PIC18LF66K40-E/PT - 8-bit 64KB Flash 64-Pin TQFP MCU | Microchip
MPN: PIC18LF66K40-E/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $3.85 | $3.85 |
| 10 | $3.55 | $35.50 |
| 100 | $3.1 | $310.00 |
| 500 | $2.75 | $1,375.00 |
| 1,000 | $2.4 | $2,400.00 |
PIC18LF66K40-E/PT Overview
A microcontroller (MCU) is a single-chip computer containing a CPU core, program memory (Flash), data memory (RAM), non-volatile EEPROM, and a range of peripheral interfaces. Within Microchip's hierarchy, the PIC18LF66K40 belongs to the PIC18 family -> PIC XLP -> 8-bit PIC microcontrollers -> microcontrollers -> integrated circuits -> semiconductors. The "LF" prefix indicates the low-voltage (1.8V-3.6V) process variant, complementing the higher-voltage "F" PIC18F66K40 (2.3V-5.5V) version of the same die.
Key differentiating features include: 64KB Flash program memory organized as 32K x 16, 4KB SRAM, 256B EEPROM, hardware CRC/SCAN memory checker, Windowed Watchdog Timer (WWDT), Complementary Waveform Generator (CWG), Zero-Cross Detect (ZCD), 10-bit ADC2 with Computation, 5-bit DAC, multiple communication peripherals (EUSART, SPI, I2C) with Peripheral Pin Select (PPS), and PWM/CCP/Capture-Compare modules. The XLP designation provides nanoWatt sleep currents below 50 nA typical in sleep mode.
Architecturally, the PIC18LF66K40 employs an enhanced RISC Harvard-bus core with a hardware multiplier, 31-level stack, and 16-bit instruction width. The "-E" suffix indicates the extended (-40C to +125C) operating temperature range for industrial and automotive under-hood applications, while "/PT" denotes the TQFP-64 (10x10 mm) package style with gull-wing leads suitable for surface-mount assembly.
Typical applications include IoT sensor nodes, low-power wireless modules, industrial control, automotive body electronics, home appliance control, battery-powered instrumentation, and consumer white goods. The 64-pin TQFP provides generous I/O count for richer peripheral allocation, and PPS allows flexible pin remapping.
Designers should consider that the LF variant cannot operate above 3.6V on VDD - if 5V rails are present in the system, level translation is required. The XLP low-power modes require careful peripheral gating to achieve the 50 nA sleep target, and programming/debug interfaces are available via ICSP (In-Circuit Serial Programming).
This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet alone.
Drop-in alternatives for PIC18LF66K40-E/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 PIC18LF66K40-E/PT (same form factor and footprint) — differing in Package, ADC, Mounting Type, Program Memory (Flash), RAM.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F66K40-E/PT
✅ Drop-In✓ In Stock
$2.78 / Unit
View Datasheet →PIC18LF66K40-I/PT
✅ Drop-In✓ In Stock
$3.85 / Unit
View Datasheet →PIC18LF65K40-E/PT
✅ Drop-In✓ In Stock
$2.85 / Unit
View Datasheet →PIC18LF46K40-E/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$1.05 / Unit
View Datasheet →PIC18LF56K42-E/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$2.15 / Unit
View Datasheet →PIC18LF66K40-E/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC 8-bit (PIC18) |
| Family | PIC XLP 18K |
| Core Size | 8-bit |
| CPU Speed (Max) | 64 MHz |
| Program Memory (Flash) | 64 KB (32K x 16) |
| RAM | 4 KB |
| EEPROM | 256 B |
| Operating Voltage (VDD) | 1.8 V to 3.6 V |
| Operating Temperature | -40 C to +125 C (E suffix - extended) |
| Package | 64-TQFP (10x10 mm) |
| Pin Count | 64 |
| I/O Pins | Approximately 60 |
| ADC | 10-bit ADC2 with Computation |
