PIC18LF27K40-I/SP - 128KB Flash 8-bit MCU, 28-SPDIP | Microchip
MPN: PIC18LF27K40-I/SP ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.18 | $3.18 |
| 10 | $2.94 | $29.40 |
| 100 | $2.55 | $255.00 |
| 500 | $2.21 | $1,105.00 |
| 1,000 | $1.95 | $1,950.00 |
PIC18LF27K40-I/SP Overview
A PIC18 microcontroller is an 8-bit Harvard-architecture MCU built around an enhanced RISC core with hardware multiply, designed for embedded control applications that need deterministic interrupt latency and abundant I/O. PIC18F devices sit in the broader PIC family hierarchy: PIC10/12/16/18 -> 8-bit MCU -> microcontroller -> embedded IC -> semiconductor. The 'LF' prefix indicates the low-voltage (1.8–3.6 V) variant with eXtreme Low Power (XLP) technology, which delivers nanoWatt sleep currents, while the 'F' prefix operates at 2.3–5.5 V. Both are functionally compatible on the same package footprint.
Key features of the PIC18LF27K40 include 25 digital I/O pins, four 16-bit timers, two comparators with selectable references, a 10-bit ADC with computation (ADC2) oversampling, a 5-bit DAC, Zero-Cross Detection (ZCD), and configurable Complementary Waveform Generator (CWG) for power-driver control. The Peripheral Pin Select (PPS) allows flexible remapping of digital peripherals to any I/O, easing PCB layout.
Architecturally, the device integrates a 16-level hardware stack, self-programming Flash with read-while-write, and idle/doze/peripheral module disable (PMD) modes for power tuning. The XLP technology enables deep sleep currents in the nanoampere range, supporting coin-cell applications.
Typical applications include industrial sensor nodes, low-power IoT end-points, consumer appliance control, battery-powered instrumentation, motor control signal conditioning, and automotive body/comfort subsystems. Designers benefit from the peripheral integration that minimizes external components.
When laying out, ensure the VDD/VSS pair has 0.1 µF decoupling placed within 5 mm of each pin and respect the ICSP™/ICD pinout for in-circuit programming. The wide 1.8–3.6 V supply enables direct Li-Ion or 2× AA operation without a separate regulator.
This page synthesizes distributor pricing, drop-in same-package alternatives, and practical design notes not found on a single distributor page or the bare datasheet summary.
Drop-in alternatives for PIC18LF27K40-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 PIC18LF27K40-I/SP (same form factor and footprint) — differing in ADC, Package, Program Memory (Flash), MSL Level, Comparators.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F27K40-I/SP
✅ Drop-In✓ In Stock
$2.45 / Unit
View Datasheet →PIC18LF25K40-I/SP
✅ Drop-In✓ In Stock
$1.74 / Unit
View Datasheet →PIC18LF25K40-I/SO
✅ Drop-In✓ In Stock
$1.65 / Unit
View Datasheet →PIC18LF26K40-I/SS
✅ Drop-In✓ In Stock
$1.18 / Unit
View Datasheet →PIC18LF27K40-I/SP Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC |
| Program Memory (Flash) | 128 KB (64K x 16) |
| Data SRAM | 4 KB (3,536 bytes per pcbelectronics listing) |
| EEPROM | 256 B |
| Maximum CPU Frequency | 64 MHz |
| Operating Voltage Range | 1.8 V to 3.6 V |
| Number of I/O Pins | 25 |
| ADC | 10-bit ADC2 with computation |
| DAC | 5-bit DAC |
| Comparators | 2 with selectable reference |
| Timers | 4 x 16-bit / 2 x 8-bit |
| Communication | EUSART, SPI, I2C (via PPS) |
| PWM / CCP / CWG | PWM, CCP, Complementary Waveform Generator |
| Core Independent Peripherals | CWG, WWDT, CRC/SCAN, ZCD, PPS, PMD |
| Operating Temperature | -40C to +85C (Industrial, 'I') |
| Package | 28-pin SPDIP (through-hole) |
| Mounting Type | Through Hole |
| MSL Level | 1 (not moisture-sensitive) |
| RoHS Status | Compliant |
| Programming | ICSP / ICD (in-circuit) |
PIC18LF27K40-I/SP Pin Configuration
| Pin 1 | MCLR/RE3 — Master Clear (Reset) input or digital input RE3 |
| Pin 2 | RA0 — Analog input AN0 / digital I/O |
| Pin 3 | RA1 — Analog input AN1 / digital I/O |
| Pin 4 | RA2 — Analog input AN2 / digital I/O |
| Pin 5 | RA3 — Analog input AN3 / digital I/O |
| Pin 6 | RA4 — Analog input AN4 / digital I/O |
| Pin 7 | RA5 — Analog input AN5 / digital I/O |
| Pin 8 | RA6 — Oscillator output / digital I/O |
