PIC18LF27K40-E/SP - 8-bit 64MHz 128KB Flash XLP MCU | Microchip
MPN: PIC18LF27K40-E/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.52 | $3.52 |
| 10 | $3.17 | $31.70 |
| 100 | $2.51 | $251.00 |
| 500 | $2.18 | $1,090.00 |
| 1,000 | $1.93 | $1,930.00 |
PIC18LF27K40-E/SP Overview
An 8-bit PIC microcontroller is a Harvard-architecture RISC CPU with separate program and data buses, on-chip Flash for code storage, integrated peripherals, and a 16-bit instruction set designed for deterministic real-time control. PIC18F/K devices sit in the middle of Microchip's 8-bit MCU portfolio - more capable than PIC10/12/16 baseline parts, simpler than PIC24/dsPIC 16-bit families. The PIC18 K-series ('K40') adds Core Independent Peripherals (CIPs): CWG, CCP, PWM, 10-bit ADC with Computation (ADC2), 5-bit DAC, comparators, zero-cross detect (ZCD), CRC/SCAN, and a windowed watchdog (WWDT) that offload timing-critical tasks from the CPU and reduce firmware complexity.
Key features include the eXtreme Low Power (XLP) picoPower core with deep sleep currents down to the 50 nA range, an integrated 32 kHz low-power RTCC oscillator, on-chip 32 MHz HFINTOSC with 0.25% calibration, a 24-channel 10-bit ADC, and configurable logic cell (CLC) blocks. The device supports up to 25 I/O pins with peripheral pin select (PPS) routing, plus SPI/I2C/UART with DMA-style buffer access. Programming is via ICSP and the device is supported by MPLAB X IDE, XC8 compilers, and the MPLAB Code Configurator (MCC) for graphical peripheral setup.
The architecture uses a pipelined 8-bit data path with a 16-bit instruction word and a hardware multiplier, giving 64 MHz throughput at 16 MIPS. Internal dual oscillators plus a 4x PLL eliminate many external crystals in cost-sensitive designs. The 'K40' family emphasizes deterministic I/O: every peripheral trigger can wake the CPU, run autonomously, and return to sleep without software intervention - useful in battery sensors that must sleep 99.9% of the time.
Typical applications include battery-powered IoT sensor nodes, smart metering, HVAC and thermostat controls, white-goods user modules, automotive body and lighting controllers (under-hood LIN nodes when paired with a transceiver), and USB-touch human-machine interface panels. The wide VDD range and extended temperature grade also suit industrial sensor transmitters and low-end motor-control subsystems using the CWG and CCP/PWM peripherals.
When designing with this MCU, route PPS carefully - peripherals can be remapped to most I/O, but only one function per pin at a time, and remap must match the schematic. Decouple VDD/VSS pairs with 100 nF plus bulk capacitance, place the 32.768 kHz crystal close to SOSCO/SOSCI pins when using RTCC, and budget at least 4 KB stack/heap above MCC-generated initialization. The E/SP package is also footprint-compatible with other PIC18F27K40 SPDIP variants, easing upgrade paths.
This page synthesizes distributor pricing, drop-in alternatives, design notes, and an AEO-optimized FAQ drawn from the Microchip PIC18(L)F27/47K40 datasheet and live distributor listings - not a copy of the manufacturer PDF.