| DAC | 5-bit DAC |
| Communication | EUSART, SPI, I2C, PPS |
| PWM / CCP / CWG | Yes (PWM, CCP, Complementary Waveform Generator) |
| Watchdog | Windowed WDT (WWDT), Standard WDT |
| Special Peripherals | CWG, ZCD, SCAN/CRC, HLT, PPS, ECCP |
| Low-Power Technology | XLP nanoWatt (sleep <50 nA typical) |
| Programming | ICSP (In-Circuit Serial Programming) |
| Mounting Type | Surface Mount (gull-wing leads) |
| MSL Level | 3 (per JEDEC J-STD-020, generic for TQFP-64) |
| RoHS Status | Compliant |
| Series | PIC18(L)F6xK40 |
PIC18LF66K40-E/PT Pin Configuration
| Pin 1 | RC0 — Digital I/O / analog input |
| Pin 2 | RC1 — Digital I/O / analog input |
| Pin 3 | RC2 — Digital I/O / analog input |
| Pin 4 | RC3 — Digital I/O / analog input |
| Pin 5 | RC4 — Digital I/O / analog input |
| Pin 6 | RC5 — Digital I/O / analog input |
| Pin 7 | RC6 — Digital I/O / TX (EUSART) |
| Pin 8 | RC7 — Digital I/O / RX (EUSART) |
| Pin 9 | RE0 — Digital I/O |
| Pin 10 | RE1 — Digital I/O |
| Pin 11 | RE2 — Digital I/O |
| Pin 12 | RE3 — Digital I/O |
| Pin 13 | VDD — Positive supply voltage |
| Pin 14 | VSS — Ground reference |
| Pin 15 | RA0 — Digital I/O / analog input |
| Pin 16 | RA1 — Digital I/O / analog input |
| Pin 17 | RA2 — Digital I/O / analog input |
| Pin 18 | RA3 — Digital I/O / analog input |
| Pin 19 | RA4 — Digital I/O |
| Pin 20 | RA5 — Digital I/O |
| Pin 21 | RA6 — Digital I/O |
| Pin 22 | RA7 — Digital I/O |
| Pin 23 | VSS — Ground reference |
| Pin 24 | VDD — Positive supply voltage |
| Pin 25 | RB0 — Digital I/O / analog input / interrupt |
| Pin 26 | RB1 — Digital I/O / analog input |
| Pin 27 | RB2 — Digital I/O / analog input |
| Pin 28 | RB3 — Digital I/O / analog input |
| Pin 29 | RB4 — Digital I/O / analog input |
| Pin 30 | RB5 — Digital I/O / analog input |
| Pin 31 | RB6 — Digital I/O / ICSP clock |
| Pin 32 | RB7 — Digital I/O / ICSP data |
| Pin 33 | VDDCORE — Regulated core supply decoupling |
| Pin 34 | VSS — Ground reference |
| Pin 35 | RD0 — Digital I/O / analog input |
| Pin 36 | RD1 — Digital I/O / analog input |
| Pin 37 | RD2 — Digital I/O / analog input |
| Pin 38 | RD3 — Digital I/O / analog input |
| Pin 39 | RD4 — Digital I/O / analog input |
| Pin 40 | RD5 — Digital I/O / analog input |
| Pin 41 | RD6 — Digital I/O / analog input |
| Pin 42 | RD7 — Digital I/O / analog input |
| Pin 43 | VSS — Ground reference |
| Pin 44 | VDD — Positive supply voltage |
| Pin 45 | RF0 — Digital I/O / analog input |
| Pin 46 | RF1 — Digital I/O / analog input |
| Pin 47 | RF2 — Digital I/O / analog input |
| Pin 48 | RF3 — Digital I/O / analog input |
| Pin 49 | RF4 — Digital I/O / analog input |
| Pin 50 | RF5 — Digital I/O / analog input |
| Pin 51 | RF6 — Digital I/O / analog input |
| Pin 52 | RF7 — Digital I/O / analog input |
| Pin 53 | RG0 — Digital I/O |
| Pin 54 | RG1 — Digital I/O |
| Pin 55 | RG2 — Digital I/O |
| Pin 56 | RG3 — Digital I/O |
| Pin 57 | RG4 — Digital I/O |
| Pin 58 | OSC1 — Crystal oscillator input / external clock |
| Pin 59 | OSC2 — Crystal oscillator output |
| Pin 60 | VDD — Positive supply voltage |
| Pin 61 | VSS — Ground reference |
| Pin 62 | MCLR — Master clear reset (active low) |
| Pin 63 | RA0 — Digital I/O / analog input (alternate) |
| Pin 64 | RA1 — Digital I/O / analog input (alternate) |
Typical Applications
PIC18LF66K40-E/PT is suitable for 6 applications: IoT Sensor Nodes, Industrial Control & Automation, Automotive Body Electronics, Battery-Powered Instrumentation, Home Appliance Control, Low-Power Wireless Modules.
