PIC18F66K90-I/MR - 8-Bit XLP MCU 64KB Flash LCD | Microchip
MPN: PIC18F66K90-I/MR ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.62 | $5.62 |
| 10 | $5.07 | $50.70 |
| 100 | $4.51 | $451.00 |
| 500 | $4.05 | $2,025.00 |
| 1,000 | $3.62 | $3,620.00 |
PIC18F66K90-I/MR Overview
An 8-bit microcontroller (MCU) is a compact programmable processor that integrates CPU, Flash program memory, SRAM, peripherals, and I/O on a single silicon die. Within the hierarchy MCU -> microcontroller -> embedded processor -> semiconductor IC, the PIC18 family sits at the high-performance end of Microchip's 8-bit portfolio and targets low-power embedded designs requiring extended battery life, integrated analog, and human-interface features such as LCD and capacitive touch. The 'K90' series specifically adds an on-chip LCD segment driver and the Charge Time Measurement Unit (CTMU) for touch-key and capacitive measurement, eliminating external driver ICs and reducing BOM cost.
Key specifications include 64 KB Flash program memory organized as 32K x 16 words, 4 KB RAM, 1 KB EEPROM, an integrated 10-bit ADC, three analog comparators, two UART/USART modules, two SPI, two I2C, and a parallel port. The nanoWatt XLP technology enables sleep currents in the nanoamp range and Idle/Run currents suitable for battery-powered metering, wearable, and remote-sensor nodes. The 64-VQFN package exposes the thermal pad for low theta_JA, supporting operation across -40C to +85C industrial range. Programming is performed via ICSP or JTAG through the standard Microchip MPLAB X IDE and XC8 toolchain.
Typical applications include battery-powered utility metering with LCD readout, electronic shelf labels, home appliances with segment displays, medical glucose and infusion monitors, industrial control panels, and IoT sensor hubs with local touch input. The combination of LCD driver, CTMU touch sensing, and XLP low-power modes targets designs where bill-of-material count and quiescent current dominate the design constraint set. The 54 I/O lines also support keypad scanning, LED drive, and serial communication to host MCUs or radios.
When designing with this part, ensure the exposed pad is soldered to a sufficiently large copper pour to meet thermal and electrical grounding requirements. MPLAB X IDE plus the XC8 compiler provides full C-language support; the PIC18 instruction set is fully upward-compatible across the family, easing migration to PIC18F66K80 or PIC18F87K90 derivatives when more memory or I/O is required.
Drop-in alternatives for PIC18F66K90-I/MR — 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 PIC18F66K90-I/MR (same form factor and footprint) — differing in ADC, Package, Operating Temperature, Core Architecture, LCD Driver.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F65K90-I/MR
✅ Drop-In✓ In Stock
$3.02 / Unit
View Datasheet →PIC18F66K90-I/MRRSL
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F66K40-I/MR
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F66K22-I/MRRSL
✅ Drop-In✓ In Stock
$3.55 / Unit
View Datasheet →PIC18F87K90-I/MR
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F66J55-I/PT
✅ Drop-In✓ In Stock
$4.31 / Unit
View Datasheet →PIC18F66K90-I/MR Maximum Ratings & Electrical Characteristics
| Core | PIC18 8-bit RISC |
| Program Memory | 64 KB Flash (32K x 16) |
| RAM | 4 KB |
| EEPROM | 1 KB |
| Maximum CPU Frequency | 64 MHz |
| Supply Voltage Range | 1.8 V to 5.5 V |
| Digital I/O Pins | 54 |
| ADC | 10-bit, 12 channels |
| Comparators | 3 analog comparators |
| UART/USART | 2 |
| SPI | 2 |
| I2C (MSSP) | 2 |
| LCD Driver | On-chip segment LCD driver (up to 192 segments) |
| CTMU Module | Charge Time Measurement Unit (mTouch capacitive touch) |
| Operating Temperature | -40 C to +85 C (Industrial) |
| Package | 64-VQFN (9x9 mm) with exposed pad |
| Mounting Type | Surface Mount |
| MSL Level | 3 |
| RoHS Status | Compliant |
PIC18F66K90-I/MR Pin Configuration
| Pin 1 | RB7 — PORTB bit 7 / KBI3 / programming |
| Pin 2 | RB6 — PORTB bit 6 / KBI2 / programming clock |
| Pin 3 | RB5 — PORTB bit 5 / KBI1 |
| Pin 4 | RB4 — PORTB bit 4 / KBI0 |
| Pin 5 | VSS — Ground |
| Pin 6 | VDD — Positive supply |
| Pin 7 | RA7 — PORTA bit 7 |
| Pin 8 | RA6 — PORTA bit 6 |
| Pin 9 | RA5 — PORTA bit 5 |
| Pin 10 | RA4 — PORTA bit 4 |
| Pin 11 | RC7 — PORTC bit 7 / RX |
| Pin 12 | RC6 — PORTC bit 6 / TX |
| Pin 13 | RC5 — PORTC bit 5 |
| Pin 14 | RC4 — PORTC bit 4 |
| Pin 15 | RC3 — PORTC bit 3 / SCL |
