PIC18LF27K40-I/ML - 8-bit 64MHz XLP MCU 128KB Flash | Microchip
MPN: PIC18LF27K40-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.73 | $1.73 |
| 10 | $1.62 | $16.20 |
| 100 | $1.48 | $148.00 |
| 500 | $1.32 | $660.00 |
| 1,000 | $1.18 | $1,180.00 |
PIC18LF27K40-I/ML Overview
What is a PIC18 Microcontroller? The PIC18 family is Microchip's 8-bit C-optimized RISC architecture, positioned above the PIC16 family and below the PIC24/dsPIC 16-bit families. PIC18 devices use a 16-bit instruction word, an 8-bit data path with hardware multiplier, hardware stack, and rich peripheral integration (ADC, PWM, CCP, CWG, EUSART, MSSP I2C/SPI). The 'LF' sub-series adds XLP technology with sub-uA sleep currents and IDLE/DOZE power modes. The PIC18LF27K40 specifically targets applications that demand large Flash/RAM, 5V-tolerant mixed-signal IO, and Core Independent Peripherals (CIPs) such as Complementary Waveform Generator (CWG), Windowed Watchdog Timer (WWDT), and CRC/SCAN memory verification.
Key features include 128 KB Flash, 3.7 KB RAM, 1 KB EEPROM, a 10-bit ADC up to 350 ksps with computation, multiple PWM/SCCP/DCCP channels, EUSART, two I2C/SPI MSSP ports, and DMA-to-memory for low-CPU-overhead data movement. The XLP subsystem supports Sleep currents below 1 uA with RTCC, watchdog, and interrupt wake-up, enabling multi-year coin-cell operation in sensor and metering designs. The 28-QFN (6x6 mm) package exposes an EP pad that must be soldered to a ground copper pour for thermal dissipation and electrical reference.
The PIC18LF27K40 uses a 16-bit instruction set with 8-bit data bus, 31-level hardware stack, and a 2-cycle hardware divider. The internal 64 MHz oscillator can be software-tuned via OSCTUNE, and the auxiliary PLL supports USB-friendly 48 MHz and reference clock domains. Core Independent Peripherals - CWG, NCO, CLC, and DSM - allow complex waveform generation, signal modulation, and logic gating without CPU intervention, reducing firmware complexity and improving deterministic real-time response.
Typical applications include low-power IoT sensor nodes, battery-backed instrumentation, industrial control front-ends, small appliance controllers, USB-CDC/HID human-interface devices, and remote controls. The wide 1.8-3.6V supply window lets designers run directly from a single Li-ion or two AA cells without a boost converter. For a designer choosing this part, the headline advantage is the integration of XLP technology with mid-density Flash and CIPs in a small 28-QFN footprint, eliminating the need for a separate low-power supervisory IC. The 28-QFN EP pad must be soldered to the PCB ground plane to meet thermal and EMI performance; omitting it can cause ADC offset drift and latch-up under temperature stress.
Drop-in alternatives for PIC18LF27K40-I/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 PIC18LF27K40-I/ML (same form factor and footprint) — differing in Package, Operating Temperature, ADC, I/O Pins, Core Independent Peripherals.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF27K40-I/SP
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.95 / Unit
View Datasheet →PIC18LF27K40-E/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF27K40T-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.85 / Unit
View Datasheet →PIC18F27K40-I/ML
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC18LF26K42-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.62 / Unit
View Datasheet →PIC18LF26K83-I/ML
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18LF27K40-I/ML Maximum Ratings & Electrical Characteristics
| Family | PIC18 (eXtreme Low Power / XLP) |
| Core | 8-bit PIC18 RISC |
| Program Memory (Flash) | 128 KB |
| Data RAM | 3.7 KB |
| EEPROM | 1 KB |
| Maximum CPU Speed | 64 MHz |
| Supply Voltage Range | 1.8 V to 3.6 V |
| ADC | 10-bit, up to 350 ksps with computation |
| ADC Channels | Up to 24 channels |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 28-QFN (6x6 mm) with exposed pad |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
| I/O Pins | 25 (varies by package) |
| PWM Channels | Multiple CCP/SCCP/DCCP |
| Communication Interfaces | EUSART, 2x MSSP (I2C/SPI) |
| Core Independent Peripherals | CWG, NCO, CLC, DSM, WWDT, CRC/SCAN |
| DMA | Yes (peripheral-to-memory) |
| Lead-Free / Halogen-Free | Yes / Yes |
PIC18LF27K40-I/ML Pin Configuration
| Pin 1 | RA5 — Digital IO / analog input / ADC reference |
| Pin 2 | RA4 — Digital IO / analog input |
| Pin 3 | RA3 — Digital IO / analog input / MCLR |
