PIC18F27Q43-I/SP - 8-Bit 64MHz MCU, 128KB Flash 28-SPDIP | Microchip
MPN: PIC18F27Q43-I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.46 | $34.60 |
| 100 | $3.07 | $307.00 |
| 500 | $2.77 | $1,385.00 |
| 1,000 | $2.46 | $2,460.00 |
PIC18F27Q43-I/SP Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, non-volatile program memory, working RAM, and a rich set of on-chip peripherals such as ADCs, timers, communication controllers, and PWMs. The PIC18 family uses an enhanced 8-bit Harvard architecture with modified RISC instruction set, positioned between simple 8-bit MCUs (e.g., PIC10/PIC16) and higher-end 16-bit dsPIC or 32-bit ARM Cortex-M parts. Within the XLP™ (eXtreme Low Power) lineup, the 'Q43 sub-family targets advanced real-time control with extensive Core Independent Peripherals (CIPs) that operate without CPU intervention, enabling responsive motor, lighting, and power-conversion feedback loops.
Key features of the PIC18F27Q43-I/SP include 128 KB self-programmable Flash with code protection, a 12-bit ADC with up to 200 ksps conversion rate and automated post-processing math, six independent DMA channels for peripheral-to-memory transfers, vectored interrupt controller with fixed latency of three instruction cycles, and the Functional Safety diagnostics library for IEC 61508 SIL 2/3 capable designs. The 'I/SP suffix denotes the industrial temperature grade (-40°C to +85°C) in the through-hole 28-SPDIP package.
Typical applications include industrial sensor conditioning, capacitive touch user interfaces, low-power IoT edge nodes, white goods and HVAC control, BLDC/PMSM motor control with field-oriented control, LED lighting drivers with smooth dimming, and battery-powered instrumentation where XLP sleep currents extend operating life. The integrated ADCC and 16-bit PWMs are particularly well suited to digital power conversion and resonant converter control loops.
When designing with this part, take care that the 28-SPDIP package has limited thermal headroom and slower heat dissipation than surface-mount QFN variants; for reflow-only assemblies the PIC18F27Q43-I/SO or -I/SS is the recommended counterpart. Provide a clean 3.0-5.5 V supply with adequate decoupling near the VDD pins and route the MCLR reset circuit with the recommended RC network. For new designs, also evaluate the PIC18F27Q10 as a lower-cost follow-on.
Drop-in alternatives for PIC18F27Q43-I/SP — 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 PIC18F27Q43-I/SP (same form factor and footprint) — differing in Package, ADC, Operating Temperature, Mounting Type, DAC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F27Q43-E/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.92 / Unit
View Datasheet →PIC18F27Q43-I/SP
✅ Drop-In✓ In Stock
$2.46 / Unit
View Datasheet →PIC18F27Q43-E/SPB19
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F25Q43-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.72 / Unit
View Datasheet →PIC18F26Q43-I/SP
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F27Q43-I/SPVAO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F27Q43-I/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit enhanced Harvard |
| Family | PIC18-Q43 (Functional Safety / XLP) |
| CPU Speed | 64 MHz (16 MIPS) |
| Program Memory | 128 KB Flash |
| RAM | 8 KB |
| EEPROM | 1 KB |
| DMA Controllers | 6 channels |
| ADC | 12-bit ADC with Computation (ADCC) |
| DAC | 5-bit DAC |
| PWM | Three 16-bit dual PWMs (six outputs) |
| Package | 28-SPDIP (SP) |
| Operating Temperature | -40C to +85C (industrial, I grade) |
| Supply Voltage | 1.8 V to 5.5 V |
| Mounting Type | Through-Hole (THT) |
| RoHS Status | Compliant |
PIC18F27Q43-I/SP Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (reset) input / PORTE bit 3 |
| Pin 2 | RA0 — PORTA bit 0; analog/digital I/O |
| Pin 3 | RA1 — PORTA bit 1; analog/digital I/O |
| Pin 4 | RA2 — PORTA bit 2; analog/digital I/O |
| Pin 5 | RA3 — PORTA bit 3; analog/digital I/O |
| Pin 6 | RA4 — PORTA bit 4; analog/digital I/O |
| Pin 7 | RA5 — PORTA bit 5; analog/digital I/O |
| Pin 8 | RA6 — PORTA bit 6; analog/digital I/O |
| Pin 9 | RA7 — PORTA bit 7; analog/digital I/O |
| Pin 10 | VSS — Logic ground reference |
| Pin 11 | VDD — Logic power supply (1.8 V to 5.5 V) |
| Pin 12 | RB0 — PORTB bit 0; analog/digital I/O |
| Pin 13 | RB1 — PORTB bit 1; analog/digital I/O |
| Pin 14 | RB2 — PORTB bit 2; analog/digital I/O |
| Pin 15 | RB3 — PORTB bit 3; analog/digital I/O |
| Pin 16 | RB4 — PORTB bit 4; analog/digital I/O |
| Pin 17 | RB5 — PORTB bit 5; analog/digital I/O |
| Pin 18 | RB6 — PORTB bit 6; analog/digital I/O; ICSPCLK |
| Pin 19 | RB7 — PORTB bit 7; analog/digital I/O; ICSPDAT |
| Pin 20 | VSS — Logic ground reference |
| Pin 21 | VDD — Logic power supply (1.8 V to 5.5 V) |
| Pin 22 | RC0 — PORTC bit 0; analog/digital I/O |
| Pin 23 | RC1 — PORTC bit 1; analog/digital I/O |
| Pin 24 | RC2 — PORTC bit 2; analog/digital I/O |
| Pin 25 | RC3 — PORTC bit 3; analog/digital I/O |
| Pin 26 | RC4 — PORTC bit 4; analog/digital I/O |
| Pin 27 | RC5 — PORTC bit 5; analog/digital I/O |
| Pin 28 | RC6 — PORTC bit 6; analog/digital I/O |
| Pin 29 | RC7 — PORTC bit 7; analog/digital I/O |
Typical Applications
PIC18F27Q43-I/SP is suitable for 7 applications: Capacitive Touch User Interface, Industrial Sensor Conditioning, BLDC / PMSM Motor Control, White-Goods and HVAC Control, LED Lighting Driver with Smooth Dimming, Battery-Powered IoT Edge Sensor, Functional Safety Sensor Module.
