PIC18F46K40-E/ML - 8-Bit 64KB Flash MCU, 64MHz, 44-QFN | Microchip
MPN: PIC18F46K40-E/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.95 | $2.95 |
| 10 | $2.65 | $26.50 |
| 100 | $2.36 | $236.00 |
| 500 | $2.12 | $1,060.00 |
| 1,000 | $1.89 | $1,890.00 |
PIC18F46K40-E/ML Overview
A microcontroller (MCU) is an integrated circuit that combines a CPU core, non-volatile program memory, working RAM, and a rich set of on-chip peripherals such as timers, ADC, communication interfaces, and GPIO. The PIC18 family is Microchip's 8-bit architecture, optimized for low-power, deterministic embedded control. Microcontrollers sit below microprocessors in complexity but above simple logic ICs in capability, serving as the 'brain' of nearly every embedded product from appliances to industrial nodes.
Key features include a 10-bit ADC with computation (ADC2), a 5-bit DAC, two comparators, multiple PWM/CCP/CWG channels, a hardware Limit Timer (HLT), a Windowed Watchdog Timer (WWDT), and a CRC/SCAN module for memory integrity monitoring. The 64MHz internal oscillator, 49 I/O pins, and support for EUSART, I2C, and SPI make it suitable for sensor hubs, human-machine interfaces, and motor control loops. XLP technology delivers nanoWatt sleep currents in the single-digit µA range, ideal for battery-backed or energy-harvesting designs.
Architecturally, the PIC18F46K40-E/ML uses an 8-bit RISC Harvard core with 16-bit instructions and a hardware multiplier, backed by 64KB self-programmable Flash (32K x 16 words), 4KB RAM, and 256 bytes of EEPROM. The Core Independent Peripherals (CIPs) - CWG, DSM, CLC, HLT, and WWDT - execute complex sequences without CPU intervention, freeing the core for application logic and enabling deterministic real-time response.
Typical applications include IoT sensor nodes, building automation, white goods and small appliance control, lighting controllers, low-end motor and fan control, USB-to-UART bridges, and battery-powered instrumentation. The wide 2.3V-5.5V supply range supports both 3.3V and 5V rails, simplifying integration into mixed-voltage systems. When designing with this device, allocate the exposed pad (EP) to a continuous copper pour on the PCB to reduce thermal resistance and improve EMI performance; an unbroken ground plane under the EP is the recommended layout.
Drop-in alternatives for PIC18F46K40-E/ML — 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 PIC18F46K40-E/ML (same form factor and footprint) — differing in ADC, Comparators, I/O Pins, Package, DAC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F46K40T-E/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F46K40-I/ML
✅ Drop-In✓ In Stock
$2.55 / Unit
View Datasheet →PIC18F46K42-E/ML
✅ Drop-In✓ In Stock
$1.95 / Unit
View Datasheet →PIC18F46K40-E/PT
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F47K40-E/ML
✅ Drop-In✓ In Stock
$2.67 / Unit
View Datasheet →PIC18F46K40-E/ML Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC |
| Program Memory (Flash) | 64 KB (32K x 16 words) |
| Data RAM | 4 KB |
| Data EEPROM | 256 B |
| Maximum CPU Frequency | 64 MHz |
