PIC18F43K20-I/PT - 8-bit PIC XLP MCU 8KB Flash 64MHz | Microchip
MPN: PIC18F43K20-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.2 | $4.20 |
| 10 | $3.78 | $37.80 |
| 100 | $3.36 | $336.00 |
| 500 | $2.94 | $1,470.00 |
| 1,000 | $2.69 | $2,690.00 |
PIC18F43K20-I/PT Overview
An 8-bit microcontroller is a single-chip computer that integrates a CPU, RAM, non-volatile program memory (FLASH/ROM), data EEPROM, and peripherals onto one silicon die. PIC microcontrollers from Microchip use a Harvard RISC architecture, placing program and data memory on separate buses to fetch instructions and operands in a single cycle. The PIC18 family extends the baseline PIC16 architecture with 16-bit instruction words, 8-bit data paths, and an extended instruction set for C-compiler efficiency.
Key features include 64 MHz operation (16 MIPS throughput), 10-bit ADC with up to 14 channels, enhanced CCP modules, EUSART, MSSP (SPI/I2C), two analog comparators, and four timers. The "XLP" (eXtreme Low Power) label marks nanoWatt Technology devices whose sleep current falls below 100 nA typical, enabling years of operation from a single coin cell. The 44-TQFP package provides ample I/O for human-interface, sensor-front-end, and motor-control designs.
Typical applications include consumer appliances, industrial sensor nodes, USB-to-UART bridges, battery-powered instrumentation, and hobby/educational platforms where the PICkit 3/4 and MPLAB X IDE ecosystem accelerates firmware development. The device's broad peripheral set and 5 V tolerance on most digital pins simplify interfacing to legacy 5 V logic without level shifters.
When designing with this part, allocate decoupling capacitance of 100 nF within 5 mm of every VDD/VSS pair and follow Microchip's "Minimum PIC MCU Connection" guideline that ties MCLR through a 10 kΩ pull-up to VDD. Industrial temperature grade ("-I") is -40 °C to +85 °C; the "-E" extended grade reaches +125 °C. Pin-compatible variants in 40-pin PDIP, 44-pin QFN, and 28-pin SPDIP packages allow mechanical migration without firmware changes.
This page synthesizes distributor pricing, drop-in alternative recommendations, and PCB design guidance not consolidated in the manufacturer datasheet alone.
Drop-in alternatives for PIC18F43K20-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 PIC18F43K20-I/PT (same form factor and footprint) — differing in Package, Timers, Core Architecture, Program Memory (Flash), ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F43K20-E/PT
✅ Drop-In✓ In Stock
$2.51 / Unit
View Datasheet →PIC18F45K20-I/PT
✅ Drop-In✓ In Stock
$2.95 / Unit
View Datasheet →PIC18F46K20-I/PT
✅ Drop-In✓ In Stock
$1.78 / Unit
View Datasheet →PIC18F4331-I/PT
✅ Drop-In✓ In Stock
$3.05 / Unit
View Datasheet →PIC18F4320-I/PT
✅ Drop-In✓ In Stock
$3.62 / Unit
View Datasheet →PIC18F46J11-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F43K20-I/PT Maximum Ratings & Electrical Characteristics
| Family | PIC® XLP™ 18K |
| Core | PIC 8-bit RISC |
| Program Memory Size | 8 KB (4K x 16) FLASH |
| RAM Size | 768 bytes |
| EEPROM Size | 256 bytes |
| Maximum Clock Frequency | 64 MHz (16 MIPS) |
| Supply Voltage Range | 1.8 V to 5.5 V (ADC: 4.2 V to 5.5 V) |
| I/O Pins | 36 |
| ADC | 10-bit, up to 14 channels |
| Package | 44-TQFP (PT), 10x10 mm |
| Mounting Type | Surface Mount |
| Operating Temperature | -40 °C to +85 °C (Industrial -I grade) |
| Communication Interfaces | EUSART, MSSP (SPI/I²C), USB (via bootloader) |
| Timers | 4 (Timer0/1/2/3) |
| Analog Comparators | 2 |
| Enhanced CCP Modules | 2 (ECCP + CCP) |
| Low-Power Technology | nanoWatt (XLP) |
| RoHS Status | Compliant |
PIC18F43K20-I/PT Pin Configuration
| Pin 1 | MCLR/VPP — Master Clear (Reset) input / programming voltage |
| 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 / VREF- |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / analog input 3 / VREF+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SPI SS |
| Pin 8 | RE0/RD — PORTE bit 0 / read control (parallel slave) |
| Pin 9 | RE1/WR — PORTE bit 1 / write control (parallel slave) |
| Pin 10 | RE2/CS — PORTE bit 2 / chip select (parallel slave) |
| Pin 11 | VDD — Positive supply voltage |
| Pin 12 | VSS — Ground reference |
