PIC18LF24K42-I/SO - 64MHz 8-bit MCU, 16KB Flash, 28-SOIC
MPN: PIC18LF24K42-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $1.95 | $1.95 |
| 10 | $1.74 | $17.40 |
| 100 | $1.45 | $145.00 |
| 500 | $1.18 | $590.00 |
| 1,000 | $0.96 | $960.00 |
PIC18LF24K42-I/SO Overview
A microcontroller (MCU) is a single-chip computer that contains a CPU, memory (Flash/RAM/EEPROM), and programmable peripherals on one die. The PIC18 family is an 8-bit Harvard-architecture RISC MCU family from Microchip; within the broader taxonomy, PIC18 sits under 8-bit microcontrollers -> microcontrollers -> microcontrollers (MCUs) -> integrated circuits. The LF prefix indicates the low-voltage/F-version that operates from 1.8 V to 3.6 V, suiting battery-powered designs.
Key features include 25 I/O lines, 10-bit/12-bit ADC with Computation (ADC2), a 5-bit DAC, two comparators, two DMA channels, vector interrupts, and PWM outputs. The device supports eXtreme Low Power (XLP) modes with multiple idle/sleep states and peripheral operation while the CPU is halted, making it well suited for energy-harvesting and always-on sensor nodes. Core-independent peripherals (CIPs) such as the ADC2, DMA, timers, and PWM can inter-operate without CPU intervention, reducing wake events and average current.
The PIC18LF24K42 uses Microchip's enhanced mid-range core with a hardware multiplier and a modified Harvard architecture that allows linear access to 16 KB of Flash. The integrated 12-bit ADC2 supports averaging, oversampling, threshold comparison, and automated acquisition to offload the CPU. A peripheral pin select (PPS) subsystem routes digital peripherals to a wide choice of I/O pins, simplifying PCB routing in mixed-signal designs.
Typical applications include IoT sensor nodes, low-power wireless-connected devices (BLE/LoRa endpoints), home appliances, industrial sensor transmitters, battery-powered instrumentation, and consumer electronics where sleep current and peripheral autonomy are critical. The 28-SOIC footprint simplifies hand-soldering and rework during prototyping.
When designing with this part, use Microchip's MPLAB X IDE and XC8 compiler. Decouple VDD with a 100 nF ceramic capacitor close to each supply pin, and route the ICSP lines (PGx/PDx) to an in-circuit programming header for field updates. The LF variant is required if the supply rail falls below 2.0 V at any time.
This page synthesizes distributor pricing, drop-in same-package alternatives from Microchip's PIC18(L)FxxK42 family, and practical low-power design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18LF24K42-I/SO — 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 PIC18LF24K42-I/SO (same form factor and footprint) — differing in Package, ADC, Comparators, Core Architecture, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F24K42-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF25K42-I/SO
✅ Drop-In✓ In Stock
$1.62 / Unit
View Datasheet →PIC18LF26K42-I/SO
✅ Drop-In✓ In Stock
$1.92 / Unit
View Datasheet →PIC18LF24K40-I/SO
✅ Drop-In✓ In Stock
$0.99 / Unit
View Datasheet →PIC18LF24K42-E/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF46K42-I/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF24K42-I/SO Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Maximum Clock Frequency | 64 MHz |
| Program Memory (Flash) | 16 KB (8K x 16) |
| Data RAM | 1 KB |
| Data EEPROM | 256 B |
| Number of I/O Lines | 25 |
| ADC | 12-bit ADC2 with computation, up to 24 channels |
| DAC | 5-bit DAC |
| Comparators | 2 |
| DMA Channels | 2 |
| Timers | 10 |
| PWM Channels | Yes (multiple) |
| Operating Supply Voltage (LF) | 1.8 V to 3.6 V |
| Operating Temperature | -40 C to +85 C (Industrial -I) |
| Package | 28-pin SOIC (SO) |
| Mounting Type | Surface Mount |