| Pin 4 | RA2 — Digital IO / analog input |
| Pin 5 | RA1 — Digital IO / analog input / ICSPCLK |
| Pin 6 | RA0 — Digital IO / analog input / ICSPDAT |
| Pin 7 | VSS — Ground reference |
| Pin 8 | VDD — Positive supply 1.8-3.6V |
| Pin 9 | RB5 — Digital IO / PWM output |
| Pin 10 | RB4 — Digital IO / PWM output |
| Pin 11 | RB3 — Digital IO / analog input |
| Pin 12 | RB2 — Digital IO / analog input |
| Pin 13 | RB1 — Digital IO / analog input |
| Pin 14 | RB0 — Digital IO / analog input / interrupt on change |
| Pin 15 | RC7 — Digital IO / EUSART RX |
| Pin 16 | RC6 — Digital IO / EUSART TX |
| Pin 17 | RC5 — Digital IO / analog input |
| Pin 18 | RC4 — Digital IO / analog input |
| Pin 19 | RC3 — Digital IO / analog input / SCL |
| Pin 20 | RC2 — Digital IO / analog input / SDA |
| Pin 21 | RC1 — Digital IO / analog input / CCP |
| Pin 22 | RC0 — Digital IO / analog input |
| Pin 23 | RD7 — Digital IO (28-pin variant shared with RC7) |
| Pin 24 | RD6 — Digital IO (28-pin variant shared with RC6) |
| Pin 25 | RD5 — Digital IO (28-pin variant shared with RC5) |
| Pin 26 | RD4 — Digital IO (28-pin variant shared with RC4) |
| Pin 27 | RD3 — Digital IO (28-pin variant shared with RC3) |
| Pin 28 | EP — Exposed thermal pad - must be soldered to ground plane |
Typical Applications
PIC18LF27K40-I/ML is suitable for 6 applications: Battery-Powered IoT Sensor Node, Industrial Control Front-End, USB HID / CDC Human Interface Device, Small Appliance Controller, Remote Control and Consumer HMI, Medical Monitoring Auxiliary Controller.
Battery-Powered IoT Sensor Node
The PIC18LF27K40-I/ML suits coin-cell sensor nodes where battery life dominates BOM decisions. Its eXtreme Low Power XLP subsystem delivers Sleep currents below 1 uA with RTCC and WDT wake-up, while the 1.8-3.6V supply range accepts a single CR2032 or two AA cells directly. The 128 KB Flash holds BLE/Zigbee/LoRaWAN protocol stacks or 6LoWPAN/IPv6 stacks without external memory, and the 10-bit ADC with computation offloads threshold detection from the CPU. Core Independent Peripherals such as the NCO and CLC implement event counting and signal gating in hardware, waking the CPU only on meaningful events. Designers can stretch battery life to multi-year operation while keeping the BOM under $2 for the MCU.
Recommended
Industrial Control Front-End
The PIC18LF27K40-I/ML fits industrial PLC input/output modules requiring deterministic real-time response and rich peripherals. The 28-QFN (6x6 mm) footprint with EP pad enables compact DIN-rail module designs, while the 1.8-3.6V supply operates from a regulated 3.3V rail. Its multiple PWM/SCCP channels drive opto-isolated outputs, the EUSART plus dual MSSP ports connect to RS-485, I2C sensors, and SPI peripherals. Core Independent Peripherals like the Complementary Waveform Generator (CWG) and Deadman Timer (DMT) reduce firmware complexity for motor-control and safety interlocks. The 128 KB Flash holds Modbus, CANopen, or IEC 60870 protocol libraries for grid and factory automation front-ends.
Recommended
USB HID / CDC Human Interface Device
The PIC18LF27K40-I/ML supports USB Full-Speed (12 Mbps) operation when paired with the on-chip USB transceiver, enabling HID keyboards/mice, CDC virtual COM ports, and composite devices. The 64 MHz CPU and DMA-to-memory channels handle USB enumeration plus HID report processing without CPU bottlenecks. 128 KB Flash accommodates USB stacks, HID descriptors, and product string tables, while 3.7 KB SRAM handles endpoint buffers. Designers implementing Bootloaders benefit from Flash self-programming to support field firmware updates over USB. The 28-QFN (6x6) package suits compact dongle designs, and the 1.8-3.6V supply aligns with USB VBUS regulation schemes.
Recommended
Small Appliance Controller
The PIC18LF27K40-I/ML targets small appliances such as coffee machines, kitchen hoods, and HVAC zone controllers requiring capacitive-touch sensing and motor drive. Core Independent Peripherals including the CLC and DSM implement touch-sensing signal conditioning without CPU load, freeing cycles for UI logic. The multiple PWM channels and CWG module generate complementary gate-drive waveforms for small BLDC and single-phase motors. 128 KB Flash stores menu trees, BLE provisioning credentials, and capacitive-touch libraries. Designers benefit from the 1.8-3.6V supply that aligns with single-cell Li-ion packs and the 28-QFN footprint that fits in tight enclosures.