Drop-in alternatives for PIC18LF27K40-E/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 PIC18LF27K40-E/SP (same form factor and footprint) — differing in Package, ADC, Comparators, DAC, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F27K40-E/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF27K40-I/SP
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC18LF26K40-E/SP
✅ Drop-In✓ In Stock
$1.85 / Unit
View Datasheet →PIC18LF25K40-E/SP
✅ Drop-In✓ In Stock
$2 / Unit
View Datasheet →PIC18LF27K40-E/SO
✅ Drop-In✓ In Stock
$1.86 / Unit
View Datasheet →PIC18LF27K40-E/SP Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Instruction Set | 16-bit C-optimized |
| Max CPU Frequency | 64 MHz (16 MIPS) |
| Program Memory (Flash) | 128 KB (64K x 16) |
| Data RAM | 4 KB |
| Data EEPROM | 256 B |
| Operating Voltage Range | 1.8 V to 3.6 V (LF variant) |
| Operating Temperature Range | -40 C to +125 C (E suffix) |
| ADC | 10-bit ADC2, up to 24 channels |
| DAC | 5-bit, 1 channel |
| Comparators | Yes (on-chip) |
| PWM / CCP / CWG | PWM + CCP + CWG (Complementary Waveform Generator) |
| Windowed Watchdog (WWDT) | Yes |
| CRC / SCAN | Yes |
| ZCD (Zero-Cross Detect) | Yes |
| Communication Peripherals | UART, SPI, I2C with PPS |
| I/O Pins | Up to 25 |
| Low-Power Technology | XLP (eXtreme Low Power) picoPower |
| Package | 28-pin SPDIP (SP) - through-hole |
| RoHS Status | Compliant |
PIC18LF27K40-E/SP Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (reset) input / digital input only on PORTE bit 3 |
| Pin 2 | RA0 — Digital I/O / analog input AN0 |
| Pin 3 | RA1 — Digital I/O / analog input AN1 |
| Pin 4 | RA2 — Digital I/O / analog input AN2 / DAC output |
| Pin 5 | RA3 — Digital I/O / analog input AN3 / reference voltage |
| Pin 6 | RA4 — Digital I/O / analog input AN4 |
| Pin 7 | RA5 — Digital I/O / analog input AN5 |
| Pin 8 | VSS — Ground reference |
| Pin 9 | RA7 — Digital I/O / oscillator input |
| Pin 10 | RA6 — Digital I/O / oscillator output |
| Pin 11 | VDD — Positive supply voltage (1.8V-3.6V) |
| Pin 12 | VSS — Ground reference |
| Pin 13 | RB0 — Digital I/O / interrupt-on-change |
| Pin 14 | RB1 — Digital I/O / interrupt-on-change |
| Pin 15 | RB2 — Digital I/O / interrupt-on-change |
| Pin 16 | RB3 — Digital I/O / interrupt-on-change |
| Pin 17 | RB4 — Digital I/O / interrupt-on-change |
| Pin 18 | RB5 — Digital I/O / interrupt-on-change |
| Pin 19 | RB6 — Digital I/O / ICSPCLK programming clock |
| Pin 20 | RB7 — Digital I/O / ICSPDAT programming data |
| Pin 21 | RC0 — Digital I/O / analog input AN6 |
| Pin 22 | RC1 — Digital I/O / analog input AN7 |
| Pin 23 | RC2 — Digital I/O / analog input AN8 |
| Pin 24 | RC3 — Digital I/O / analog input AN9 |
| Pin 25 | RC4 — Digital I/O |
| Pin 26 | RC5 — Digital I/O |
| Pin 27 | RC6 — Digital I/O |
| Pin 28 | RC7 — Digital I/O |
Typical Applications
PIC18LF27K40-E/SP is suitable for 6 applications: Battery-Powered IoT Sensor Nodes, Industrial Sensor Transmitters (4-20 mA / Modbus), HVAC and Thermostat Controls, Automotive Body and Lighting Nodes, Smart Metering (Water / Heat / Gas), White Goods and Consumer Appliance Control.
Battery-Powered IoT Sensor Nodes
The PIC18LF27K40-E/SP fits battery-powered IoT sensor nodes because its XLP picoPower core draws less than 50 nA in deep sleep with RTCC running, waking only on a peripheral interrupt. The 1.8-3.6 V VDD range supports direct connection to single-cell Li-ion or 2xAA chemistries without a boost regulator. The 24-channel 10-bit ADC2 with computation offloads averaging and threshold detection from the CPU, while the 128 KB Flash holds LoRaWAN, BLE through-sPI, or Zigbee stacks with margin for OTA bootloaders. UART/SPI/I2C with PPS maps the radio and sensor to any convenient pin, simplifying two-layer PCB layout for sub-1 GHz or 2.4 GHz radio modules. Compared with ARM Cortex-M0+ parts at the same price, the K40 trades raw MHz for deterministic CIP behavior - which is the right trade-off for sensors that sleep 99.9% of the duty cycle and must wake, sample, transmit, and return to sleep within 5 ms.
