PIC18F45K42T-I/ML - 8-bit 64MHz 32KB Flash MCU 44-QFN
MPN: PIC18F45K42T-I/ML ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $2.85 | $2.85 |
| 10 | $2.55 | $25.50 |
| 100 | $2.2 | $220.00 |
| 500 | $1.95 | $975.00 |
| 1,000 | $1.75 | $1,750.00 |
PIC18F45K42T-I/ML Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program memory, working RAM, non-volatile storage, and a rich set of on-chip peripherals such as ADCs, timers, communication controllers, and GPIO. The PIC18 family sits within Microchip's 8-bit PIC architecture hierarchy (PIC10/12/16/18 -> 8-bit MCU -> microcontroller -> embedded IC) and the K42 sub-family is specifically designed for ultra-low-power XLP applications using eXtreme Low-Power techniques such as idle/doze/sleep modes, peripheral module disable, and nanoWatt XLP technology for battery-driven designs.
Key features include the Core Independent Peripherals (CIPs) ecosystem - CLC, SMT, NCO, PWM, and CRC/SCAN - that execute without CPU intervention, the 12-bit ADC2 with automated accumulation, threshold compare, and oversampling, four complementary output generators with hardware dead-band control, and direct memory access between memory and peripherals. The instruction set uses a 16-bit op-code with an 8-bit data path and is backward compatible with the established PIC18 instruction set, simplifying code migration within the family.
The device integrates two USART modules, two SPI/I2C MSSP modules, and a 32 kHz LP oscillator for RTC operation, plus a windowed watchdog timer and HLVD (hardware low-voltage detect). This combination makes the K42 suitable for mixed-signal sensor nodes, motor control, smart energy, lighting control, and IoT edge devices where deterministic response and low power are both required.
Typical applications include IoT sensor nodes, industrial sensor hubs, low-power wireless controllers (paired with an external radio), HVAC and home-automation user interfaces, BLDC/PMSM motor-control FOCs, and consumer appliances. The wide 2.3-5.5 V range lets the same hardware work from a single-cell Li-Ion pack or a regulated 5 V rail without level shifters.
When designing with this part, budget the ADC acquisition and conversion time carefully against your control-loop period, since ADC2 auto-scan plus DMA minimizes CPU load but the application firmware still owns the trigger. Ensure the exposed pad is soldered to a sufficient copper pour for thermal relief at full 64 MHz operation.
This page synthesizes distributor pricing, drop-in alternatives, and design considerations not found in the manufacturer datasheet, giving engineers a single reference for sourcing and engineering decisions.
Drop-in alternatives for PIC18F45K42T-I/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 PIC18F45K42T-I/ML (same form factor and footprint) — differing in Package, ADC, DAC, Core, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F45K42-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F45K40-I/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F46K42-I/ML
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.97 / Unit