| Supply Voltage (Vdd) | 2.3 V to 5.5 V |
| Operating Temperature Range | -40 C to +125 C (E suffix) |
| I/O Pins | 36 (high-current capable) |
| ADC | 10-bit ADC2 with Computation |
| DAC | 5-bit DAC |
| Comparators | 2 |
| PWM / CCP / CWG | Yes (multiple channels, includes Complementary Waveform Generator) |
| Windowed Watchdog Timer (WWDT) | Yes |
| Hardware Limit Timer (HLT) | Yes |
| CRC / Memory Scan | Yes |
| Communication Interfaces | EUSART, I2C, SPI |
| Package | 44-pin QFN (PQFN, 8x8 mm) with exposed pad |
| Mounting Type | Surface Mount |
| MSL Level | 3 (168 hours, reflow 260 C) |
| RoHS Status | RoHS3 Compliant |
PIC18F46K40-E/ML Pin Configuration
| Pin 1 | RA2 — Port A bit 2, analog/digital I/O |
| Pin 2 | RA3 — Port A bit 3, analog/digital I/O |
| Pin 3 | RA4 — Port A bit 4, analog/digital I/O |
| Pin 4 | RA5 — Port A bit 5, analog/digital I/O |
| Pin 5 | RA6 — Port A bit 6, analog/digital I/O |
| Pin 6 | RA7 — Port A bit 7, analog/digital I/O |
| Pin 7 | Vss — Ground reference |
| Pin 8 | Vdd — Positive supply voltage (2.3V-5.5V) |
| Pin 9 | OSC1 — Crystal oscillator input / external clock input |
| Pin 10 | OSC2 — Crystal oscillator output |
| Pin 11 | RC0 — Port C bit 0, digital I/O |
| Pin 12 | RC1 — Port C bit 1, digital I/O |
| Pin 13 | RC2 — Port C bit 2, digital I/O |
| Pin 14 | RC3 — Port C bit 3, digital I/O |
| Pin 15 | RC4 — Port C bit 4, digital I/O |
| Pin 16 | RC5 — Port C bit 5, digital I/O |
| Pin 17 | RC6 — Port C bit 6, digital I/O |
| Pin 18 | RC7 — Port C bit 7, digital I/O |
| Pin 19 | Vss — Ground reference |
| Pin 20 | Vdd — Positive supply voltage (2.3V-5.5V) |
| Pin 21 | RB0 — Port B bit 0, digital I/O, interrupt-on-change |
| Pin 22 | RB1 — Port B bit 1, digital I/O, interrupt-on-change |
| Pin 23 | RB2 — Port B bit 2, digital I/O, interrupt-on-change |
| Pin 24 | RB3 — Port B bit 3, digital I/O, interrupt-on-change |
| Pin 25 | RB4 — Port B bit 4, digital I/O, interrupt-on-change |
| Pin 26 | RB5 — Port B bit 5, digital I/O, interrupt-on-change |
| Pin 27 | RB6 — Port B bit 6, digital I/O, ICSPCLK |
| Pin 28 | RB7 — Port B bit 7, digital I/O, ICSPDAT |
| Pin 29 | Vss — Ground reference |
| Pin 30 | Vdd — Positive supply voltage (2.3V-5.5V) |
| Pin 31 | RD0 — Port D bit 0, digital I/O |
| Pin 32 | RD1 — Port D bit 1, digital I/O |
| Pin 33 | RD2 — Port D bit 2, digital I/O |
| Pin 34 | RD3 — Port D bit 3, digital I/O |
| Pin 35 | RD4 — Port D bit 4, digital I/O |
| Pin 36 | RD5 — Port D bit 5, digital I/O |
| Pin 37 | RD6 — Port D bit 6, digital I/O |
| Pin 38 | RD7 — Port D bit 7, digital I/O |
| Pin 39 | RE0 — Port E bit 0, digital I/O |
| Pin 40 | RE1 — Port E bit 1, digital I/O |
| Pin 41 | RE2 — Port E bit 2, digital I/O |
| Pin 42 | RE3 — Port E bit 3, digital I/O |
| Pin 43 | AVss — Analog ground reference |
| Pin 44 | AVdd — Analog positive supply (2.3V-5.5V) |
Typical Applications
PIC18F46K40-E/ML is suitable for 6 applications: IoT Sensor Node, Building Automation Controller, White Goods and Small Appliance Control, LED Lighting Controller, Low-End BLDC Fan and Pump Motor Control, USB-to-UART Bridge and Industrial Connectivity Module.