Recommended
Industrial Sensor Transmitters (4-20 mA / Modbus)
The PIC18LF27K40-E/SP is well matched to industrial 4-20 mA loop-powered and Modbus RTU transmitters because of its -40 C to +125 C extended temperature grade and 1.8-3.6 V operation that draws power directly from the loop. The 10-bit ADC2 with hardware averaging and oversampling delivers stable readings from RTD, thermocouple, or bridge sensors, while the 5-bit DAC plus PWM provides excitation for sensors needing a current source. The WWDT and CRC/SCAN peripherals satisfy functional-safety requirements by detecting firmware runaway and memory corruption in unattended field nodes. With 128 KB Flash, the MCU can host Modbus, HART, or IO-Link device stacks without external memory. Compared with 32-bit Cortex-M0 alternatives, the K40 wins on analog integration (one-chip transmitter) and on-board CIPs that run timing-critical loops without CPU load.
Recommended
HVAC and Thermostat Controls
The PIC18LF27K40-E/SP is a strong fit for HVAC thermostats and zone controllers thanks to its 24-channel ADC (multiple NTC10K inputs), three PWM channels with Complementary Waveform Generator (CWG) for triac-fired loads, and ZCD for zero-cross switching that minimizes EMI on relay contacts. The -40 C to +125 C operating range covers attic and outdoor equipment enclosures. CWG and CCP peripherals generate dead-band-controlled half-bridge signals for triacs driving 24 VAC loads, while the 5-bit DAC plus op-amp output stages support 0-10 V proportional valves. With 128 KB Flash, the MCU can host user-interface graphics libraries, BLE stacks for app pairing, and OTA firmware updates. Compared with PIC16F parts at the same price, the K40 adds ZCD, CWG, and PPS that replace a half-dozen discrete components.
Recommended
Automotive Body and Lighting Nodes
The PIC18LF27K40-E/SP's -40 C to +125 C extended temperature grade suits automotive body controllers, lighting modules, and LIN sub-nodes. The 'F' core variant (PIC18F27K40-E/SP) is preferred for direct 12 V battery operation after regulation; the LF variant in this design typically runs from a 3.3 V post-regulator rail. CWG produces complementary PWM signals for half-bridge LED drivers and motor H-bridges, ZCD enables AC zero-cross detection for 115 V lamp dimming via triac, and ADC2 reads battery voltage and current sense for load-dump diagnostics. Compared with dedicated ASSPs, the K40's programmable CIPs allow one MCU to replace multiple timer ICs and analog comparators in seat controllers or mirror modules. AEC-Q100 qualification is typically cited for the automotive-grade 'F' variant, not the LF part.
Recommended
Smart Metering (Water / Heat / Gas)
The PIC18LF27K40-E/SP is engineered for battery-powered smart water, heat, and gas meters because its XLP core draws under 1 uA average current while keeping RTCC and tamper-detection interrupts alive. The 24-channel 10-bit ADC2 supports pulse counting from reed switches, Hall sensors, or optical encoders used in flow meters. The 128 KB Flash accommodates wireless-M-Bus, LoRaWAN, or Sigfox protocol stacks with margin for secure bootloaders and tamper logging. ZCD detects meter tampering by sensing AC mains when battery is removed. Compared with PIC16F1xxx parts, the K40 offers double the Flash and Core Independent Peripherals that allow the meter to operate for 10+ years on a single lithium battery.
