PIC18LF46K40-I/PT - 8-bit 64MHz 64KB Flash MCU | Microchip
MPN: PIC18LF46K40-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.45 | $3.45 |
| 10 | $3.07 | $30.70 |
| 100 | $2.65 | $265.00 |
| 500 | $2.32 | $1,160.00 |
| 1,000 | $2.1 | $2,100.00 |
PIC18LF46K40-I/PT Overview
What is an 8-bit PIC microcontroller? An 8-bit microcontroller is a single-chip computer with an 8-bit data path that executes instructions on one byte at a time. The PIC18 architecture from Microchip is a RISC (Reduced Instruction Set Computer) family that combines ease of programming, deterministic timing, and rich on-chip peripherals. Within the broader semiconductor hierarchy, microcontrollers sit alongside microprocessors as the building blocks of embedded systems; the PIC18 LF sub-family emphasizes eXtreme Low Power (XLP) operation, ideal for always-on IoT endpoints, sensor hubs, and portable medical devices where battery life dominates the BOM.
Key features include 36 digital I/O lines, 9 timers, 2 CCP modules, a 35-channel 10-bit ADC, multiple communication interfaces (I2C, SPI, UART with LIN support), and nanoWatt XLP technology with idle currents in the nanoampere range. The device supports both internal and external oscillator modes, in-circuit debugging via ICD, and operation across -40C to +85C industrial temperature range. Hardware CRC/SCAN and Windowed Watchdog Timer (WWDT) provide functional safety primitives for IEC 60730-class white-goods and consumer safety applications.
From an architectural standpoint, the PIC18LF46K40 uses a 16-bit instruction word with an 8-bit data path, allowing a 64 KB program memory address space with single-cycle Flash access at 64 MHz. The Core Independent Peripherals can chain deterministically (e.g., ADC-triggered PWM via CWG), removing jitter from software-driven loops. This is particularly valuable for motor control and power conversion, where timing jitter translates to audible noise or EMI.
Typical applications include low-power IoT sensor nodes, home appliances with touch and motor control, battery-powered medical monitors, industrial sensor hubs, and automotive body electronics (non-safety). Designers leverage the XLP sleep modes, peripheral pin select, and zero-cross detect to reduce BOM cost by eliminating external analog components. This PIC18LF46K40 variant targets designs that need the 44-pin TQFP footprint for roomy PCB layouts or for upgrade compatibility with larger pin-count PIC18LF45K40 designs.
For optimal results, follow the Microchip MPLAB X IDE configuration bits and use the MPLAB Code Configurator (MCC) to scaffold peripheral initialization. When migrating from PIC18LF45K40, verify that CCP and PWM mapping remain consistent with your PCB layout. Designers should always consult the Microchip PIC18(L)F26/45/46K40 datasheet for absolute maximum ratings and DC characteristics specific to the LF low-voltage variant.
This page synthesizes verified distributor pricing, same-family drop-in alternatives, and practical design notes beyond what is found in the manufacturer datasheet.