Capacitive Touch User Interface
The PIC18F27Q43-I/SP is ideal for capacitive touch keypads, sliders, and proximity sensors in appliances, IoT devices, and human-machine interfaces (HMIs). Its 12-bit ADC with Computation (ADCC) module directly supports Capacitive Voltage Divider (CVD) techniques with built-in averaging, oversampling, and threshold comparison, enabling mTouch® implementations without an external touch controller. The on-chip DMA offloads scanning, while XLP sleep modes keep touch-scan current draw in the single-digit microamp range, preserving battery life. The 28-SPDIP package is convenient for prototype front-panel designs and through-hole hand-soldered prototype PCBs.
Recommended
Industrial Sensor Conditioning
In factory automation and process-control loops, the PIC18F27Q43-I/SP combines its 12-bit ADCC, 5-bit DAC, comparators, and CWG to form a complete analog front-end plus digital-control core. Six DMA channels keep ADC sample streams moving without CPU intervention, allowing deterministic sub-millisecond response for closed-loop control. Vectored interrupts with fixed three-instruction-cycle latency ensure predictable servicing of high-speed sensor events. The IEC 61508 Functional Safety diagnostics library supports SIL 2/3 capable sensor signal paths, while the industrial -40C to +85C grade suits cabinet-mounted instrumentation.
Recommended
BLDC / PMSM Motor Control
Three 16-bit dual PWMs give the PIC18F27Q43-I/SP six PWM outputs - exactly the count needed for six-step or FOC commutation of small three-phase BLDC and PMSM motors. The CWG (Complementary Waveform Generator) hardware inserts programmable dead-time automatically, preventing shoot-through in the half-bridge drivers. ADCC samples back-EMF and current sense resistors synchronously with the PWM period for high-bandwidth torque control. The 64 MHz CPU performs commutation math, while DMA offloads peripheral servicing for low-jitter operation across the full 0-50,000 RPM range.
Recommended
White-Goods and HVAC Control
Washing machines, dishwashers, refrigerators, and HVAC blowers benefit from the PIC18F27Q43-I/SP's combination of Functional Safety diagnostics, multiple PWMs for variable-speed motor and heater drive, and the CLC for hardware-state-machine logic that simplifies safety interlocks. The 28-SPDIP through-hole package is well-suited to appliances where hand-rework and field-serviceability are valued over SMT density. The XLP deep-sleep modes (down to sub-microamp) extend battery life in HVAC thermostats and wireless leak detectors paired with the same family.
Recommended
LED Lighting Driver with Smooth Dimming
The PIC18F27Q43-I/SP drives high-resolution LED dimming using its 16-bit PWMs and CLC-based LED-effect engines, achieving 0.1% dimming steps that exceed the human eye's perception threshold. ADCC reads ambient light sensors and feedback photodiodes for closed-loop constant-luminance control, while CWG generates complementary high-frequency FET drive waveforms with hardware dead-time. The 5-bit DAC provides an analog reference for constant-current driver ICs. XLP sleep currents in the microamp range suit battery-powered and solar-recharged architectural lighting fixtures.
Recommended
Battery-Powered IoT Edge Sensor
Battery-powered wireless sensor nodes benefit from the PIC18F27Q43-I/SP's XLP extreme-low-power modes (down to ~50 nA in sleep with RTCC, ~200 nA in sleep with ADC) and DMA-driven wake-on-event sampling. The 12-bit ADCC oversamples with hardware averaging for noise-immune readings from thermocouples, strain gauges, and electrochemical gas sensors, while the 64 MHz CPU runs LoRa/BLE stack preparation between long sleeps. Industrial temperature grade and 128 KB Flash accommodate OTA-bootloader stacks with margin for application logic.