| Pin 9 | RA7 — Oscillator input / digital I/O |
| Pin 10 | VSS — Ground reference |
| Pin 11 | VDD — Positive supply (1.8-3.6V) |
| Pin 12 | RB0 — Digital I/O / interrupt-on-change |
| Pin 13 | RB1 — Digital I/O / interrupt-on-change |
| Pin 14 | RB2 — Digital I/O / interrupt-on-change |
| Pin 15 | RB3 — Digital I/O / interrupt-on-change |
| Pin 16 | RB4 — Digital I/O / interrupt-on-change |
| Pin 17 | RB5 — Digital I/O / interrupt-on-change |
| Pin 18 | RB6 — ICSPCLK / digital I/O |
| Pin 19 | RB7 — ICSPDAT / digital I/O |
| Pin 20 | VSS — Ground reference |
| Pin 21 | VDD — Positive supply (1.8-3.6V) |
| Pin 22 | RC0 — Digital I/O |
| Pin 23 | RC1 — Digital I/O |
| Pin 24 | RC2 — Digital I/O |
| Pin 25 | RC3 — Digital I/O / SCL |
| Pin 26 | RC4 — Digital I/O / SDA |
| Pin 27 | RC5 — Digital I/O |
| Pin 28 | RC6 — Digital I/O / TX |
| Pin 29 | RC7 — Digital I/O / RX |
Typical Applications
PIC18LF27K40-I/SP is suitable for 6 applications: Low-Power IoT Sensor Node, Industrial Automation Control, Consumer Appliance Control Board, Battery-Powered Instrumentation, Automotive Body & Comfort Subsystem, Lighting & Display Driver.
Low-Power IoT Sensor Node
The PIC18LF27K40-I/SP's 128 KB Flash and XLP nanoWatt technology enable multi-protocol sensor nodes running Microchip's MiWi or custom Zigbee stacks on a coin-cell or 2xAA supply. The device's deep-sleep current under 50 nA with RTCC active, plus 4 KB RAM for buffering sensor reads, makes it ideal for years-long battery life in environmental monitoring. The 10-bit ADC2 with oversampling handles temperature, humidity, and analog front-end signals, while EUSART/SPI/I2C connects to radio modules. Designers benefit from PPS remapping that lets the radio share I/O with sensor interfaces without board rework.
Recommended
Industrial Automation Control
The PIC18LF27K40-I/SP's Core Independent Peripherals - including the Complementary Waveform Generator (CWG), Zero-Cross Detect (ZCD), and PWM/CCP - are well-suited to industrial control of small motor drivers, SSR triggers, and 4-20 mA loops. The device operates reliably from -40C to +85C (Industrial, 'I' suffix) and supports 1.8-3.6 V supply tolerant of 24 V industrial rails after regulation. Hardware CRC/SCAN validates Flash integrity in the field, while WWDT provides a fail-safe against firmware lockup. The 25 I/O pins drive multiple sensors and discrete actuators simultaneously.
Recommended
Consumer Appliance Control Board
The PIC18LF27K40-I/SP's compact 128 KB Flash footprint fits appliance firmware for washers, dishwashers, and small kitchen devices where display, motor, and sensor I/O must coexist. The 5-bit DAC and dual comparators handle direct thermistor interfaces, while PWM drives TRIAC/SSR-based heater control. CWG generates complementary drive signals for half-bridge motor drivers without CPU overhead, freeing the core for user-interface and safety logic. The wide 1.8-3.6 V supply also enables direct Li-Ion backup on smart appliances.
Recommended
Battery-Powered Instrumentation
The PIC18LF27K40-I/SP's XLP eXtreme Low Power technology enables handheld multimeters, portable data loggers, and field calibration instruments that operate for hundreds of hours on 2xAA cells. The 10-bit ADC2 with computation (oversampling) achieves effective 12-bit resolution for precision sensor reads, while idle/doze/PMD modes cut peripheral power during measurement gaps. The 64 MHz CPU bandwidth processes FFT or statistical analysis on captured data before returning to sleep. RTCC with internal 32 kHz oscillator maintains a wall-clock across deep sleep without external crystal.
Recommended
Automotive Body & Comfort Subsystem
While the 'I' (Industrial) grade suits non-safety body controllers, the PIC18LF27K40-I/SP's wide 1.8-3.6 V supply and rich peripheral set fit door modules, seat controllers, mirror adjusters, and interior lighting nodes. LIN bus via EUSART handles body-domain communication, and PWM/CWG drive LED matrix dimming and small DC motors. For under-hood or safety-critical applications, the AEC-Q100 qualified PIC18F27K40-E/SP or PIC18LF26K42-E/SP provides automotive-grade reliability. CRC/SCAN and WWDT support ISO 26262 diagnostic requirements at lower ASIL levels.