Drop-in alternatives for PIC18LF46K40-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 PIC18LF46K40-I/PT (same form factor and footprint) — differing in ADC, Package, Communication, Operating Temperature Range, Comparators.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF46K40-I/P
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF46K40T-I/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF46K40-E/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.05 / Unit
View Datasheet →PIC18F46K40-I/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18LF45K40-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.62 / Unit
View Datasheet →PIC18LF46K40-I/PT Maximum Ratings & Electrical Characteristics
| Product Family | PIC18 XLP 18K |
| Core Architecture | 8-bit PIC RISC |
| Program Memory (Flash) | 64 KB (32K x 16) |
| RAM | 3728 bytes |
| EEPROM | 1024 bytes |
| Maximum CPU Frequency | 64 MHz |
| Supply Voltage Range | 1.8 V to 3.6 V |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Digital I/O Pins | 36 |
| Number of Timers | 9 |
| ADC | 10-bit ADC2, up to 35 channels |
| DAC | 5-bit DAC |
| PWM Channels | 2 (16-bit) |
| Comparators | Yes |
| Package | 44-pin TQFP (PT) 10x10 mm |
| Mounting Type | Surface Mount |
| Communication | I2C, SPI, UART (with LIN) |
| Core Independent Peripherals | CWG, WWDT, CRC/SCAN, ZCD, HLT |
| RoHS Status | Compliant |
PIC18LF46K40-I/PT Pin Configuration
| Pin 1 | RA5 — I/O port A bit 5 |
| Pin 2 | RA4 — I/O port A bit 4 |
| Pin 3 | RA3 — I/O port A bit 3 |
| Pin 4 | RC1 — I/O port C bit 1 |
| Pin 5 | RC0 — I/O port C bit 0 |
| Pin 6 | RC6 — I/O port C bit 6 |
| Pin 7 | RC7 — I/O port C bit 7 |
| Pin 8 | RE3 — I/O port E bit 3 (input only on LF46K40) |
| Pin 9 | RE2 — I/O port E bit 2 |
| Pin 10 | RE1 — I/O port E bit 1 |
| Pin 11 | RE0 — I/O port E bit 0 |
| Pin 12 | VDD — Positive power supply |
| Pin 13 | VSS — Ground reference |
| Pin 14 | RB7 — I/O port B bit 7 |
| Pin 15 | RB6 — I/O port B bit 6 |
| Pin 16 | RB5 — I/O port B bit 5 |
| Pin 17 | RB4 — I/O port B bit 4 |
| Pin 18 | RB3 — I/O port B bit 3 |
| Pin 19 | RB2 — I/O port B bit 2 |
| Pin 20 | RB1 — I/O port B bit 1 |
| Pin 21 | RB0 — I/O port B bit 0 |
| Pin 22 | RD7 — I/O port D bit 7 |
| Pin 23 | RD6 — I/O port D bit 6 |
| Pin 24 | RD5 — I/O port D bit 5 |
| Pin 25 | RD4 — I/O port D bit 4 |
| Pin 26 | RC2 — I/O port C bit 2 |
| Pin 27 | RC3 — I/O port C bit 3 |
| Pin 28 | RC4 — I/O port C bit 4 |
| Pin 29 | RC5 — I/O port C bit 5 |
| Pin 30 | VSS — Ground reference |
| Pin 31 | VDD — Positive power supply |
| Pin 32 | RD0 — I/O port D bit 0 |
| Pin 33 | RD1 — I/O port D bit 1 |
| Pin 34 | RD2 — I/O port D bit 2 |
| Pin 35 | RD3 — I/O port D bit 3 |
| Pin 36 | RA7 — I/O port A bit 7 |
| Pin 37 | RA6 — I/O port A bit 6 |
| Pin 38 | RA1 — I/O port A bit 1 |
| Pin 39 | RA0 — I/O port A bit 0 |
| Pin 40 | RA2 — I/O port A bit 2 |
| Pin 41 | MCLR — Master clear (reset) input |
| Pin 42 | ICSPCLK — In-circuit serial programming clock |
| Pin 43 | ICSPDAT — In-circuit serial programming data |
| Pin 44 | VSS — Ground reference |
Typical Applications
PIC18LF46K40-I/PT is suitable for 6 applications: Battery-Powered IoT Sensor Node, Home Appliance Control with Touch and Motor Drive, Portable Medical Monitor, Industrial Sensor Hub and Process Transmitter, Automotive Body Electronics (Non-Safety), HVAC and Building Automation Controller.
Battery-Powered IoT Sensor Node
The PIC18LF46K40-I/PT is well suited for battery-powered IoT sensor nodes where idle current dominates battery life. Its XLP nanoWatt sleep modes deliver deep-sleep currents in the tens of nanoamperes while retaining RAM and peripheral state, and the 1.8V to 3.6V supply range accommodates a single Li-ion or 2xAA alkaline cell directly without a boost converter. Designers pair the 10-bit ADC2 with 35 analog channels to read multiple sensors via peripheral pin select, then wake on ADC threshold or comparator edge to transmit a measurement over UART or I2C. With 64 KB Flash and 3728 bytes RAM, the part comfortably hosts an MQTT-SN or LoRaWAN stack alongside application logic. Compared with a switching-power MCU, the LF XLP part avoids switching noise on analog inputs and reduces BOM cost by eliminating external op-amps for sensor conditioning.
