PIC18F26Q43T-I/STX - 8-bit 64MHz 64KB Flash MCU | Microchip
MPN: PIC18F26Q43T-I/STX ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.95 | $1.95 |
| 10 | $1.78 | $17.80 |
| 100 | $1.56 | $156.00 |
| 500 | $1.38 | $690.00 |
| 1,000 | $1.22 | $1,220.00 |
| 3,000 | $1.05 | $3,150.00 |
PIC18F26Q43T-I/STX Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory, working RAM, and integrated peripherals such as ADCs, timers, communication controllers, and GPIO. The PIC18 family sits within Microchip's 8-bit MCU portfolio and is widely deployed in consumer, industrial, and IoT designs where deterministic interrupt response, low power, and rich analog integration matter more than raw clock speed.
Key features of this part include a 12-bit Analog-to-Digital Converter with Computation (ADCC) supporting capacitive voltage divider (CVD) touch sensing, three 16-bit dual PWMs providing six PWM outputs, six Direct Memory Access (DMA) controllers, vectored interrupts with selectable priority and 3-instruction-cycle fixed latency, and CLC (Configurable Logic Cell) hardware customization blocks. The device operates from 1.8 V to 5.5 V and includes XLP extreme-low-power sleep modes.
The architecture is built on an enhanced PIC18 Harvard core with 16-bit instructions, a hardware multiplier, and a 31-level stack. Internal high-frequency oscillator, PLL, and low-power LFINTOSC minimize external components. Six DMA channels offload data movement between peripherals and memory, freeing the CPU for application logic and improving real-time response in motor control, lighting, and sensor-fusion designs.
Typical applications include capacitive touch user interfaces, BLDC/PMSM motor control using the 16-bit PWMs and PGA-equipped ADCC, LED lighting and signage controllers, IoT sensor nodes, battery-powered consumer appliances, and industrial control front-ends. The combination of XLP sleep currents and DMA-driven peripherals enables long battery life in always-on systems.
When designing with the PIC18F26Q43T-I/STX, follow Microchip AN2931 and AN2407 for PCB layout guidelines, place a 0.1 µF decoupling capacitor on each VDD pin with trace length under 5 mm, and use the MPLAB X IDE with MPLAB Code Configurator (MCC) for peripheral setup. Keep in mind that the 28-pin VQFN variant differs from the 28-pin SPDIP/SOIC variants only in thermal pad connection—review the pinout diagram before routing.
This page synthesizes distributor pricing, drop-in alternatives within the PIC18-Q43 family, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18F26Q43T-I/STX — 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 PIC18F26Q43T-I/STX (same form factor and footprint) — differing in ADC, Operating Temperature, PWM, Package, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F26Q43-I/STX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26Q43-E/STX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F25Q43T-I/STX
✅ Drop-In✓ In Stock
$1.78 / Unit
View Datasheet →PIC18F24Q43T-I/STX
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26Q43T-I/STX Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit Harvard) |
| Maximum CPU Frequency | 64 MHz |
| Program Memory (Flash) | 64 KB (64K x 8) |
| SRAM | 4 KB |
| EEPROM | 1 KB |
| Supply Voltage Range | 1.8 V to 5.5 V |
| ADC | 12-bit with Computation (ADCC), supports CVD |
| PWM | Three 16-bit dual PWMs (six outputs) |
| DMA Controllers | 6 channels |
| Package | 28-VQFN (4x4 mm) |
| Operating Temperature | -40C to +85C (Industrial) |
| Low-Power Technology | XLP (eXtreme Low Power) |
| Core Independent Peripherals | CLC, CWG, NCO, DSM, SMT, CCP, PWM |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| Lead-Free | Yes |
PIC18F26Q43T-I/STX Pin Configuration
| Pin 1 | RA0/ICDDAT — Analog input 0 / ICD data |
| Pin 2 | RA1/ICSPCLK — Analog input 1 / ICD clock |
| Pin 3 | RA2 — Analog input 2 / digital I/O |
| Pin 4 | RA3 — Analog input 3 / reference voltage |
| Pin 5 | RA4 — Analog input 4 / digital I/O |
| Pin 6 | RA5 — Analog input 5 / digital I/O |
| Pin 7 | RA6 — General purpose I/O |
| Pin 8 | RA7 — General purpose I/O |
| Pin 9 | VSS — Ground reference |
| Pin 10 | VDD — Positive supply voltage |
| Pin 11 | RB0 — Port B bit 0 / interrupt-on-change |
| Pin 12 | RB1 — Port B bit 1 |
| Pin 13 | RB2 — Port B bit 2 |
| Pin 14 | RB3 — Port B bit 3 |
| Pin 15 | RB4 — Port B bit 4 |
| Pin 16 | RB5 — Port B bit 5 |
| Pin 17 | RB6/ICSPCLK — Port B bit 6 / ICD clock |
| Pin 18 | RB7/ICDDAT — Port B bit 7 / ICD data |
| Pin 19 | RC0 — Port C bit 0 |
| Pin 20 | RC1 — Port C bit 1 |
| Pin 21 | RC2 — Port C bit 2 |
| Pin 22 | RC3 — Port C bit 3 |
| Pin 23 | RC4 — Port C bit 4 |
| Pin 24 | RC5 — Port C bit 5 |
| Pin 25 | RC6 — Port C bit 6 |
| Pin 26 | RC7 — Port C bit 7 |
| Pin 27 | VSS — Ground (bonded to thermal pad) |
| Pin 28 | VDD — Positive supply voltage (bonded to thermal pad) |
Typical Applications
PIC18F26Q43T-I/STX is suitable for 6 applications: Capacitive Touch User Interface, BLDC / PMSM Motor Control, IoT Sensor Node / Battery Powered Device, LED Lighting and Signage Controllers, Industrial Control Front-End, Consumer Appliance Control Board.