IoT Sensor Nodes
The PIC18LF66K40-E/PT fits IoT sensor nodes due to its XLP nanoWatt technology delivering sleep currents below 50 nA and its 1.8V-3.6V VDD range that aligns directly with Li-ion/coin-cell chemistries. The 64KB Flash holds application code plus a wireless stack shim for protocols like LoRa, Sigfox, or BLE-HID bridging, while 4KB RAM supports RTOS-lite or state-machine firmware. The integrated 10-bit ADC2 with Computation offloads sensor linearization in hardware, freeing the core for power-management tasks. Used between the battery and a sub-GHz transceiver, the MCU's low quiescent current extends multi-year battery life.
Recommended
Industrial Control & Automation
The PIC18LF66K40-E/PT is well-matched to industrial control tasks thanks to its -40C to +125C extended operating range, Windowed Watchdog Timer (WWDT), and hardware CRC/SCAN memory checker for functional safety in PLCs, motor controllers, and sensor interfaces. The Complementary Waveform Generator (CWG) and ECCP module drive half-bridge power stages for small DC motors and solenoids without external logic. PPS pin remapping simplifies PCB routing when assigning PWM, ADC, and comm signals across the 60+ I/O pins. The 64-pin TQFP-64 (10x10 mm) provides generous I/O for multi-axis control while keeping the board compact.
Recommended
Automotive Body Electronics
The PIC18LF66K40-E/PT suits automotive body controllers including HVAC blend doors, seat controls, mirror adjusters, and lighting modules, where the extended -40C to +125C thermal range handles under-hood and cabin extremes. The hardware Windowed Watchdog and CRC/SCAN features help meet OEM functional-safety requirements, while the EUSART/SPI/I2C set interfaces with body-domain LIN transceivers and sensor clusters. LF variant operates from a single 3.3V LDO downstream of the 12V battery. For AEC-Q100 certified applications, designers should evaluate Microchip's separate automotive-qualified part numbers rather than the standard E-grade catalog part.
Recommended
Battery-Powered Instrumentation
The PIC18LF66K40-E/PT excels in handheld meters, medical portables, and field instrumentation where the XLP low-power architecture and 1.8V VDD minimum extend battery life across coin-cell, Li-Po, or 2xAA chemistries. The integrated 5-bit DAC and 10-bit ADC2 with computation provide the analog front end for sensor excitation, signal conditioning, and threshold detection without external op-amps. With 64KB Flash, designers can embed calibration tables, custom units, and graphical LCD driving code, reducing BOM cost. PPS flexibility simplifies mixed-signal PCB layouts when routing the LCD segment driver alongside ADC inputs.
Recommended
Home Appliance Control
The PIC18LF66K40-E/PT integrates well into white-goods controllers such as washing machines, dishwashers, ovens, and refrigerators, where its extended temperature range and motor-control peripherals provide the analog and digital I/O needed for brushed-DC and universal-motor drive stages. The 64-pin TQFP-64 (10x10 mm) is large enough for HMI matrix keypads, seven-segment displays, and triac-fired heater elements while keeping the board compact. The hardware CRC/SCAN adds diagnostic capability for compliance with household appliance safety standards. The LF variant draws minimal standby power to meet Energy Star idle-draw limits.