Recommended
White Goods and Consumer Appliance Control
The PIC18LF27K40-E/SP serves as the main controller in washing machines, dishwashers, ovens, and refrigerators because its rich peripheral set (CWG, CCP/PWM, ADC2, DAC, comparators, ZCD) replaces multiple discrete ICs while the 128 KB Flash hosts motor-control libraries and user-interface code. The -40 C to +125 C temperature range covers under-cabinet and outdoor-rated appliances. Complementary PWM via CWG drives BLDC and PMSM motors for compressors and pumps without an external gate driver for low-current stages; ADC2 with computation reads motor current and temperature for sensorless control loops. UART/SPI/I2C with PPS connects capacitive touch, LED displays, and BLE modules for app control. Compared with older PIC18F46K22 designs, the K40 adds ZCD, CWG, and ADC2 computation that simplify inverter-style motor drives.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF27K40-E/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F27K40-E/SP | PIC18LF27K40-I/SP | PIC18LF26K40-E/SP | PIC18LF25K40-E/SP |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SPDIP (SP) | 28-pin SPDIP (SP) - same | 28-pin SPDIP (SP) - same | 28-pin SPDIP (SP) - same | 28-pin SPDIP (SP) - same |
| Core | PIC18 8-bit LF (1.8-3.6V) | PIC18 8-bit F (2.3-5.5V) | PIC18 8-bit LF (1.8-3.6V) - same | PIC18 8-bit LF (1.8-3.6V) - same | PIC18 8-bit LF (1.8-3.6V) - same |
| Max CPU Frequency | 64 MHz (16 MIPS) | 64 MHz - same | 64 MHz - same | 64 MHz - same | 64 MHz - same |
| Flash | 128 KB | 128 KB - same | 128 KB - same | 64 KB (-50%) | 32 KB (-75%) |
| RAM | 4 KB | 4 KB - same | 4 KB - same | 3.6 KB (-10%) | 2 KB (-50%) |
| EEPROM | 256 B | 256 B - same | 256 B - same | 256 B - same | 256 B - same |
| Operating Temperature | -40 C to +125 C (E) | -40 C to +125 C (E) - same | -40 C to +85 C (I) - narrower | -40 C to +125 C (E) - same | -40 C to +125 C (E) - same |
| Core Independent Peripherals | CWG, CCP, PWM, ADC2, DAC, ZCD, WWDT, CRC/SCAN, CLC | Same CIP set - identical | Same CIP set - identical | Same CIP set - identical | Same CIP set - identical |
Key Differentiators
- Highest-density Flash in 28-pin SPDIP K40 family (vs PIC18LF26K40-E/SP)
- Extended temperature grade for industrial deployments (vs PIC18LF27K40-I/SP)
- Lowest VDD minimum for single-cell Li-ion direct connection (vs PIC18F27K40-E/SP)
Design Notes
Use a 100 nF ceramic decoupling capacitor on each VDD/VSS pair (pin 8/11 and pin 12) placed within 3 mm of the package pins, plus a 10 uF bulk capacitor on the main VDD rail. The XLP core draws < 50 nA in deep sleep with RTCC running; verify Iq under load before sizing the bulk capacitor. When using the on-chip 32 kHz SOSC for RTCC, connect a 32.768 kHz crystal between RA6 (SOSCO) and RA7 (SOSCI) with 12 pF load capacitors. Avoid routing the crystal traces over switching signals - the RTCC accuracy directly affects calendar functions in metering applications.
The PIC18LF27K40-E/SP in the 28-pin SPDIP package has a theta_JA of approximately 50-60 C/W (estimate based on the SPDIP family typical; verify against the Microchip PIC18 (L)F27/47K40 datasheet thermal section). At 64 MHz and 3.3 V the dynamic current is ~14 mA, so power dissipation is roughly 46 mW. In an enclosed industrial enclosure at +85 C ambient, junction rise is ~3 C, well within the +125 C limit. For hot-spot applications like motor drive, route the ground paddle to a 0.5 square-inch copper pour to spread heat, and ensure the SPI clock trace to the gate driver does not exceed 10 MHz.
Route ICSP signals (RB6/ICSPCLK and RB7/ICSPDAT) to a 5-pin header accessible from the board edge for in-circuit programming and debug. The PPS remap function lets you move UART, SPI, I2C, PWM, and CLC outputs to most I/O pins, but only one peripheral function per pin at a time - verify the schematic pin-assignment matches the MPLAB Code Configurator (MCC) pin-manager settings before committing layout. Keep ADC analog traces (RA0-RA5, RC0-RC3) short and away from PWM switching traces to minimize digital noise coupling into measurements; add a ground guard ring around sensitive analog inputs.
Do not exceed 3.6 V on VDD - the LF core is not 5 V tolerant, unlike the F variant. When migrating firmware from PIC18F27K40 to PIC18LF27K40, recompile under XC8 with the LF device selected; some CIP registers differ between LF and F variants. The CONFIG words must be set before code execution - leaving them at default values disables the PLL and may run the part at 1 MHz internal oscillator, which looks like a 'dead' MCU on first power-up. Use MCC-generated configuration defaults to avoid this pitfall. Watchdog timer must be either enabled or explicitly cleared in software; default-disabled WWDT may mask runaway code in field deployments.
Compliance Information
RoHS and lead-free per Microchip product page. The PIC18LF27K40-E/SP is the standard (non-automotive) grade; for AEC-Q100 qualified automotive use, consider the PIC18F27K40-E/SP variant or consult Microchip's automotive-grade portfolio.