| Pin 13 | OSC1/CLKI/RA7 — Crystal input / external clock |
| Pin 14 | OSC2/CLKO/RA6 — Crystal output / clock output |
| Pin 15 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator |
| Pin 16 | RC1/T1OSI — PORTC bit 1 / Timer1 oscillator |
| Pin 17 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 |
| Pin 18 | RC3/SCL/SCK — PORTC bit 3 / I2C SCL / SPI SCK |
| Pin 19 | RD0 — PORTD bit 0 |
| Pin 20 | RD1 — PORTD bit 1 |
| Pin 21 | RD2 — PORTD bit 2 |
| Pin 22 | RD3 — PORTD bit 3 |
| Pin 23 | RC4/SDA/SDI — PORTC bit 4 / I2C SDA / SPI SDI |
| Pin 24 | RC5/SDO — PORTC bit 5 / SPI SDO |
| Pin 25 | RC6/TX/CK — PORTC bit 6 / EUSART TX / clock |
| Pin 26 | RC7/RX/DT — PORTC bit 7 / EUSART RX / data |
| Pin 27 | RD4 — PORTD bit 4 |
| Pin 28 | RD5/P1B — PORTD bit 5 / PWM enhanced output 1B |
| Pin 29 | RD6/P1C — PORTD bit 6 / PWM enhanced output 1C |
| Pin 30 | RD7/P1D — PORTD bit 7 / PWM enhanced output 1D |
| Pin 31 | VSS — Ground reference |
| Pin 32 | VDD — Positive supply voltage |
| Pin 33 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Pin 34 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 35 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Pin 36 | RB3/CCP2 — PORTB bit 3 / Capture-Compare-PWM 2 |
| Pin 37 | RB4 — PORTB bit 4 |
| Pin 38 | RB5 — PORTB bit 5 |
| Pin 39 | RB6/PGC — PORTB bit 6 / ICSP clock |
| Pin 40 | RB7/PGD — PORTB bit 7 / ICSP data |
| Pin 41 | RE3 — PORTE bit 3 |
| Pin 42 | AVDD — Analog positive supply |
| Pin 43 | AVSS — Analog ground |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18F43K20-I/PT is suitable for 7 applications: Industrial Sensor Node / Data Logger, USB HID / CDC Bridge Device, Consumer Appliance Control Board, Battery-Powered Wearable / Portable Instrument, Hobbyist / Educational Development Platform, Automotive Interior / Aftermarket Module, Home Automation / IoT Edge Controller.
Industrial Sensor Node / Data Logger
The PIC18F43K20-I/PT is well suited for industrial 4-20 mA sensor nodes and data loggers because its 64 MHz / 16 MIPS core digitizes 14 ADC channels at the 10-bit level without CPU saturation, while the 1.8-5.5 V supply range accepts direct Li-ion or 24 V-buck-derived rails. Its nanoWatt XLP sleep current (~100 nA typical) lets a 1 Ah primary cell run years between service intervals. Place the MCU between the analog front-end (e.g. MCP3421 18-bit ADC) and an EUSART-linked wireless module (RN2483 LoRa); the 256-byte EEPROM stores 8-bit calibration constants safely across millions of write cycles.
Recommended
USB HID / CDC Bridge Device
The PIC18F43K20-I/PT hosts low-speed USB HID or CDC firmware using the on-chip MSSP SPI for external PHY-less bridging and the EUSART for legacy RS-232, simplifying PC-side virtual-COM-port cables and HID game controllers. Its 8 KB FLASH holds a USB stack (Microchip MLA) plus application code; 36 I/O drive button matrices and LED indicators. Power is normally bus-powered 5 V via USB, falling inside the device's 1.8-5.5 V supply range. Brown-out reset at 2.0 V protects against unstable bus enumeration.
Recommended
Consumer Appliance Control Board
In washing machines, induction cooktops and air-conditioner indoor units, the PIC18F43K20-I/PT drives 36 I/O lines that scan keypads, multiplex 7-segment displays and gate triac drivers through opto-isolated MOC3021 parts. Its 64 MHz throughput handles software PWM for fan-speed or compressor control at 20 kHz switching frequency, leaving headroom for safety supervision. The 10-bit ADC reads NTC thermistors for over-temperature protection. Industrial -40/+85 °C grade survives under-hood thermal stress in appliance chassis.
Recommended
Battery-Powered Wearable / Portable Instrument
Battery-powered wearables benefit from the PIC18F43K20-I/PT's nanoWatt XLP technology, which drops quiescent current below 1 µA in sleep mode while RTC-based interrupts wake the CPU for sensor polling at 1 Hz. The 1.8 V minimum supply accepts a single alkaline or rechargeable NiMH cell directly, eliminating boost converters in slim wrist-worn enclosures. EUSART links to Bluetooth modules (RN42) for smartphone pairing, while 36 I/O drive small OLED panels via SPI. Typical duty-cycled power budget stays under 50 µA average.