Recommended
Lighting & Display Driver
The PIC18LF27K40-I/SP's CWG, multiple PWM channels, and ZCD (zero-cross detect) integrate AC-dimmable LED drivers and small TFT or segment LCD controls. ZCD triggers PWM at AC line zero-cross for TRIAC-dimmable luminaires without external zero-cross circuitry, while the CWG generates dead-time-controlled complementary drive for high-brightness LED strings. Peripheral Pin Select (PPS) routes SPI to multiple display interfaces without remapping PCB traces. The 128 KB Flash accommodates DALI or DMX protocol stacks with custom lighting profiles.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF27K40-I/SP — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F27K40-I/SP | PIC18LF25K40-I/SP | PIC18LF25K40-I/SO | PIC18LF26K40-I/SS |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SPDIP | 28-SPDIP (drop-in) | 28-SPDIP (drop-in) | 28-SOIC (drop-in for SOIC layouts) | 28-SSOP (drop-in for SSOP layouts) |
| Flash Memory | 128 KB | 128 KB | 32 KB | 32 KB | 64 KB |
| RAM | 4 KB | 4 KB | 2 KB | 2 KB | 2 KB |
| Operating Voltage | 1.8 V to 3.6 V | 2.3 V to 5.5 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 1.8 V to 3.6 V |
| Maximum Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| I/O Pins | 25 | 25 | 25 | 25 | 25 |
| ADC / DAC | 10-bit ADC2 / 5-bit DAC | 10-bit ADC2 / 5-bit DAC | 10-bit ADC / 5-bit DAC | 10-bit ADC / 5-bit DAC | 10-bit ADC / 5-bit DAC |
| Core Independent Peripherals | CWG, WWDT, CRC/SCAN, ZCD, PPS | CWG, WWDT, CRC/SCAN, ZCD, PPS | CWG, WWDT, ZCD, PPS (no CRC/SCAN) | CWG, WWDT, ZCD, PPS (no CRC/SCAN) | CWG, WWDT, ZCD, PPS (no CRC/SCAN) |
| Unit Price (1 pc, USD) | 3.18 | 3.05 | 2.85 | 2.85 | 2.95 |
Key Differentiators
- Highest Flash density in 28-SPDIP XLP family (vs PIC18LF25K40-I/SP)
- Richest Core Independent Peripheral set in 28-pin class (vs PIC18LF26K42-I/SP)
- Lowest voltage operation in 28-SPDIP XLP family (vs PIC18F27K40-I/SP)
Design Notes
Place a 0.1 µF decoupling capacitor within 5 mm of each VDD/VSS pair (pins 11/10 and 21/20). Add a bulk 10 µF tantalum or ceramic on the main VDD rail. For battery applications, route the MCLR pull-up (typically 10 kΩ) directly to VDD rather than through long traces, to ensure clean power-on reset transitions. The XLP deep-sleep current drops to sub-50 nA when peripherals are disabled via PMD and the ADC is off.
Reserve the ICSP/ICD footprint (RB6/RB7) on the PCB even if programming is via bootloader, to allow field firmware updates and debugging. Keep the ICSP traces short and away from switching nodes. Place the 28-SPDIP socket or through-holes on a 0.1-inch (2.54 mm) grid with sufficient clearance around the MCLR pin for a test clip. PPS routing allows digital peripherals to be remapped at compile time, so reserve flexibility on PCB trace assignment.
Do not exceed 3.6 V on VDD - the LF variant is not 5 V tolerant. For 5 V systems, use the PIC18F27K40-I/SP variant. Ensure config bits select the correct oscillator mode (e.g., HS for >4 MHz crystal, INTOSC for internal 64 MHz). The comparator and ADC reference voltages must be configured before use; the FVR (Fixed Voltage Reference) module can source 1.024 V, 2.048 V, or 4.096 V for stable ADC measurements.
At 64 MHz full-bandwidth operation with all peripherals active, the PIC18LF27K40-I/SP draws ~10 mA typical and ~15 mA worst case (per DS40001891). The 28-SPDIP package provides a thermal resistance (theta_JA) of approximately 80 C/W, so a 5 V -> 3.3 V LDO plus the MCU at full load dissipates ~50 mW - no heatsink needed. Estimated: at 25°C ambient, junction rise is approximately 4°C; well within the -40C to +85C industrial rating.
Compliance Information
RoHS/REACH compliant per Microchip product page. Not AEC-Q100 qualified - for automotive applications, use the PIC18F27K40-E/SP (AEC-Q100) or PIC18LF27K40-E/SP variant instead.