Capacitive Touch User Interface
The PIC18F26Q43T-I/STX's 12-bit ADCC with hardware Capacitive Voltage Divider (CVD) and DMA offload makes it ideal for replacing mechanical buttons with capacitive sliders, wheels, or keypad matrices. The ADCC automates charge accumulation across multiple samples and applies averaging and threshold comparison, eliminating CPU-intensive scan loops. With three 16-bit SMT timers and six DMA channels, the MCU can scan 12+ electrodes while the core sleeps at sub-10 µA. Developers using the MPLAB Code Configurator mTouch plugin generate production-grade firmware in hours. The 28-VQFN 4x4 mm footprint fits behind 0.5 mm-thick glass or acrylic overlays. Compared to discrete touch ICs, integrating touch into the main MCU reduces BOM cost and simplifies FCC/CE EMI pre-compliance since touch scans stay deterministic.
Recommended
BLDC / PMSM Motor Control
The PIC18F26Q43T-I/STX drives 3-phase brushless DC motors using its three 16-bit dual PWMs (six outputs) with 15.6 ns edge resolution at 64 MHz, plus the CLC and CWG peripherals for hardware commutation and dead-band insertion. The 12-bit ADCC samples back-EMF or current-sense shunts synchronously to the PWM, while DMA moves conversion results directly to control registers without CPU involvement. Vectored interrupts with 3-cycle fixed latency ensure deterministic torque-loop response under 2 µs, suitable for sensorless field-oriented control of small appliances, fans, and e-bikes. The Configurable Logic Cells (CLC) implement hardware fault shutoff in fewer than 30 ns when overcurrent triggers the comparator. XLP sleep modes drop quiescent current below 1 µA during standby, extending battery runtime on cordless tools.
Recommended
IoT Sensor Node / Battery Powered Device
The PIC18F26Q43T-I/STX suits wireless sensor nodes that periodically wake to measure and transmit, then sleep for hours. XLP technology delivers 30 nA sleep current with RTC running, and DMA-driven ADC scanning keeps the CPU off during acquisition. The on-chip 12-bit ADCC handles temperature, light, and battery-voltage monitoring without external components. Operating voltage from 1.8 V to 5.5 V lets the device run directly from a single CR2032, 2xAA, or Li-ion cell. The CLC blocks implement wake-on-interrupt logic so external sensors trigger the MCU without burning GPIO. For Bluetooth LE bridging, designers pair this MCU with an AT-command module while the MCU manages sensors, BLE housekeeping, and secure firmware updates.
Recommended
LED Lighting and Signage Controllers
The PIC18F26Q43T-I/STX drives WS2812B, APA102, or SK6812 addressable LED strips using DMA-fed SPI or PWM channels, freeing the CPU to handle color animations, brightness compensation, and protocol translation. Three 16-bit PWMs simultaneously control warm/cool white analog LEDs for tunable-white fixtures. The 12-bit ADCC reads ambient light sensors to adjust brightness, while DMA transfers updated gamma tables without CPU intervention. XLP sleep modes drop standby power below 1 mA when lights are off. The 64 KB Flash fits DMX-512, DALI, or Matter-over-Thread protocol stacks, and the CLC blocks generate addressable-LED reset codes in hardware, eliminating software timing jitter.
Recommended
Industrial Control Front-End
The PIC18F26Q43T-I/STX serves as a robust front-end in industrial PLCs, sensor hubs, and Human-Machine Interface (HMI) terminals. The 12-bit ADCC with hardware averaging oversamples noisy industrial signals, while three UART modules handle RS-232, RS-485 Modbus, and DMX simultaneously via DMA. The Configurable Logic Cells implement fieldbus protocol encoding in hardware, offloading the CPU and improving EMC immunity. Operating from -40C to +85C (industrial grade) the part is suitable for factory-floor enclosures. The 28-VQFN package fits dense PCB layouts with thermal pad for 1+ A total pin drive, and the 64 KB Flash holds bootloader plus application firmware with field-upgrade capability.
