen-free per Microchip environmental certification program.