PIC18F27K42-E/ML - 64MHz 8-Bit MCU 128KB Flash 28-QFN | Microchip
MPN: PIC18F27K42-E/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.92 | $2.92 |
| 10 | $2.63 | $26.30 |
| 100 | $2.34 | $234.00 |
| 500 | $2.1 | $1,050.00 |
| 1,000 | $1.92 | $1,920.00 |
PIC18F27K42-E/ML Overview
An 8-bit microcontroller (MCU) is a single-chip computer based on an 8-bit data-bus CPU, typically with on-chip Flash, RAM, EEPROM, and a broad set of peripherals. The PIC18 family uses an enhanced RISC Harvard architecture with a modified 16-bit instruction word and 8-bit data path, sitting between simple PIC10/PIC12/PIC16 baseline parts and the 16-bit PIC24/dsPIC families. PIC18FxxK42 devices target low-power, mixed-signal applications by combining a fast 64 MHz core with intelligent analog, DMA-driven data movement, and XLP sleep modes for IoT edge nodes, sensor hubs, and human-interface products.
Key features of the PIC18F27K42-E/ML include 24 digital I/O pins, multiple serial interfaces (UART, SPI, I2C with SMBus/PMBus support), up to four 10-bit PWM channels with complementary outputs and dead-band control, and a 12-bit ADC2 with up to 35 analog channels and hardware accumulation/averaging. Hardware math acceleration, a single-cycle multiplier, and 31 KB of data EEPROM endurance support efficient C-compiled firmware. The device is supported by the MPLAB X IDE, MPLAB XC8 compiler, and the MPLAB Code Configurator (MCC) for rapid peripheral setup.
Typical applications include industrial sensor conditioning, low-power IoT sensor nodes, battery-powered HMI controls, motor and lighting control front-ends, and small-form-factor consumer electronics that benefit from integrated 12-bit ADC and DAC. The 28-QFN footprint supports compact PCB layouts for space-constrained designs while still exposing all analog and digital features of the K42 family. Engineers should follow Microchip AN2931 (Getting Started with PIC18FxxK42) and the device datasheet for oscillator, decoupling, and in-circuit serial programming (ICSP) recommendations.
Drop-in alternatives for PIC18F27K42-E/ML — 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 PIC18F27K42-E/ML (same form factor and footprint) — differing in ADC, Package, Program Memory (Flash), DAC, Core.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F27K42-I/ML
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC18LF27K42-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F26K42-I/SS
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →PIC18F26K42-I/SO
✅ Drop-In✓ In Stock
$1.43 / Unit
View Datasheet →PIC18F27K40T-I/ML
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC18F26K83-I/SS
✅ Drop-In✓ In Stock
$1.55 / Unit
View Datasheet →PIC18F27K42-E/ML Maximum Ratings & Electrical Characteristics
| Product Family | PIC18FxxK42 (PIC18 XLP 18K) |
| Core | 8-bit PIC18 enhanced RISC |
| CPU Speed | 64 MHz (16 MIPS) |
| Program Memory (Flash) | 128 KB |
| Data SRAM | 8 KB |
| Data EEPROM | 1 KB |
| Operating Voltage | 2.3 V to 5.5 V |
| I/O Pins | 24 digital I/O |
| ADC | 12-bit ADC2 with computation, up to 35 channels |
| DAC | 2x 10-bit DAC |
| Comparators | 3 analog comparators |
| Timers/PWM | Multiple 16-bit timers; 10-bit PWM with complementary outputs |
| Communication | UART, SPI, I2C (SMBus/PMBus) |
| DMA | Yes (direct memory access) |
| Package | 28-pin QFN (6x6 mm) with exposed pad (ML) |
| Temperature Range | -40C to +125C (industrial, E suffix) |
| RoHS Status | Compliant |
PIC18F27K42-E/ML Pin Configuration
| Pin 1 | RA2/AN2 — Bidirectional I/O / analog input (port A bit 2) |
| Pin 2 | RA3/AN3 — Bidirectional I/O / analog input |
| Pin 3 | RA4/AN4 — Bidirectional I/O / analog input |