IoT Sensor Node
The PIC18F46K40-E/ML is well matched to IoT sensor nodes thanks to its XLP nanoWatt sleep modes drawing typically under 1 µA in deep sleep with RTCC running, plus its 10-bit ADC2 with computation that offloads averaging and threshold detection from the core. The 64KB Flash accommodates protocol stacks such as Modbus RTU or lightweight LoRaWAN device drivers, and the integrated 5V-tolerant I/O simplifies interfacing with industrial sensors. EUSART plus I2C/SPI enables connection to radios, sensors, and EEPROM. The exposed thermal pad on the 44-QFN package reduces junction-to-ambient thermal resistance to roughly 31 C/W, allowing continuous ADC sampling at high ambient temperatures without throttling. In a typical 4-20 mA current-loop sensor, the MCU digitizes the loop voltage, applies ADC2 hardware averaging, and transmits via UART every few seconds before returning to sleep.
Recommended
Building Automation Controller
The PIC18F46K40-E/ML fits building automation controllers such as HVAC zone controllers, BACnet/Modbus gateway nodes, and lighting control panels. The 64MHz core, 4KB RAM, and 64KB Flash run real-time control loops while EUSART, I2C, and SPI handle fieldbus transceivers, keypads, and displays. The Complementary Waveform Generator (CWG) and PWM channels drive TRIAC or MOSFET dimmers for LED lighting without software timing jitter. The 5V tolerance allows direct interface with legacy 0-10 V lighting control signals and 24 VAC-powered sensors. CRC/SCAN hardware monitors flash integrity at every startup, important for safety-critical building systems. The extended -40C to +125C operating range ensures reliability in unconditioned mechanical rooms and outdoor enclosures.
Recommended
White Goods and Small Appliance Control
Washing machines, dishwashers, refrigerators, microwave ovens, and coffee machines benefit from the PIC18F46K40-E/ML's combination of robust peripherals, 5V operation, and extended temperature range. The Hardware Limit Timer (HLT) and Windowed Watchdog Timer (WWDT) provide functional safety features typically required by IEC 60730 Class B appliance standards, while the 2 comparators handle zero-crossing detection on AC mains and motor current sensing. The CWG drives motor-control MOSFETs directly with hardware dead-band generation, offloading the CPU for energy-efficient BLDC or universal-motor control. With 36 I/O pins, the MCU interfaces directly with keypads, seven-segment displays, LCD modules, and triac drivers without external glue logic. The 64KB Flash is sufficient for full-featured appliance firmware including user-interface handling, sensor fusion, and safety-state machines.
Recommended
LED Lighting Controller
The PIC18F46K40-E/ML suits architectural and commercial LED lighting controllers requiring smooth dimming, color mixing, and DMX/DALI-style network connectivity. The Complementary Waveform Generator produces complementary PWM outputs with programmable dead time and blanking, ideal for high-frequency LED driver stages up to several hundred kHz. The 5-bit DAC and PWM channels support up to 16-bit effective dimming resolution through dithering, eliminating visible flicker in cinematography-grade applications. The 10-bit ADC2 monitors LED current via sense resistors, enabling closed-loop brightness and color-temperature regulation. The XLP low-power modes allow battery-powered or energy-harvested lighting sensors that wake the controller only on motion or ambient light changes, achieving years of operation on a single cell.
Recommended
Low-End BLDC Fan and Pump Motor Control
Compact BLDC fans, blowers, and small pumps benefit from the PIC18F46K40-E/ML's integrated motor-control peripherals: the CWG, the hardware HLT (limit timer for overcurrent protection), and two on-chip comparators for back-EMF sensing. The 64MHz core provides enough compute headroom for sensorless trapezoidal commutation and closed-loop speed control, while the CWG hardware generates the complementary PWM with dead-band insertion, freeing the CPU to handle the commutation state machine. The Windowed Watchdog Timer protects against firmware stalls that could otherwise stall the motor in a partially-commutated state. Operating from 2.3V to 5.5V allows direct connection to 3.3V or 5V gate drivers such as the MCP8026, simplifying the BOM and shrinking the PCB.
