PIC18LF46K42-I/PT - 8-Bit 64MHz MCU, 64KB Flash | Microchip
MPN: PIC18LF46K42-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.1 | $4.10 |
| 10 | $3.65 | $36.50 |
| 100 | $3.05 | $305.00 |
| 500 | $2.68 | $1,340.00 |
| 1,000 | $2.4 | $2,400.00 |
PIC18LF46K42-I/PT Overview
An 8-bit MCU (microcontroller unit) is a single-chip computer that integrates a CPU, non-volatile program memory (Flash), volatile data memory (RAM), EEPROM, and a rich set of peripherals (ADC, timers, communication interfaces). PIC18 microcontrollers use a RISC-based Harvard architecture and are widely deployed in embedded control, sensor conditioning, and human-machine-interface designs. The PIC18LF46K42-I/PT specifically belongs to the "LF" low-voltage sub-family of the K42 family, optimized for battery-powered and energy-harvesting applications thanks to its eXtreme Low Power (XLP) features.
Key features include 64 KB self-programmable Flash, 4 KB SRAM, 1 KB EEPROM, a 12-bit ADC with up to 35 channels, a 5-bit DAC, two op-amps, two comparators, DMA, vector interrupts, Core Independent Peripherals (CIP), and multiple communication interfaces: I2C, SPI, UART with LIN support. The device runs at up to 64 MHz instruction-clock frequency, executes 16-bit instructions in one cycle (16 MIPS peak), and supports 1.8 V to 3.6 V operation across an industrial -40C to +85C temperature range.
The architecture integrates a high-performance 8-bit RISC core with a 31-level hardware stack, hardware multiply/divide, and direct memory access (DMA) for autonomous data movement between peripherals and RAM. The 12-bit ADC2 (up to 35 channels) and 5-bit DAC enable mixed-signal designs without external components, while two on-chip op-amps and comparators form complete analog front-ends for sensor signal conditioning.
Typical applications include IoT sensor nodes, low-power wireless devices, battery-powered instrumentation, industrial control modules, automotive body electronics, and consumer appliances. The LF voltage range (1.8 V-3.6 V) and XLP features (nanoWatt XLP, IDLE/DOZE modes) make it especially suitable for energy-constrained designs.
When designing with this MCU, ensure decoupling follows Microchip's recommended 100 nF + bulk capacitor arrangement near VDD/AVDD pins. Program the configuration bits to match the application oscillator and watchdog requirements, and reserve the unused I/O pins with the UNUSED pin macro to minimize current leakage in deep sleep.
This page synthesizes distributor pricing, drop-in TQFP-44 alternatives within the PIC18 K42 family, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18LF46K42-I/PT — 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 PIC18LF46K42-I/PT (same form factor and footprint) — differing in Package, ADC, Communication, Core Architecture, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF46K42-E/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F46K42-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF46K40-I/PT
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →PIC18LF46K22-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF46K42-I/PT Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Family | PIC18FxxK42 |
| Program Memory (Flash) | 64 KB (32K x 16) |
| RAM | 4 KB |
| EEPROM | 1 KB |
| Maximum CPU Frequency | 64 MHz |
| Operating Voltage | 1.8 V to 3.6 V |
| ADC | 12-bit, up to 35 channels (ADC2) |
| DAC | 5-bit, 1 channel |
| Comparators | 2 |
| Op-Amps | 2 (on-chip) |
| DMA | Yes |
| Communication Interfaces | I2C, SPI, UART (with LIN) |
| Number of I/O Pins | 36 |
| Timers/PWM | Multiple 8/16-bit timers, PWM, CCP |
| Package | 44-pin TQFP (PT) 10x10 mm |
| Mounting Type | Surface Mount |
| Operating Temperature | -40C to +85C (Industrial) |
| Data Bus Width | 8-bit |
| Low-Power Features | XLP (nanoWatt), IDLE/DOZE/Sleep modes |
| RoHS Status | Compliant |
PIC18LF46K42-I/PT Pin Configuration
| Pin 1 | RB7 — PORTB I/O bit 7 (ICSP programming data) |