Recommended
Hobbyist / Educational Development Platform
The PIC18F43K20-I/PT is a popular teaching MCU because the PICkit 3/4 and MPLAB X IDE toolchain are free, and 44-pin TQFP breakout boards expose every pin with 0.1" headers for breadboarding peripherals. Students learn C, assembly and interrupt-driven design on a real 8-bit RISC core, with the 8 KB FLASH enough for lab exercises (PWM motor control, UART terminal echo, ADC thermometer) yet small enough that firmware structure matters. Compatible with the open-source XC8 compiler and the CCS PCM C compiler.
Recommended
Automotive Interior / Aftermarket Module
While not AEC-Q100 qualified, the PIC18F43K20-I/PT is widely used in non-safety automotive interior modules such as ambient-lighting controllers, custom gauge clusters and CAN-bus gauges where the EUSART plus MCP2515 SPI-CAN bridge translates J1939 frames to local displays. Its 44-pin count supports up to 36 I/O for RGB LED strings and rotary encoders, while 5 V I/O tolerance withstands load-dump transients when paired with TVS protection. Industrial -40/+85 °C grade covers cabin temperatures.
Recommended
Home Automation / IoT Edge Controller
Smart-home edge controllers and IoT sensor hubs often use the PIC18F43K20-I/PT as a low-cost Cortex/AVR alternative for mains-powered nodes where Wi-Fi modules (ESP8266) connect via UART. Its 36 I/O drive relays, zero-cross SSRs and indicator LEDs; the 10-bit ADC reads LDR, CT current sensors and analog temperature probes. With 5 V tolerance and ample FLASH, the same firmware stack can be reused across product families (PIC18F25K20 / PIC18F43K20 / PIC18F46K20) by recompiling.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F43K20-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F43K20-E/PT | PIC18F45K20-I/PT | PIC18F46K20-I/PT | PIC18F4331-I/PT | PIC18F4320-I/PT | PIC18F46J11-I/PT |
|---|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-TQFP (PT) 10x10 mm | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same | 44-TQFP (PT) - same |
| FLASH Program Memory | 8 KB | 8 KB | 16 KB (+100%) | 32 KB (+300%) | 8 KB | 8 KB | 16 KB (+100%) |
| Max Clock | 64 MHz (16 MIPS) | 64 MHz | 64 MHz | 64 MHz | 40 MHz | 40 MHz | 48 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 3.6 V (5 V tolerant I/O) |
| Operating Temperature | -40 °C to +85 °C (Industrial) | -40 °C to +125 °C (Extended) | -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 |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 36 | 34 |
Key Differentiators
- Lowest-cost 64 MHz 8-bit MCU in 44-TQFP from Microchip (vs PIC18F45K20-I/PT)
- Industrial temperature grade (-40/+85 °C) at no cost premium (vs PIC18F43K20-E/PT)
- Integrated nanoWatt XLP for ultra-low sleep current (vs PIC18F4320-I/PT)
- Single 1.8 V-5.5 V supply across entire operating range (vs PIC18F46J11-I/PT)
Design Notes
Place a 100 nF ceramic decoupling capacitor within 5 mm of every VDD/VSS pin pair (pin 11/12 and 31/32). For ADC accuracy, add a separate 10 µF + 100 nF combination on AVDD (pin 42) and route AVSS (pin 43) to a quiet ground island. Following Microchip's 'Minimum PIC MCU Connection' guideline prevents in-circuit programming failures and brown-out reset glitches on USB-powered applications.
Estimate the I/O drive budget before laying out the board: each PORTA/PORTB pin can source/sink up to 25 mA, with a per-port limit of 200 mA. For a 36-I/O design driving 36 LEDs at 10 mA, total current reaches 360 mA which exceeds the 200 mA/port rating - multiplex the LEDs or use a constant-current driver such as the MCP23S17 or ULN2003 to stay within safe operating area.
Do not leave MCLR floating: tie it through a 10 kΩ pull-up to VDD. Floating MCLR is the single most common cause of intermittent reset or programming failure. When unused, set unused I/O pins as outputs driving low (per Microchip errata DS80233). Configuration bits must be programmed last; an unconfigured device latches all pins as analog inputs, drawing parasitic current and floating during reset.
For crystal operation above 20 MHz, place the crystal and load capacitors (typically 15-33 pF) within 4 mm of OSC1/OSC2 (pins 13/14). Avoid routing digital signals under the crystal traces. For EMI-sensitive designs, use a four-layer PCB with a dedicated ground plane under the MCU, which can reduce radiated emissions by 10-15 dB.
Compliance Information
RoHS and Pb-free per Microchip product page; AEC-Q100 not qualified (industrial -40 to +85 °C grade). For AEC-Q100 automotive, consider PIC18F46K80 or PIC18F25K80 family.