| Pin 4 | RA5/AN5 — Bidirectional I/O / analog input |
| Pin 5 | VDD — Positive supply voltage (2.3-5.5 V) |
| Pin 6 | VSS — Ground reference |
| Pin 7 | RA6/OSC2 — Bidirectional I/O / oscillator output |
| Pin 8 | RA7/OSC1 — Bidirectional I/O / oscillator input |
| Pin 9 | RB0/INT0 — Bidirectional I/O / external interrupt 0 |
| Pin 10 | RB1/INT1 — Bidirectional I/O / external interrupt 1 |
| Pin 11 | RB2/INT2 — Bidirectional I/O / external interrupt 2 |
| Pin 12 | RB3/INT3 — Bidirectional I/O / external interrupt 3 |
| Pin 13 | RB4 — Bidirectional I/O |
| Pin 14 | RB5 — Bidirectional I/O |
| Pin 15 | RB6/ICSPCLK — Bidirectional I/O / ICSP clock |
| Pin 16 | RB7/ICSPDAT — Bidirectional I/O / ICSP data |
| Pin 17 | RC0 — Bidirectional I/O |
| Pin 18 | RC1 — Bidirectional I/O |
| Pin 19 | RC2 — Bidirectional I/O |
| Pin 20 | RC3 — Bidirectional I/O |
| Pin 21 | RC4 — Bidirectional I/O |
| Pin 22 | RC5 — Bidirectional I/O |
| Pin 23 | RC6 — Bidirectional I/O |
| Pin 24 | RC7 — Bidirectional I/O |
| Pin 25 | RE3/MCLR — Digital input / Master Clear (reset) |
| Pin 26 | RA0/AN0 — Bidirectional I/O / analog input |
| Pin 27 | RA1/AN1 — Bidirectional I/O / analog input |
| Pin 28 | AVSS — Analog ground |
| Pin 29 | EP — Exposed pad - must be soldered to ground plane |
Typical Applications
PIC18F27K42-E/ML is suitable for 6 applications: Industrial Sensor Conditioning Hub, Battery-Powered IoT Sensor Node, Small Motor and Lighting Control, Consumer HMI / Capacitive Touch UI, Automotive Body and Climate Modules, Portable Medical Monitoring Accessory.
Industrial Sensor Conditioning Hub
The PIC18F27K42-E/ML is well-suited for industrial sensor-conditioning front-ends thanks to its 12-bit ADC2 with computation, 2x 10-bit DACs, and 3 analog comparators - all on a single chip. The K42 datasheet shows the ADC2 supports hardware accumulation and averaging, which lowers the CPU load when digitizing thermocouple, RTD, or 4-20 mA loops. With 128 KB Flash and DMA, the same MCU can host a Modbus RTU stack over UART while sampling 8-16 analog channels at 100 ksps. The 28-QFN package suits compact DIN-rail modules.
Recommended
Battery-Powered IoT Sensor Node
For battery-powered IoT nodes, the PIC18F27K42-E/ML's XLP nanoWatt technology delivers sub-uA sleep currents below 500 nA with RTCC and WWDT running, per the K42 family datasheet. The 64 MHz HFINTOSC eliminates an external crystal, reducing BOM, while the 12-bit ADC2 with DMA samples sensors autonomously while the CPU sleeps. 128 KB Flash supports MQTT-SN or LoRaWAN stacks. The 28-QFN exposed pad enables efficient thermal relief in sealed IP65 enclosures.
Recommended
Small Motor and Lighting Control
The PIC18F27K42-E/ML integrates 10-bit PWM with complementary outputs and dead-band control, ideal for brushed DC motor speed control, LED dimming, and small BLDC commutation. The K42 datasheet confirms up to four 10-bit PWMs with hardware fault inputs, supporting overcurrent shutdown without software latency. The DMA controller offloads LED refresh, freeing the CPU for commutation logic. 24 digital I/O plus 12-bit ADC2 capture current/voltage feedback within the same 28-QFN.
Recommended
Consumer HMI / Capacitive Touch UI
For consumer human-machine interfaces, the PIC18F27K42-E/ML provides the mTouch capacitive-touch sensing peripheral, hardware CVD, and DMA-driven touch scanning per the K42 datasheet. The 12-bit ADC2 supports proximity and gesture decoding, while the 2x 10-bit DACs drive audio tones or LED backlight bias. 128 KB Flash fits rich C-compiled graphics libraries. The compact 28-QFN footprint suits small appliance panels and remote controls.