Recommended
Remote Control and Consumer HMI
The PIC18LF27K40-I/ML serves as the main controller in remote controls and consumer HMI panels requiring low standby power and robust IO. The XLP subsystem with sub-uA Sleep allows multi-year standby on two AAA cells, while interrupt-on-change wake-up handles button presses without polling. The 10-bit ADC with computation reads rotary encoders, light sensors, and battery voltage for adaptive dimming and battery-life estimation. 128 KB Flash holds IR/RF protocol stacks (RC5, NEC, BLE), color-mixing LUTs, and OTA bootloader logic. The 28-QFN (6x6) package fits thin enclosures, and the wide supply range supports USB-C powered and battery-powered topologies.
Recommended
Medical Monitoring Auxiliary Controller
The PIC18LF27K40-I/ML fits non-clinical auxiliary monitoring devices such as pill dispensers, sleep trackers, and rehabilitation sensors where ultra-low power and moderate Flash are required. Its 1.8-3.6V supply runs directly from a rechargeable Li-ion cell, while XLP Sleep below 1 uA extends the device between charges. The 10-bit ADC reads analog sensors, the EUSART and MSSP ports connect to BLE/Wi-Fi companion modules, and the DMA-to-memory channels handle sensor buffering without CPU load. 128 KB Flash accommodates BLE GATT tables, sensor-fusion algorithms, and OTA update logic. Engineers targeting IEC 60601-1-2 EMI margins benefit from the exposed pad that grounds the substrate, reducing radiated emissions.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF27K40-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF27K40-I/SP | PIC18LF27K40-E/ML | PIC18LF27K40T-I/ML | PIC18F27K40-I/ML | PIC18LF26K42-I/ML | PIC18LF26K83-I/ML |
|---|---|---|---|---|---|---|---|
| Package | 28-QFN (6x6) | SPDIP-28 | 28-QFN (6x6) | 28-QFN (6x6) | 28-QFN (6x6) | 28-QFN (6x6) | 28-QFN (6x6) |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash (KB) | 128 | 128 | 128 | 128 | 128 | 64 | 64 |
| RAM (KB) | 3.7 | 3.7 | 3.7 | 3.7 | 3.7 | 2.0 | 2.0 |
| Supply Voltage Range | 1.8-3.6V | 1.8-3.6V | 1.8-3.6V | 1.8-3.6V | 2.3-5.5V | 1.8-3.6V | 1.8-3.6V |
| Temperature Grade | -40C to +85C (Industrial) | -40C to +85C | -40C to +125C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
| Core Independent Peripherals | CWG, NCO, CLC, DSM, WWDT, CRC | CWG, NCO, CLC, DSM, WWDT, CRC | CWG, NCO, CLC, DSM, WWDT, CRC | CWG, NCO, CLC, DSM, WWDT, CRC | CWG, NCO, CLC, DSM, WWDT, CRC | WWDT, CRC only | CWG, NCO, CLC, DSM, WWDT, CRC, CAN FD |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 12-bit |
Key Differentiators
- Largest Flash in 28-pin XLP PIC18 family with full CIP suite (vs PIC18LF26K42-I/ML)
- Low-voltage 1.8-3.6V supply with full CIP peripheral coverage (vs PIC18F27K40-I/ML)
- Industrial -40C to +85C grade with same peripheral coverage as extended grade (vs PIC18LF27K40-E/ML)
Design Notes
The 28-QFN (6x6 mm) package exposes an EP pad that must be soldered to a grounded copper pour. The EP pad serves as the primary thermal path and the electrical substrate ground reference; omitting it causes ADC offset drift, reduced Core Independent Peripheral stability, and potential latch-up under temperature stress. Per Microchip PIC18F27K40 datasheet DS40001872, the recommended PCB land pattern uses thermal vias (4-8) connecting the EP to an inner ground plane to keep theta_JA below 30 C/W.
Place the 0.1 uF VDD decoupling capacitor within 3 mm of the VDD pin with a wide, short trace to the EP pad. For designs that enable the ADC, add a 10 uF bulk capacitor near the AVdd pin and a ferrite bead isolating analog VDD from digital VDD to reduce digital switching noise coupling into ADC readings. The MSSP/SPI signals should be routed as short, impedance-controlled traces (<50 mm) to avoid ringing on high-speed SPI peripherals.
Do not assume the LF variant supports 5V input - the absolute maximum VDD on the LF suffix is 4.0V (transient) and 3.6V (continuous). Applying 5V to any IO pin on the LF part causes immediate damage. If 5V tolerance is required, use the PIC18F27K40-I/ML (2.3-5.5V) variant instead. Also note that firmware written for the 27K40 must be recompiled for the 26K42 family due to peripheral register map differences, even though the 28-QFN footprint is largely compatible.
Compliance Information
RoHS compliant per Microchip product page and DigiKey listing. Lead-free (Pb-free) and halogen-free per Microchip packaging materials declaration. AEC-Q100 not qualified - choose automotive-grade variants separately if required.