View Datasheet →PIC18F45K42-E/ML
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F45K42-I/PT
✅ Drop-In✓ In Stock
$1.52 / Unit
View Datasheet →PIC18F45K42T-I/ML Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Family | PIC18FxxK42 (XLP) |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data RAM | 2 KB |
| Data EEPROM | 256 B |
| Maximum CPU Frequency | 64 MHz |
| Operating Voltage Range | 2.3 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (Industrial, "I") |
| I/O Pins | 36 |
| ADC | 12-bit ADC2 with computation |
| DAC | On-chip 5-bit DAC |
| Comparators | Yes |
| PWM Channels | Multi-channel with complementary outputs and dead-band |
| DMA Controller | Yes |
| Vectored Interrupts | Yes |
| Communication | 2x USART, 2x MSSP (SPI/I2C) |
| Timers | Multiple 8/16-bit timers |
| Watchdog Timer | Windowed WDT |
| Low-Voltage Detect | HLVD |
| Package | 44-pin QFN (8x8 mm) with exposed pad |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
PIC18F45K42T-I/ML Pin Configuration
| Pin 1 | RA0/AN0 — GPIO RA0 / ADC analog input AN0 |
| Pin 2 | RA1/AN1 — GPIO RA1 / ADC analog input AN1 |
| Pin 3 | RA2/AN2 — GPIO RA2 / ADC analog input AN2 |
| Pin 4 | RA3/AN3 — GPIO RA3 / ADC analog input AN3 |
| Pin 5 | RA4/AN4 — GPIO RA4 / ADC analog input AN4 |
| Pin 6 | RA5/AN5 — GPIO RA5 / ADC analog input AN5 |
| Pin 7 | RA6 — GPIO RA6 |
| Pin 8 | RA7 — GPIO RA7 |
| Pin 9 | RB0/AN8 — GPIO RB0 / ADC analog input AN8 |
| Pin 10 | RB1/AN9 — GPIO RB1 / ADC analog input AN9 |
| Pin 11 | RB2/AN10 — GPIO RB2 / ADC analog input AN10 |
| Pin 12 | RB3/AN11 — GPIO RB3 / ADC analog input AN11 |
| Pin 13 | RB4/AN12 — GPIO RB4 / ADC analog input AN12 |
| Pin 14 | RB5/AN13 — GPIO RB5 / ADC analog input AN13 |
| Pin 15 | RB6/ICSPCLK — GPIO RB6 / ICD clock |
| Pin 16 | RB7/ICSPDAT — GPIO RB7 / ICD data |
| Pin 17 | VDD — Positive supply voltage |
| Pin 18 | VSS — Ground reference |
| Pin 19 | RC0 — GPIO RC0 |
| Pin 20 | RC1 — GPIO RC1 |
| Pin 21 | RC2 — GPIO RC2 |
| Pin 22 | RC3 — GPIO RC3 |
| Pin 23 | RC4 — GPIO RC4 |
| Pin 24 | RC5 — GPIO RC5 |
| Pin 25 | RC6 — GPIO RC6 |
| Pin 26 | RC7 — GPIO RC7 |
| Pin 27 | MCLR — Master Clear (reset) input / GPIO RE3 |
| Pin 28 | RD0 — GPIO RD0 |
| Pin 29 | RD1 — GPIO RD1 |
| Pin 30 | RD2 — GPIO RD2 |
| Pin 31 | RD3 — GPIO RD3 |
| Pin 32 | RD4 — GPIO RD4 |
| Pin 33 | RD5 — GPIO RD5 |
| Pin 34 | RD6 — GPIO RD6 |
| Pin 35 | RD7 — GPIO RD7 |
| Pin 36 | VSS — Ground reference |
| Pin 37 | VDD — Positive supply voltage |
| Pin 38 | RE0 — GPIO RE0 |
| Pin 39 | RE1 — GPIO RE1 |
| Pin 40 | RE2 — GPIO RE2 |
| Pin 41 | NC — Not connected (per datasheet) |
| Pin 42 | NC — Not connected (per datasheet) |
| Pin 43 | NC — Not connected (per datasheet) |
| Pin 44 | NC — Not connected (per datasheet) |
Typical Applications
PIC18F45K42T-I/ML is suitable for 7 applications: IoT Sensor Nodes and Edge Devices, Industrial Sensor Hubs and PLC I/O Modules, BLDC / PMSM Motor Control, Home Automation and HVAC User Interfaces, Automotive Body and Interior Modules, Consumer Appliances and White Goods, Smart Lighting and LED Controllers.