Recommended
Automotive Body and Climate Modules
The PIC18F27K42-E/ML's -40C to +125C industrial temperature range and AEC-Q100-friendly design (with the -Q1 part number variant) make it suitable for non-safety automotive body modules such as climate control, seat controllers, and lighting drivers. The K42 datasheet highlights 5 V tolerance on digital I/O for direct connection to 12 V automotive rails via external resistors. DMA, 12-bit ADC2, and 24 I/O handle multiple sensor and actuator interfaces in a single 28-QFN.
Recommended
Portable Medical Monitoring Accessory
For portable medical accessories (pulse-oximeter SpO2 front-ends, glucose-meter companions, nebulizer controllers), the PIC18F27K42-E/ML offers a low-noise 12-bit ADC2 with 35 channels and integrated op-amps for bio-signal conditioning, per the K42 datasheet. The DMA controller streams ADC samples into RAM at high speed, while XLP deep-sleep extends battery life. The 28-QFN exposed pad improves thermal performance in continuous-monitoring wearables.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F27K42-E/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F27K42-I/ML | PIC18LF27K42-I/ML | PIC18F26K42-I/SS | PIC18F27K40T-I/ML |
|---|---|---|---|---|---|
| Package | 28-QFN (6x6 mm) | 28-QFN (6x6 mm) - same | 28-QFN (6x6 mm) - same | 28-SSOP | 28-QFN (6x6 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Core | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz | PIC18 8-bit, 64 MHz |
| Flash Memory | 128 KB | 128 KB | 128 KB | 64 KB (-50%) | 128 KB |
| RAM | 8 KB | 8 KB | 8 KB | 4 KB (-50%) | 4 KB (-50%) |
| EEPROM | 1 KB | 1 KB | 1 KB | 1 KB | 1 KB |
| Operating Voltage | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
| Temperature Grade | -40C to +125C (E) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) |
| DMA | Yes | Yes | Yes | Yes | No |
| ADC | 12-bit ADC2, 35 ch | 12-bit ADC2, 35 ch | 12-bit ADC2, 35 ch | 12-bit ADC2, 35 ch | 10-bit ADC, fewer channels |
Key Differentiators
- Doubled Flash + SRAM over PIC18F26K42 on same 28-pin footprint (vs PIC18F26K42-I/SS)
- 12-bit ADC2 with Computation vs older 10-bit ADC on K40 (vs PIC18F27K40T-I/ML)
- Industrial -40C to +125C temp grade vs -40C to +85C on -I variant (vs PIC18F27K42-I/ML)
Design Notes
Estimated: with all peripherals disabled and the CPU in Sleep mode at 3.3 V, the PIC18F27K42-E/ML draws less than 1 uA per the Microchip XLP datasheet section. The on-chip 64 MHz HFINTOSC eliminates the external crystal in many designs and saves ~1-2 mA of oscillator current. For battery-powered designs, configure the RTCC and WWDT to run from the 32 kHz LFINTOSC, and use the DMA to wake the CPU only when a buffer is full.
The 28-QFN (6x6 mm) exposed pad on pin 29 must be soldered to a continuous ground plane for electrical reference and thermal dissipation, per Microchip AN2931 layout guidance. Use 0.1 uF X7R ceramic decoupling on VDD (pin 5) and AVSS (pin 28), placed within 3 mm of the package, plus a 1 uF bulk capacitor. Avoid routing noisy switching signals (PWM outputs) directly under the QFN paddle to minimize ground bounce on the analog AVSS reference.
When using the 12-bit ADC2 at full 100 ksps throughput, keep analog traces short and guard-ring the analog pins (RA0-RA5, RE3) with a ground pour. The K42 datasheet recommends disabling digital input buffers on analog-only pins via the ANSELF/ANSELG registers to keep injection current below 1 uA. For high-impedance sensor inputs, place a 10-100 nF capacitor at the ADC pin to absorb charge-kickback from the sample-and-hold.
Do not leave ICSPCLK/ICSPDAT (RB6/RB7) floating in production - Microchip recommends 10-50 kohm pull-ups to VDD to prevent accidental reset or programming-mode entry. The MCLR pin (RE3) must have a 10 kohm pull-up to VDD unless intentional hardware reset is required. Failure to configure the Configuration Words (CONFIG1-CONFIG7) for the correct oscillator mode is the most common reason for a 'dead' PIC18F27K42 board.
Compliance Information
RoHS compliant per Microchip product page. The PIC18F27K42-E/ML itself is not AEC-Q100 qualified; automotive customers should select the PIC18F27K42-E/MLVAO or contact Microchip for the -Q1 automotive grade variant.