| Pin 2 | RB6 — PORTB I/O bit 6 (ICSP programming clock) |
| Pin 3 | RA5 — PORTA I/O bit 5 |
| Pin 4 | RA4 — PORTA I/O bit 4 |
| Pin 5 | RA3 — PORTA I/O bit 3 |
| Pin 6 | RA2 — PORTA I/O bit 2 |
| Pin 7 | RA1 — PORTA I/O bit 1 |
| Pin 8 | RA0 — PORTA I/O bit 0 |
| Pin 9 | VSS — Ground reference |
| Pin 10 | RA7 — PORTA I/O bit 7 |
| Pin 11 | RA6 — PORTA I/O bit 6 |
| Pin 12 | RC0 — PORTC I/O bit 0 |
| Pin 13 | RC1 — PORTC I/O bit 1 |
| Pin 14 | RC2 — PORTC I/O bit 2 |
| Pin 15 | RC3 — PORTC I/O bit 3 |
| Pin 16 | RC4 — PORTC I/O bit 4 |
| Pin 17 | RC5 — PORTC I/O bit 5 |
| Pin 18 | RC6 — PORTC I/O bit 6 |
| Pin 19 | RC7 — PORTC I/O bit 7 |
| Pin 20 | VSS — Ground reference |
| Pin 21 | RD0 — PORTD I/O bit 0 |
| Pin 22 | RD1 — PORTD I/O bit 1 |
| Pin 23 | RD2 — PORTD I/O bit 2 |
| Pin 24 | RD3 — PORTD I/O bit 3 |
| Pin 25 | RD4 — PORTD I/O bit 4 |
| Pin 26 | RD5 — PORTD I/O bit 5 |
| Pin 27 | RD6 — PORTD I/O bit 6 |
| Pin 28 | RD7 — PORTD I/O bit 7 |
| Pin 29 | VSS — Ground reference |
| Pin 30 | VDD — Positive supply (1.8V-3.6V) |
| Pin 31 | RE0 — PORTE I/O bit 0 |
| Pin 32 | RE1 — PORTE I/O bit 1 |
| Pin 33 | RE2 — PORTE I/O bit 2 |
| Pin 34 | RE3 — PORTE I/O bit 3 |
| Pin 35 | AVSS — Analog ground |
| Pin 36 | AVDD — Analog positive supply |
| Pin 37 | RA5 — PORTA alternate |
| Pin 38 | RB0 — PORTB I/O bit 0 |
| Pin 39 | RB1 — PORTB I/O bit 1 |
| Pin 40 | RB2 — PORTB I/O bit 2 |
| Pin 41 | RB3 — PORTB I/O bit 3 |
| Pin 42 | RB4 — PORTB I/O bit 4 |
| Pin 43 | RB5 — PORTB I/O bit 5 |
| Pin 44 | VDD — Positive supply (1.8V-3.6V) |
Typical Applications
PIC18LF46K42-I/PT is suitable for 6 applications: IoT Sensor Node / Battery-Powered Telemetry, Industrial Control / PLC I/O Module, Automotive Body Electronics, Medical / Health Monitoring Devices, Consumer Appliance / White Goods Control, Smart Sensor / HVAC Building Automation.
IoT Sensor Node / Battery-Powered Telemetry
The PIC18LF46K42-I/PT's 1.8 V minimum supply and XLP nanoWatt Sleep currents below 50 nA make it ideal for IoT sensor nodes that spend most of their life in deep sleep. Its 12-bit ADC2 with 35 channels accepts multiple analog sensors (temperature, humidity, light) without external muxes, while 4 KB RAM buffers local measurements and 1 KB EEPROM stores calibration constants. The UART with LIN and I2C/SPI masters connect to wireless modules (LoRa, BLE, sub-GHz) for periodic data upload. The K42's DMA engine allows autonomous ADC-to-RAM transfers without CPU wake-up, extending battery life by 30-50% versus CPU-driven sampling.
Recommended
Industrial Control / PLC I/O Module
In industrial PLCs and remote I/O modules, the PIC18LF46K42-I/PT provides the analog and digital I/O density required for sensor aggregation and actuator control. Its 12-bit ADC with 35 channels reads multiple 4-20 mA loops or 0-10 V signals through external resistor dividers, while the on-chip op-amps and comparators implement threshold detection and signal conditioning directly on the MCU. The UART with LIN/RS-485 enables Modbus and LIN-bus communication, while I2C/SPI connect to digital isolators and gate drivers. The -40C to +85C industrial temperature range supports cabinet-mounted industrial environments without additional thermal management.
Recommended
Automotive Body Electronics
The PIC18LF46K42-I/PT's wide operating voltage (1.8 V-3.6 V with internal LDO supporting automotive 12 V battery via external regulator) and rich peripheral set fit automotive body modules such as lighting controllers, seat controllers, and HVAC panels. The LIN 2.x UART supports LIN-bus slave communication commonly used in body networks, while PWM channels drive LED dimming and motor speed control. The CIP (Core Independent Peripherals) including CLC and PWM allow hardware-based timing without CPU intervention, reducing interrupt latency for safety-critical functions. Note: for full AEC-Q100 qualification, choose the automotive-grade variant.