Recommended
USB-to-UART Bridge and Industrial Connectivity Module
The PIC18F46K40-E/ML serves as a low-cost USB-to-UART/SPI/I2C bridge module for industrial equipment retrofits, debug consoles, and field-service adapters. The on-chip EUSART, I2C, and SPI peripherals connect to legacy equipment, while the MCU re-formats traffic onto a higher-level protocol or forwards it over USB using an external transceiver such as the MCP2200 or MCP2221. The 64KB Flash stores protocol translation tables for Modbus RTU, NMEA 0183, or custom command sets, and 4KB of RAM buffers transient bursts. The hardware CRC/SCAN engine ensures firmware integrity in field-deployed modules, an important consideration for industrial security. The wide 2.3V-5.5V supply range supports both 3.3V USB-powered designs and 5V RS-232/RS-485 systems.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F46K40-E/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F46K40T-E/ML | PIC18F46K40-I/ML | PIC18F46K42-E/ML | PIC18F46K40-E/PT | PIC18F47K40-E/ML |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 44-QFN (8x8 mm) | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | 44-TQFP - same pinout, different package | 44-QFN (8x8 mm) - same |
| Flash Memory | 64 KB | 64 KB | 64 KB | 64 KB | 64 KB | 128 KB |
| Data RAM | 4 KB | 4 KB | 4 KB | 4 KB | 4 KB | 8 KB |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Maximum Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating Temperature | -40 C to +125 C (E) | -40 C to +125 C (E) | -40 C to +85 C (I) | -40 C to +125 C (E) | -40 C to +125 C (E) | -40 C to +125 C (E) |
| Supply Voltage | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V | 2.3 V to 5.5 V |
Key Differentiators
- Higher Flash and RAM headroom in the same QFN footprint (vs PIC18F46K40-E/PT (TQFP variant))
- Extended -40 C to +125 C automotive/industrial temperature range (vs PIC18F46K40-I/ML (industrial grade))
- Tape-and-reel packaging for automated high-volume assembly (vs PIC18F46K40-E/ML (tube))
Design Notes
The 44-QFN (8x8 mm) package relies on its exposed thermal pad for heat removal; solder this pad to a continuous copper pour of at least 1 square inch on the top layer, with multiple thermal vias to the inner ground plane. Without this, junction-to-ambient thermal resistance rises well above the datasheet's ~31 C/W figure, causing premature thermal shutdown when the ADC and CWG operate continuously at 64MHz in industrial enclosures at +85 C or higher.
Place a 100 nF decoupling capacitor as close as possible to each Vdd pin (the PIC18F46K40-E/ML has four Vdd pins at positions 8, 20, 30, and analog AVdd at 44). Add a bulk 10 µF ceramic or tantalum near the MCU. According to the Microchip datasheet, AVdd may be tied to Vdd for simple designs, but for ADC accuracy better than 8 bits, isolate AVdd with an LC or ferrite-bead filter to suppress digital switching noise from the core and I/O transitions.
Do not leave the MCLR pin floating - it must be tied to Vdd through a 10 kΩ pull-up for normal operation, and optionally a tactile reset switch to ground. Floating MCLR is the most common cause of spurious resets and erratic behavior on PIC18 K40 designs. According to Microchip's PIC18F46K40 datasheet, an internal weak pull-up is available but is too weak to guarantee clean resets in electrically noisy industrial environments.
Route the ICSP clock (RB6/ICSPCLK) and data (RB7/ICSPDAT) lines directly to an in-circuit programming header with no series resistors and minimal stubs. Keeping these traces short ensures reliable field firmware upgrades, especially on populated production boards. According to Microchip's programming specifications, long traces or stubs greater than 50 mm can cause ICSP failures; add a 4.7 kΩ pull-up on MCLR to the ICSP header to allow in-system programming without manual reset.
Compliance Information
RoHS3 compliant per Microchip product page. Not AEC-Q100 qualified - the -E temperature grade alone is not automotive qualification. For AEC-Q100 automotive designs, see Microchip's PIC18F46K40-E/MLVAO or contact the manufacturer.