| Low-Power Technology | XLP (eXtreme Low Power) |
| Vector Interrupts | Yes |
| RoHS Status | Compliant |
PIC18LF24K42-I/SO Pin Configuration
| Pin 1 | RA2 — Port A bit 2 / analog input |
| Pin 2 | RA3 — Port A bit 3 |
| Pin 3 | RA4 — Port A bit 4 |
| Pin 4 | RA5 — Port A bit 5 |
| Pin 5 | RA6 — Port A bit 6 |
| Pin 6 | RA7 — Port A bit 7 |
| Pin 7 | VSS — Ground reference |
| Pin 8 | RA0 — Port A bit 0 |
| Pin 9 | RA1 — Port A bit 1 |
| Pin 10 | OSC1 — External oscillator input |
| Pin 11 | OSC2 — External oscillator output |
| Pin 12 | RC0 — Port C bit 0 |
| Pin 13 | RC1 — Port C bit 1 |
| Pin 14 | RC2 — Port C bit 2 |
| Pin 15 | RC3 — Port C bit 3 |
| Pin 16 | RC4 — Port C bit 4 |
| Pin 17 | RC5 — Port C bit 5 |
| Pin 18 | RC6 — Port C bit 6 |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0 — Port B bit 0 |
| Pin 22 | RB1 — Port B bit 1 |
| Pin 23 | RB2 — Port B bit 2 |
| Pin 24 | RB3 — Port B bit 3 |
| Pin 25 | RB4 — Port B bit 4 |
| Pin 26 | RB5 — Port B bit 5 |
| Pin 27 | RB6 — Port B bit 6 / ICSPCLK |
| Pin 28 | RB7 — Port B bit 7 / ICSPDAT |
Typical Applications
PIC18LF24K42-I/SO is suitable for 6 applications: Battery-Powered IoT Sensor Node, Home Appliance Control Board, Industrial Sensor Transmitter (4-20 mA / IO-Link), Wearable Health / Fitness Device, Automotive Body & Lighting Module (sub-system MCU), Smart Energy Meter / Sub-Meter.
Battery-Powered IoT Sensor Node
The PIC18LF24K42-I/SO is purpose-built for coin-cell or 2xAA battery IoT sensor nodes. Its 1.8 V to 3.6 V LF supply range supports direct connection to single-cell Li-ion chemistries, and XLP sleep currents typically below 1 uA extend operating life to multi-year horizons. The ADC2 (computation) plus DMA channels let a temperature or humidity sensor stream into memory while the CPU remains in sleep, waking only on a comparator threshold or RTC event. The 16 KB Flash is ample for BLE/LoRa stack fragments plus sensor-fusion glue code.
Recommended
Home Appliance Control Board
In washing machines, dishwashers, and induction cooktops, the PIC18LF24K42-I/SO drives the user-interface MCU role, scanning capacitive touch keys, triac-fired heater loads, and 7-segment LED displays. Its 25 I/O lines, hardware PWM, and 12-bit ADC2 handle simultaneous zero-cross detection, motor speed sensing, and temperature monitoring. The K42 family datasheet example code accelerates time-to-market for IEC 60730 Class B software self-test routines required in many white goods. The wide 1.8 V to 3.6 V range tolerates unregulated 3.3 V rails from simple transformer supplies.
Recommended
Industrial Sensor Transmitter (4-20 mA / IO-Link)
For 4-20 mA loop-powered or 3-wire industrial transmitters, the PIC18LF24K42-I/SO digitizes a bridge sensor with its 12-bit ADC2, performs linearization and temperature compensation, then drives an IO-Link PHY or a current-loop DAC. The two comparators enable window comparators for sensor-health diagnostics without CPU wakeup. The 64 MHz core performs floating-point compensation in single-digit milliseconds per sample. The industrial -40 C to +85 C temperature range and on-chip EEPROM for calibration storage meet typical process-control environments.
Recommended
Wearable Health / Fitness Device
Wearables such as heart-rate straps, smartwatches, and step counters rely on the PIC18LF24K42-I/SO for sensor aggregation at very low average current. The PIC18 core at 64 MHz processes PPG and motion sensor streams from an I2C/SPI bus while DMA offloads byte shuffling. XLP sleep with RTC keep-alive drops average current into the low-uA range, critical for coin-cell runtime. The compact 28-SOIC footprint is unusual for wearables, but the part is widely used in companion/debug boards, charging cradles, and BLE dongles that pair with the wearable.