Recommended
Home Appliance Control with Touch and Motor Drive
The PIC18LF46K40-I/PT integrates the peripherals needed for modern home appliances including washing machines, dishwashers, and induction cooktops. The Core Independent Peripherals - CWG, ZCD, and comparators - enable deterministic zero-cross switching for triac motor control without CPU intervention, reducing EMI and acoustic noise. The hardware Windowed Watchdog (WWDT) and CRC/SCAN provide functional safety primitives required for IEC 60730-class white-goods certification. Designers use the 5-bit DAC and 10-bit ADC2 to drive LED indicators and read temperature or humidity sensors, while the 16-bit PWM modules control valve solenoids and small DC motors. At 64 MHz CPU clock with single-cycle Flash access, the device handles user-interface scanning, sensor fusion, and motor commutation in a single part, reducing BOM cost by 30-50% compared with multi-chip architectures.
Recommended
Portable Medical Monitor
For portable medical monitors such as pulse oximeters, glucose meters, and wearable ECG patches, the PIC18LF46K40-I/PT delivers low-power operation, deterministic timing, and analog integration in a small footprint. Its XLP sleep mode below 50 nA enables multi-day battery life on a coin cell, while the 10-bit ADC2 with hardware averaging and oversampling supports accurate SpO2 or glucose measurements. The ZCD peripheral simplifies mains-frequency rejection for line-powered instrument front-ends. Designers benefit from hardware CRC for reliable firmware integrity and WWDT for safe operation if firmware hangs. The 44-pin TQFP package provides ample I/O for displays, pushbuttons, and Bluetooth HCI bridging to external radios.
Recommended
Industrial Sensor Hub and Process Transmitter
The PIC18LF46K40-I/PT fits industrial 4-20 mA process transmitters, RTU sensor hubs, and Modbus slave nodes thanks to its industrial -40C to +85C temperature range and CIPs that operate deterministically without CPU load. Its UART with LIN support, plus I2C and SPI, allows simultaneous connection to multiple field sensors and a host PLC. The hardware CRC/SCAN protects configuration memory against bit flips in electrically noisy industrial cabinets, while WWDT triggers a safe reset if firmware locks up. With 64 KB Flash, designers embed Modbus RTU, HART, or IO-Link device stacks alongside application logic. The 44-pin TQFP package supports up to 36 I/O, enabling direct connection to multiple analog sensor inputs without external mux ICs.
Recommended
Automotive Body Electronics (Non-Safety)
For automotive body electronics such as seat controllers, mirror adjusters, and ambient lighting, the PIC18LF46K40-I/PT offers LIN bus support via the UART peripheral and sufficient Flash for LIN device stacks. Designers use the 16-bit PWM modules to drive LED arrays with smooth dimming curves, and the CWG generates complementary drive signals for small DC motor bridges. While the I-grade variant is rated -40C to +85C for cabin environments, automotive designers targeting underhood or extreme cold should consider the E-grade variant. The PIC18LF46K40-I/PT is not AEC-Q100 qualified, so it is suited to non-safety body electronics only; safety-critical systems require AEC-Q100 parts such as the PIC18F46K40-I/PT automotive-grade family members.