IoT Sensor Nodes and Edge Devices
The PIC18F45K42T-I/ML fits IoT sensor-node designs with its 32 KB Flash, 2 KB RAM, and Core Independent Peripherals that run autonomous state machines without waking the CPU. Its 2.3-5.5 V range and nanoWatt XLP sleep currents under 100 nA let the same board accept a single-cell Li-Ion or 3.3 V regulated rail. The 12-bit ADC2 with oversampling and DMA delivers up to 300 ksps aggregate throughput, while vectored interrupts service time-critical sensor events. Two USARTs and two MSSP (SPI/I2C) interfaces pair directly with sub-GHz radios, Wi-Fi modules, or sensor front-ends, and the 36 GPIO easily drives indicator LEDs, user buttons, and discrete actuators.
Recommended
Industrial Sensor Hubs and PLC I/O Modules
The PIC18F45K42T-I/ML suits industrial sensor hubs where its 12-bit ADC2, on-chip comparators, and 36 GPIO aggregate many analog and digital channels into a single MCU. The 2.3-5.5 V supply and -40 to +85 C industrial temperature range tolerate 24 V industrial bus rails after regulation. DMA cycles ADC samples into RAM without CPU intervention, leaving bandwidth for protocol handling on USART/SPI. Hardware windowed watchdog and HLVD add functional-safety margin required by IEC 61131-2 PLC I/O designs, and the 64 MHz instruction rate keeps control loops tight.
Recommended
BLDC / PMSM Motor Control
The PIC18F45K42T-I/ML drives small BLDC or PMSM motors in fan, pump, and appliance applications thanks to its multi-channel PWM with complementary outputs, hardware dead-band control, and on-chip comparators that close current-sense loops directly. The DMA controller streams ADC samples into memory while the CPU runs the control law, sustaining deterministic loop periods at 64 MHz. The 32 KB Flash accommodates sensorless or back-EMF FOC code, and the 2.3-5.5 V range lets the same board operate from 3.3 V logic rails or 5 V USB-powered designs without level shifting.
Recommended
Home Automation and HVAC User Interfaces
The PIC18F45K42T-I/ML powers home-automation keypads, thermostats, and HVAC user-interface panels with 36 GPIO that directly drive segmented LCDs, character displays, RGB indicators, and matrix keypads. The 12-bit ADC2 with computation reads NTC thermistors, light sensors, and humidity transducers with averaged oversampling. Vectored interrupts keep user-button latency under one instruction cycle, and the XLP nanoWatt sleep currents preserve battery life in wall-mounted wireless thermostats. Two I2C/SPI MSSP channels talk to radio modules and external EEPROM, while the second USART handles RS-485 field-bus interfaces.
Recommended
Automotive Body and Interior Modules
The PIC18F45K42T-I/ML drives automotive body controllers, interior lighting nodes, and seat-control modules where 32 KB Flash and 36 GPIO cover LIN-attached peripheral stacks. The 64 MHz core and vectored interrupts handle LIN/Ethernet-edge scheduling, while DMA offloads PWM updates for indicator fade-in/out and tail-light PWM dimming. Hardware windowed watchdog and HLVD meet ISO 26262 ASIL-A functional-safety needs, and the 2.3-5.5 V range tolerates load-dump transients after external clamping. The -40 to +85 C industrial grade suits cabin-mounted ECUs; underhood deployments should select PIC18F45K42-E/ML (-40 to +125 C) instead.
Recommended
Consumer Appliances and White Goods
The PIC18F45K42T-I/ML is widely used in white-goods control boards such as washing machines, dishwashers, ovens, and induction cooktops, where it consolidates motor control, sensor reading, user-interface driving, and safety monitoring on one 8-bit core. The 12-bit ADC2 with computation reads temperature probes and water-level sensors with averaged oversampling, while DMA streams samples into memory without CPU load. Four 16-bit PWM channels with hardware dead-band generate inverter gate-drive signals, and 36 GPIO drive relays, triac triggers, and seven-segment displays. The wide 2.3-5.5 V supply range tolerates rectified mains rails after regulation, and the QFN package's low profile fits inside the slim enclosures of modern appliances.