Recommended
Functional Safety Sensor Module
Industrial safety functions - over-temperature cutoffs, gas-leak detection, motor-overspeed monitoring, and SIL-classified sensor paths - leverage the PIC18F27Q43-I/SP's integrated Functional Safety (FuSa) hardware diagnostics library. The library provides pre-verified test routines for the CPU, Flash, RAM, clock, and ADC, dramatically reducing the work to certify designs to IEC 61508 SIL 2/3. Six DMA channels, vectored interrupts with fixed three-cycle latency, and the dual-window watchdog (WWDT) underpin deterministic safety response. The 28-SPDIP through-hole package also simplifies field-replaceable safety-module serviceability.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F27Q43-I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F27Q43-E/SP | PIC18F25Q43-I/SP | PIC18F26Q43-I/SP | PIC18F27Q43-E/SPB19 |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SPDIP | 28-SPDIP - same | 28-SPDIP - same | 28-SPDIP - same | 28-SPDIP - same |
| Flash Memory | 128 KB | 128 KB | 64 KB (-50%) | 64 KB (-50%) | 128 KB |
| RAM | 8 KB | 8 KB | 8 KB | 8 KB | 8 KB |
| CPU Speed | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +85C | -40C to +125C |
| Functional Safety (FuSa) | Yes (IEC 61508 SIL 2/3 library) | Yes | Yes | Yes | Yes |
| DMA Controllers | 6 | 6 | 6 | 6 | 6 |
| Approx Unit Price @ 1000pcs (as of 2026-09-27) | ~$2.46 | ~$2.55 | ~$2.20 | ~$2.30 | ~$2.55 |
Key Differentiators
- Higher Flash density in same 28-pin package (vs PIC18F25Q43-I/SP)
- Industrial temperature range variant available (vs PIC18F27Q43-I/SP (standard -40C to +85C))
- Functional Safety diagnostics library integrated (vs PIC18F27K42-I/SP (previous-gen K42 without FuSa))
- Six independent DMA channels (vs PIC18F26K83-I/SP (no DMA in K83))
- Three 16-bit dual PWMs (six outputs) (vs PIC18F27J13-I/SS (limited PWM channels))
Design Notes
The PIC18F27Q43-I/SP accepts VDD from 1.8 V to 5.5 V, but the 64 MHz FOSC maximum derates to lower values at VDD below 2.7 V per the electrical-characteristics table. Place a 100 nF decoupling capacitor on each VDD pin pair (10/11 and 20/21) within 2 mm of the package, plus a bulk 10 uF tantalum or ceramic close to the regulator. For sleep-mode applications, switching off the MCU's BOR (Brown-Out Reset) at low VDD further reduces quiescent current below 50 nA.
The 28-SPDIP package has a theta_JA around 50-60 C/W in still air - adequate for the PIC18F27Q43's typical 15-20 mA active current (about 50-100 mW at 5 V), so no heatsink is required. However, in enclosed industrial housings at 60-70 C ambient, junction temperatures can rise close to 100 C. For derated designs use the SO/SS surface-mount variants which spread heat better and are recommended for reflow assembly lines.
Route ICSP pins RB6/ICSPCLK and RB7/ICSPDAT to a 6-pin header (or test points) with VPP/MCLR, VDD, and VSS for in-circuit programming and debugging. Keep the ICSP trace length below 50 mm and avoid routing them adjacent to switching nodes or PWM outputs to minimize programming glitches. Reserve space for a 32.768 kHz crystal on SOSC0/SOSCO (RB4/RB5 with PPS) if RTCC-based sleep timing is required.
PWM outputs are 5 V CMOS at full drive; high-current PWM traces (>10 mA load) should be at least 0.2 mm wide with a ground pour underneath. Place the MCU bypass caps on the same side as the IC, never on the opposite PCB side. For ADCC accuracy, route analog inputs as short differential pairs surrounded by analog ground, and avoid crossing digital signal traces to prevent capacitive coupling noise.
Estimated: the PIC18F27Q43's MCLR pin is bidirectional - it can act as a reset input AND output. When using it as an output in a multi-MCU system, add a 1-10 kohm pull-up to VDD. Configuration words (CONFIG1-5) MUST be set before code execution; an incorrect oscillator or WDT setting can lock the device. Always define the unused I/O pins as outputs with low level to minimize current draw, and avoid floating analog inputs to prevent ADC drift.
Compliance Information
RoHS and REACH compliance confirmed per Microchip product page. Industrial temperature grade - not AEC-Q100 qualified; for AEC-Q100 use automotive-qualified -VAO/-SP variants. IEC 61508 SIL 2/3 Functional Safety library is a hardware diagnostics asset, not an automotive qualification.