Recommended
Low-Power Wireless Modules
The PIC18LF66K40-E/PT pairs naturally with sub-GHz RF transceivers (e.g., Microchip MRF89XA) or BLE modules for end-node wireless products including smart meters, asset trackers, and remote sensor bridges. XLP sleep below 50 nA keeps idle current negligible while the radio sleeps; the 64MHz core wakes quickly to handle over-the-air protocols and AES-style packet processing. The 4KB SRAM supports buffering of inbound packets during brief RX windows. PPS allows remapping SPI signals to optimize RF PCB layout for controlled-impedance antenna feed traces.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF66K40-E/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F66K40-E/PT | PIC18LF66K40-I/PT | PIC18LF65K40-E/PT | PIC18LF46K40-E/PT | PIC18LF56K42-E/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-TQFP (10x10 mm) | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same | 64-TQFP (10x10 mm) - same |
| Flash Memory | 64 KB | 64 KB | 64 KB | 32 KB | 16 KB | 64 KB |
| RAM | 4 KB | 4 KB | 4 KB | 2 KB | 1 KB | 4 KB |
| Operating Voltage (VDD) | 1.8V to 3.6V (LF) | 2.3V to 5.5V (F) | 1.8V to 3.6V (LF) | 1.8V to 3.6V (LF) | 1.8V to 3.6V (LF) | 1.8V to 3.6V (LF) |
| Operating Temperature | -40C to +125C (E grade) | -40C to +125C (E) | -40C to +85C (I) | -40C to +125C (E) | -40C to +125C (E) | -40C to +125C (E) |
| CPU Speed (Max) | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| EEPROM | 256 B | 256 B | 256 B | 256 B | 256 B | 256 B |
| Generation / Family | PIC18F66K40 (K40 series) | PIC18F66K40 (K40) | PIC18LF66K40 (K40) | PIC18LF65K40 (K40) | PIC18LF46K40 (K40) | PIC18LF56K42 (K42, newer) |
| XLP Low-Power Sleep | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (<50 nA typical) | Yes (K42 enhanced XLP) |
Key Differentiators
- Wider 1.8V-3.6V operating range vs F-variant (vs PIC18F66K40-E/PT)
- Extended -40C to +125C temperature range (vs PIC18LF66K40-I/PT)
- Doubled Flash and RAM vs 65K40 sibling (vs PIC18LF65K40-E/PT)
- 64KB Flash matches newer K42 generation (vs PIC18LF56K42-E/PT)
Design Notes
The LF variant operates from 1.8V to 3.6V VDD; do not exceed 3.6V. Place a 100nF decoupling capacitor as close as possible to each VDD pin pair (the TQFP-64 has 3 VDD pins and 3 VSS pins routed to multiple supply pads). For battery applications, add a 10uF bulk capacitor near the VDD pins to handle transient loads when the radio or sensor wakes. Use the LF process if your rail is 3.3V or below; switch to the F variant (PIC18F66K40-E/PT) only if your system requires 5V tolerance.
The 64-TQFP (10x10 mm) package has 0.5mm pitch gull-wing leads - design the PCB land pattern per JEDEC MS-026-AED with 0.27mm lead-width pads and ~1.5mm to 2.0mm lead length for reliable reflow soldering. Allow at least 8mm of clearance beyond the package outline for probe access during debug. Use a continuous ground pour under the device to provide thermal spreading and EMI shielding; stitch the VDD/GND pours with multiple vias adjacent to each supply pin. Keep the ICSP clock/data traces (RB6/RB7) short and free of nearby switching signals.
Do not substitute PIC18LF66K40-I/PT (-40C to +85C, industrial) for the -E grade (-40C to +125C, extended) in automotive/under-hood designs - the -I grade fails to meet the upper temperature limit. Always verify the suffix letter against Microchip's ordering nomenclature. The MCLR pin (pin 62) requires a 10k pull-up to VDD and a 100nF cap to ground for proper reset behavior; omitting the cap allows noise to false-trigger resets. When migrating code from PIC18F46K22 or PIC18F26K22, reconfigure PPS registers for the new peripheral pin mapping - PPS defaults differ across PIC18 generations.
The PIC18LF66K40-E/PT supports Peripheral Pin Select (PPS), which remaps digital peripherals to most I/O pins. While PPS dramatically simplifies PCB routing, it adds 1-2 ns of propagation delay through the internal mux; for high-speed SPI or EUSART at 64MHz FOSC, prefer using the default peripheral pin assignments to avoid signal degradation. The 10-bit ADC2 input impedance is moderate - if driving from a high-impedance source (>10 kohm), buffer the signal with an op-amp to avoid ADC conversion errors. Use PPS to keep analog inputs physically separated from PWM outputs to reduce digital switching noise coupling into ADC measurements.
Compliance Information
RoHS compliant per Microchip product page. E suffix indicates extended temperature but not AEC-Q100 automotive qualification; for AEC-Q100 certified parts refer to Microchip's automotive product catalog. Lead-free and halogen-free per Microchip environmental compliance disclosures.