Recommended
Automotive Body & Lighting Module (sub-system MCU)
Within body-control modules, interior LED drivers, and ambient lighting controllers, the PIC18LF24K42-I/SO drives WS2812-style LED strips and LIN-bus sub-modules. The 12-bit ADC2 reads battery voltage and ambient light sensors, while PWM channels fade RGB channels smoothly. The wide supply range and 25 I/O lines fit comfortably inside a 32-channel LED module. For full automotive AEC-Q100 needs, designers move up to the AEC-qualified PIC18F46K42 family variants. The 28-SOIC package is hand-solder friendly for prototype lead times.
Recommended
Smart Energy Meter / Sub-Meter
Single-phase residential energy meters and current-sensing sub-meters use the PIC18LF24K42-I/SO to sample current and voltage via 12-bit ADC2, compute RMS power, and drive an LCD or UART-modulated display. The 16 KB Flash fits the IEC 62053-21/22 calibration math, and 256 B EEPROM holds calibration tables. The K42 DMA channels stream ADC samples into RAM without CPU intervention, freeing cycles for metrology math. The industrial -40 C to +85 C temperature range is sufficient for indoor meter enclosures, while the LF supply is appropriate for 3.3 V-powered sub-meters.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF24K42-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F24K42-I/SO | PIC18LF25K42-I/SO | PIC18LF26K42-I/SO | PIC18LF24K40-I/SO |
|---|---|---|---|---|---|
| Package | 28-SOIC (SO) | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same | 28-SOIC (SO) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 16 KB | 16 KB | 32 KB | 64 KB | 8 KB |
| RAM | 1 KB | 1 KB | 2 KB | 4 KB | 1 KB |
| Supply Voltage | 1.8 V to 3.6 V | 2.0 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 |
| Max Clock Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| I/O Lines | 25 | 25 | 25 | 25 | 25 |
| ADC | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 12-bit ADC2 | 10-bit ADC |
| Temperature Grade | -40 C to +85 C (I) | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C | -40 C to +85 C |
| EEPROM | 256 B | 256 B | 256 B | 1024 B | 256 B |
Key Differentiators
- Wider low-voltage operating range with full peripheral set (vs PIC18F24K42-I/SO)
- Doubles Flash and RAM over the K40 base for richer firmware (vs PIC18LF24K40-I/SO)
- Core-independent peripherals eliminate CPU wake-ups (vs PIC18LF24K40-I/SO)
Design Notes
Estimated: Decouple each VDD/VSS pair with a 100 nF X7R ceramic capacitor placed within 5 mm of the IC pins. For battery designs running below 2.5 V, add a bulk 1 uF to 4.7 uF tantalum or polymer cap near VDD to ride out transmit bursts from a radio. Place a 10 kohm pull-up on MCLR to keep the part out of reset during brownout events. The K42 family datasheet recommends a low-ESR cap to achieve the deep-sleep current figures in Section 30 (Electrical Characteristics).
Estimated: Route the ICSP lines (RB6/ICSPCLK, RB7/ICSPDAT) to a 6-pin header with no series resistors; place the header on the same PCB edge as the SOIC for easy debugger access. Group analog and digital ground returns separately and tie them together at a single point near the VDD bypass caps. Keep the crystal traces short (under 5 mm each) and surrounded by a ground guard ring to avoid EMI pickup on OSC1/OSC2.
Do not operate the LF variant above 3.6 V - this is the most common parametric failure mode observed on Microchip K42 returns. For designs where the rail could exceed 3.6 V, choose the PIC18F24K42-I/SO (2.0 V to 5.5 V) instead. Ensure the AVDD pin is tied to VDD even if the ADC is unused, otherwise the part may enter an indeterminate state on POR. When migrating from K40 to K42 firmware, verify register layouts for ADC2 and the DMA engine since they differ substantially.
Compliance Information
RoHS and lead-free status per Microchip product page. AEC-Q100 not qualified - the LF part is industrial grade -40 C to +85 C. Halogen-free status not explicitly listed in the verified web data.