Recommended
Consumer Appliance Control Board
The PIC18F26Q43T-I/STX powers control boards in coffee machines, washing machines, air purifiers, and microwave ovens where reliability, low BOM cost, and rich peripheral integration matter. Three 16-bit PWMs drive triac phase-cut dimmers, brushless pumps, and inverter compressors. The 12-bit ADCC reads NTC temperature sensors for closed-loop heating control with 0.1 C resolution via oversampling. CLC blocks implement safety interlocks in hardware - if a door-open sensor triggers, the PWM outputs disable within 30 ns, bypassing software faults. The 64 KB Flash accommodates USB-CDC bootloader plus appliance-specific state machines, and XLP sleep meets Energy Star standby targets below 50 mW.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F26Q43T-I/STX — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F26Q43-I/STX | PIC18F26Q43-E/STX | PIC18F25Q43T-I/STX | PIC18F24Q43T-I/STX |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-VQFN (4x4 mm) | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same | 28-VQFN (4x4) - same |
| Flash | 64 KB | 64 KB | 64 KB | 32 KB | 16 KB |
| SRAM | 4 KB | 4 KB | 4 KB | 2 KB | 1 KB |
| EEPROM | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB |
| Max CPU Clock | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +85C |
| ADC with CVD Touch | Yes (12-bit ADCC) | Yes (12-bit ADCC) | Yes (12-bit ADCC) | Yes (12-bit ADCC) | Yes (12-bit ADCC) |
| DMA Channels | 6 | 6 | 6 | 6 | 6 |
| PWM Channels | 6 (3 x 16-bit dual) | 6 (3 x 16-bit dual) | 6 (3 x 16-bit dual) | 6 (3 x 16-bit dual) | 5 (reduced pin count) |
Key Differentiators
- Highest memory in PIC18-Q43 28-pin VQFN family (vs PIC18F25Q43T-I/STX)
- Industrial-grade temperature coverage (vs PIC18F26Q43-E/STX)
- More DMA channels than predecessor PIC18-K42 family (vs PIC18F26K42T-I/SS)
- Configurable Logic Cells (CLC) provide hardware state machines (vs PIC18F26K22T-I/ML)
Design Notes
Decouple each VDD pin with a 0.1 µF X7R ceramic capacitor placed within 5 mm of the pin and connected directly to the thermal-pad ground plane. The PIC18F26Q43T-I/STX includes four VDD/SS pairs (pins 10/9, 28/27, plus internal bond to thermal pad). Adding a 10 µF bulk capacitor near the MCU helps the internal LDO during ADC burst conversions. Estimated: total inrush at 64 MHz start-up stays below 20 mA if decoupling follows Microchip AN2931 4-layer board guidelines.
The 28-VQFN package exposes a thermal pad on pin 27/28 that MUST be soldered to a corresponding copper pad on the PCB to meet thermal and electrical specs. Thermal pad should have at least 8 thermal vias (0.3 mm drill, 0.6 mm pad) connecting to an internal ground plane for heat dissipation. Keep-out zones beneath the pad prevent solder wicking into ground pours. Follow IPC-7351 land pattern recommendations for VQFN-28 4x4 mm body.
Route the external 16 MHz crystal or external clock traces as short as possible with guard traces tied to ground, and avoid routing high-speed signals (PWM, SPI) parallel to analog ADC inputs. Place the ICSP™/ICD pins (RA0/RA1 and RB6/RB7) on accessible test points or header pads to allow in-circuit debugging with PICkit 5 or MPLAB Snap. Separate analog and digital ground planes if the design mixes 12-bit ADC signals with PWM switching above 100 kHz.
Configuration word bits (CONFIG1-7) must be set correctly or the MCU may lock up. The WDT, BOR, and PLL settings influence startup time and watchdog behavior - configure BOR for 2.85V minimum to ensure safe operation from 3.3V rails. The DEBUG fuse must be enabled if you plan to debug later; otherwise, MPLAB X cannot reattach without erasing. Do not exceed 5.5V on any I/O pin even though the absolute maximum is 6.5V; permanent damage occurs at sustained overvoltage.
Compliance Information
RoHS and lead-free per Microchip product environmental compliance. Industrial temperature grade -40C to +85C. Not AEC-Q100 qualified; see automotive-grade PIC18F26Q43 with VAO suffix for AEC-Q100. Conflict minerals CMRT filed with Microchip.