Recommended
HVAC and Building Automation Controller
The PIC18LF46K40-I/PT serves as a flexible HVAC controller for thermostats, fan-coil units, and VAV box actuators. The 10-bit ADC2 reads multiple temperature sensors and potentiometers, while the comparators detect zero-cross events on the AC mains for triac-based heater switching without external circuitry. Designers leverage the CWG and 16-bit PWM for variable-speed fan control with quiet acoustic performance. With 64 KB Flash, the part hosts BACnet MS/TP or Modbus device firmware alongside scheduling logic. The 1.8V to 3.6V supply allows direct operation from a 3.3V LDO fed from a 24VAC wall adapter, simplifying the BOM. Designers adding wireless connectivity pair the PIC18LF46K40-I/PT with an external radio via SPI or UART.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF46K40-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF46K40T-I/PT | PIC18LF46K40-E/PT | PIC18F46K40-I/PT | PIC18LF45K40-I/PT |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-pin TQFP (PT) 10x10 mm | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same | 44-pin TQFP (PT) - same |
| Program Memory (Flash) | 64 KB | 64 KB | 64 KB | 64 KB | 32 KB |
| RAM | 3728 bytes | 3728 bytes | 3728 bytes | 3728 bytes | 2048 bytes |
| Supply Voltage | 1.8 V to 3.6 V (LF) | 1.8 V to 3.6 V | 1.8 V to 3.6 V | 2.3 V to 5.5 V (F) | 1.8 V to 3.6 V |
| Operating Temperature | -40 C to +85 C (I-grade) | -40 C to +85 C | -40 C to +125 C (E-grade) | -40 C to +85 C | -40 C to +85 C |
| Maximum CPU Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Digital I/O Pins | 36 | 36 | 36 | 36 | 36 |
| ADC Resolution | 10-bit (35 channels) | 10-bit (35 channels) | 10-bit (35 channels) | 10-bit (35 channels) | 10-bit (35 channels) |
| EEPROM | 1024 bytes | 1024 bytes | 1024 bytes | 1024 bytes | 1024 bytes |
Key Differentiators
- Largest Flash in the 44-pin PIC18 K40 family at 64 KB (vs PIC18LF45K40-I/PT)
- Lowest operating voltage in the family at 1.8V (vs PIC18F46K40-I/PT)
- Full Core Independent Peripheral suite including ZCD and CWG (vs PIC18LF25K80-I/SP)
Design Notes
Place a 100 nF decoupling capacitor within 3 mm of each VDD pin (pins 12 and 31) and a 10 uF bulk capacitor at the board power entry. The LF variant operates down to 1.8V, so verify that the LDO or DC-DC regulator supplying the part maintains output above 1.8V under full load transients. Estimated: total quiescent current of the MCU in Sleep mode with ADC off is below 50 nA per the Microchip PIC18 K40 family datasheet, allowing years of operation on a CR2032 coin cell with duty-cycled sensor reads.
Use a 4-layer PCB with a dedicated ground plane under the TQFP package to minimize EMI and improve ADC accuracy. Keep analog signal traces short and away from switching nodes; the on-chip ZCD peripheral requires a clean AC mains reference for triac control, so add a 100 ohm series resistor on the ZCD input pin. Place the 32.768 kHz or 20 MHz crystal within 5 mm of OSC1/OSC2 with a grounded copper guard ring. Estimated: 50 mm distance between analog traces and switching nodes typically achieves >60 dB crosstalk attenuation.
Do not exceed the absolute maximum VDD of 4.0V on the LF variant or 5.5V on the F variant; transient spikes from motor loads or inductors must be clamped with TVS diodes. Configuration bits must be set correctly for the chosen oscillator mode; a common mistake is leaving the PLL disabled when targeting 64 MHz operation. The ICD pins (ICSPCLK/ICSPDAT, pins 42/43) require isolation from any circuitry driving those pins during programming, or programming will fail. Always enable the WWDT in production firmware for IEC 60730-class safety.
When using the CWG peripheral for complementary PWM output, add 100 ohm series resistors at the CWG output pins to dampen ringing on long PCB traces to MOSFET gates. For SPI communications at >4 MHz, add a 33 ohm series resistor near the source pin to reduce reflections. The I2C pins require external 4.7k pull-up resistors for reliable operation above 100 kHz; the internal weak pull-ups are insufficient for production designs.
Compliance Information
RoHS and REACH compliant per Microchip product page. Not AEC-Q100 qualified - the I/PT industrial variant is rated -40C to +85C. For automotive applications requiring AEC-Q100, select an automotive-grade PIC18F46K40 family variant. Lead-free and halogen-free per Microchip material declarations.