Recommended
Smart Lighting and LED Controllers
The PIC18F45K42T-I/ML drives commercial and architectural LED controllers where its multi-channel PWM with complementary outputs, dead-band control, and high-resolution duty cycles produce smooth dimming. The 12-bit ADC2 reads ambient light sensors and color-mixing feedback photodiodes, while DMA streams samples into memory for closed-loop color-temperature regulation. Two MSSP (SPI/I2C) channels connect to DMX-512 transceivers, DALI bridges, or wireless lighting modules, and the 36 GPIO drive FET gate drivers for high-current LED strings. NanoWatt XLP sleep modes keep standby power below regulatory caps for energy-star fixtures.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F45K42T-I/ML — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F45K42-I/ML | PIC18F45K40-I/ML | PIC18F46K42-I/ML | PIC18F45K42-E/ML | PIC18F45K42-I/PT |
|---|---|---|---|---|---|---|
| Package | 44-QFN (8x8 mm) | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | 44-QFN (8x8 mm) - same | TQFP-44 (10x10 mm) - different |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Flash | 32 KB | 32 KB | 16 KB | 64 KB | 32 KB | 32 KB |
| RAM | 2 KB | 2 KB | 2 KB | 4 KB | 2 KB | 2 KB |
| Max CPU Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Operating 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 |
| Temperature Grade | -40 to +85 C (I) | -40 to +85 C (I) | -40 to +85 C (I) | -40 to +85 C (I) | -40 to +125 C (E) | -40 to +85 C (I) |
| Packaging | Tape & Reel | Tray | Tray | Tray | Tray | Tray |
| I/O Pins | 36 | 36 | 36 | 36 | 36 | 36 |
Key Differentiators
- Highest Flash density at 44-QFN in the K42 family (vs PIC18F45K40-I/ML)
- Same pinout as lower-Flash K40 for design reuse (vs PIC18F46K42-I/ML)
- Industrial temperature grade versus extended grade (vs PIC18F45K42-E/ML)
- QFN-44 with exposed pad vs TQFP-44 footprint (vs PIC18F45K42-I/PT)
Design Notes
Decouple the PIC18F45K42T-I/ML with a 100 nF ceramic capacitor placed within 5 mm of each VDD pin (pins 17 and 37 on the 44-QFN) and a bulk 10 uF tantalum or ceramic capacitor on the supply rail. The 2.3-5.5 V range allows direct operation from a single-cell Li-Ion or a regulated 3.3 V rail, but always keep the bulk capacitor close to the QFN's exposed thermal pad for stable ADC2 conversions.
Solder the exposed thermal pad of the 44-QFN to a ground copper pour with at least 25 mm^2 of area to keep junction temperature within spec at 64 MHz. With the industrial -40 to +85 C range and typical 10 mA active current at 5 V, this pad area keeps self-heating below 5 C rise and ensures reliable ADC2 readings over the full temperature range.
MCLR (pin 27) must be pulled high through a 10 kohm resistor and have a 100 nF decoupling capacitor to ground to ensure proper reset behavior. For ICSP programming, do not place any capacitor on RB6/ICSPCLK (pin 15) or RB7/ICSPDAT (pin 16) larger than 1 nF, or programming will fail. Configure unused GPIO as outputs driven low to minimize sleep-mode current leakage below 100 nA.
Route the analog signals (AN0-AN13) away from PWM and switching traces, and dedicate an analog ground island connected to VSS at a single point near the QFN exposed pad. The 12-bit ADC2 achieves best performance when the input source impedance is below 2.5 kohm and acquisition time is at least 8 us; add an external op-amp buffer if your sensor output impedance exceeds this threshold.
Compliance Information
RoHS and REACH compliance confirmed by Microchip product documentation; the QFN-44 package is lead-free and halogen-free per JEDEC J-STD-609 markings. AEC-Q100 is not applicable for the standard -I grade; AEC-Q100-qualified variants exist in the automotive PIC18 K42 family but are separate orderable part numbers.