Recommended
Medical / Health Monitoring Devices
The PIC18LF46K42-I/PT is well suited for low-power medical and wellness devices such as portable blood pressure monitors, pulse oximeters, and wearable fitness trackers. Its 1.8 V operation supports single-cell Li-ion or 2xAAA battery chemistries, while the 12-bit ADC with on-chip op-amps implements precision sensor signal chains for optical heart-rate sensing (PPG) or temperature measurement. The EEPROM stores patient calibration data, and the rich PWM and timer resources drive displays and buzzers. The XLP Sleep current below 50 nA extends battery life to weeks of continuous monitoring.
Recommended
Consumer Appliance / White Goods Control
In consumer appliances (washing machines, refrigerators, coffee machines, microwave ovens), the PIC18LF46K42-I/PT provides the I/O density, ADC resolution, and PWM channels required for motor control, temperature regulation, and user-interface management. The 12-bit ADC reads multiple thermistor and pressure-sensor inputs, while PWM drives triac phase-control or variable-frequency motor drivers. The CLC and DMA enable autonomous control loops without CPU load, improving responsiveness and reducing BOM cost. The 64 KB Flash supports graphical LCD menus and advanced feature firmware in C language.
Recommended
Smart Sensor / HVAC Building Automation
Building-automation HVAC sensors and controllers benefit from the PIC18LF46K42-I/PT's low-power operation and multiple communication interfaces. The device reads temperature, humidity, and CO2 sensors through its 12-bit ADC and I2C/SPI interfaces, then transmits data over Modbus, BACnet, or wireless mesh networks. The on-chip DAC and op-amps support 0-10 V analog output for legacy HVAC actuators, while the EEPROM stores calibration and configuration parameters. The wide 1.8 V-3.6 V supply allows direct 3.3 V operation from USB or 24 V systems with buck regulators.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF46K42-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF46K42-E/PT | PIC18F46K42-I/PT | PIC18LF46K40-I/PT | PIC18LF46K22-I/PT |
|---|---|---|---|---|---|
| Package | 44-pin TQFP (PT) 10x10mm | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Operating Voltage | 1.8 V to 3.6 V | 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 5.5 V |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB |
| CPU Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Temperature Range | -40C to +85C (I) | -40C to +125C (E) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) |
| ADC Resolution | 12-bit, 35 channels | 12-bit, 35 channels | 12-bit, 35 channels | 10-bit, fewer channels | 10-bit ADC |
| DMA / DAC | DMA + 5-bit DAC | DMA + 5-bit DAC | DMA + 5-bit DAC | No DMA, no DAC | No DMA, no DAC |
Key Differentiators
- 12-bit ADC2 with 35 channels vs older PIC18 families (vs PIC18LF46K22-I/PT)
- On-chip 5-bit DAC and DMA engine (vs PIC18LF46K40-I/PT)
- 1.8 V minimum supply for battery applications (vs PIC18F46K42-I/PT)
Design Notes
Decouple each VDD/AVDD pin with a 100 nF ceramic capacitor placed within 3 mm of the pin, plus a bulk 1-10 uF capacitor on the main VDD rail. For battery applications operating at 1.8 V, choose low-ESR ceramic capacitors (X5R or X7R) to maintain regulation under ADC sampling current transients. When using the internal regulator, leave the VCAP pin connected to a 1 uF capacitor to GND.
Place the 44-pin TQFP (PT) package on a 4-layer PCB with a continuous ground plane under the IC. Route the 64 MHz system clock trace as short as possible and avoid running parallel to analog ADC traces. Use a star-ground topology for AGND and DGND with a single tie-point near the MCU's AVSS/VSS pins to minimize digital switching noise coupling into the ADC measurements.
Do not leave unused I/O pins floating - configure them as outputs driving low or inputs with internal weak pull-ups using the UNUSED_PIN macro to prevent parasitic current draw. Always program the configuration bits to match your oscillator and watchdog requirements before code execution; an unconfigured WDT can cause unexpected resets. When migrating from PIC18F46K42 (5V) to LF46K42 (3.3V), verify all I/O interfaces for voltage compatibility to avoid damage to the LF variant's 3.6 V absolute maximum VDD.
For SPI communication above 8 MHz, place 33 ohm series resistors near the MCU's SCK and MOSI pins to dampen transmission-line reflections. When using I2C in standard or fast mode (100/400 kHz), keep total bus capacitance under 400 pF and use 4.7 kohm pull-ups at 3.3 V. For UART with LIN bus, ensure the LIN transceiver's master/slave configuration matches the firmware's UART initialization to avoid bus contention.
Compliance Information
RoHS compliant per Microchip product page. Not AEC-Q100 qualified - for automotive applications requiring AEC-Q100, choose the dedicated automotive-grade variant of the K42 family.