| Pin 16 | RC2 — PORTC bit 2 / SDA |
| Pin 17 | RC1 — PORTC bit 1 / CCP |
| Pin 18 | RC0 — PORTC bit 0 |
| Pin 19 | OSC1 — Crystal oscillator input |
| Pin 20 | OSC2 — Crystal oscillator output |
| Pin 21 | VDD — Positive supply (secondary) |
| Pin 22 | VSS — Ground (secondary) |
| Pin 23 | RD7 — PORTD bit 7 |
| Pin 24 | RD6 — PORTD bit 6 |
| Pin 25 | RD5 — PORTD bit 5 |
| Pin 26 | RD4 — PORTD bit 4 |
| Pin 27 | RD3 — PORTD bit 3 |
| Pin 28 | RD2 — PORTD bit 2 |
| Pin 29 | RD1 — PORTD bit 1 |
| Pin 30 | RD0 — PORTD bit 0 |
| Pin 31 | RE7 — PORTE bit 7 |
| Pin 32 | RE6 — PORTE bit 6 |
| Pin 33 | RE5 — PORTE bit 5 |
| Pin 34 | RE4 — PORTE bit 4 |
| Pin 35 | RE3 — PORTE bit 3 / COM3 |
| Pin 36 | RE2 — PORTE bit 2 / COM2 |
| Pin 37 | RE1 — PORTE bit 1 / COM1 |
| Pin 38 | RE0 — PORTE bit 0 / COM0 |
| Pin 39 | RF7 — PORTF bit 7 / SEG7 |
| Pin 40 | RF6 — PORTF bit 6 / SEG6 |
| Pin 41 | RF5 — PORTF bit 5 / SEG5 |
| Pin 42 | RF4 — PORTF bit 4 / SEG4 |
| Pin 43 | RF3 — PORTF bit 3 / SEG3 |
| Pin 44 | RF2 — PORTF bit 2 / SEG2 |
| Pin 45 | RF1 — PORTF bit 1 / SEG1 |
| Pin 46 | RF0 — PORTF bit 0 / SEG0 |
| Pin 47 | RG7 — PORTG bit 7 |
| Pin 48 | RG6 — PORTG bit 6 |
| Pin 49 | RG5 — PORTG bit 5 |
| Pin 50 | RG4 — PORTG bit 4 |
| Pin 51 | RG3 — PORTG bit 3 |
| Pin 52 | RG2 — PORTG bit 2 |
| Pin 53 | RG1 — PORTG bit 1 |
| Pin 54 | RG0 — PORTG bit 0 |
| Pin 55 | AVSS — Analog ground |
| Pin 56 | AVDD — Analog positive supply |
| Pin 57 | MCLR — Master clear / reset / programming voltage |
| Pin 58 | RA3 — PORTA bit 3 |
| Pin 59 | RA2 — PORTA bit 2 |
| Pin 60 | RA1 — PORTA bit 1 |
| Pin 61 | RA0 — PORTA bit 0 |
| Pin 62 | VDD — Positive supply (tertiary) |
| Pin 63 | VSS — Ground (tertiary) |
| Pin 64 | RB3 — PORTB bit 3 / CCP |
Typical Applications
PIC18F66K90-I/MR is suitable for 6 applications: Battery-Powered Utility Metering with LCD, Electronic Shelf Labels (ESL), Home Appliance Control Panels, Medical Glucose and Infusion Monitors, Industrial Control Panels with Touch Interface, IoT Sensor Hubs with Local Display.
Battery-Powered Utility Metering with LCD
The PIC18F66K90-I/MR is purpose-built for battery-powered metering where an integrated LCD segment driver eliminates the external display controller IC. With nanoWatt XLP sleep currents under 100 nA and 1.8V minimum supply, the part operates from a single lithium thionyl-chloride cell for 10+ years. The 64 KB Flash holds metering firmware plus calibration tables, while the on-chip LCD driver directly drives 192 segments for kWh, voltage, and current readout, reducing BOM cost by $0.50-$1.00 per meter.
Recommended
Electronic Shelf Labels (ESL)
The PIC18F66K90-I/MR drives segmented or dot-matrix LCDs in retail electronic shelf labels with wireless update via UART/SPI to an attached sub-GHz radio. The 54 I/O pins support keypad scanning and LED status indication, while XLP deep-sleep modes enable multi-year coin-cell operation. The 4 KB RAM buffers pricing and product data between radio updates, and the CTMU module supports capacitive touch buttons on premium ESL models for staff override.
Recommended
Home Appliance Control Panels
In washing machines, dishwashers, ovens, and microwave ovens, the PIC18F66K90-I/MR drives segment LCDs showing time, temperature, and program status while scanning capacitive touch keys via CTMU. The 1.8V-5.5V supply works directly from rectified mains-derived rails, and the 64 KB Flash stores multilingual UI strings plus program logic. The 10-bit ADC reads temperature and humidity sensors for closed-loop control, with 54 I/O pins handling relays, triacs, and buzzer feedback.
Recommended
Medical Glucose and Infusion Monitors
The PIC18F66K90-I/MR suits portable medical devices such as blood glucose meters, infusion pumps, and patient monitors where low-power LCD readout and accurate analog measurement are required. The 10-bit ADC reads electrochemical test strips or pressure sensors, while the integrated LCD driver displays results without auxiliary ICs. nanoWatt XLP modes extend battery life across thousands of daily tests, and the 1.8V supply supports single-coin-cell operation with IEC 62304 firmware compliance.
Recommended
Industrial Control Panels with Touch Interface
Factory-floor HMI panels use the PIC18F66K90-I/MR to drive LCD status displays, scan capacitive touch keys via CTMU, and communicate with PLCs over UART, SPI, or RS-485. The 64 KB Flash stores multilingual fault diagnostics and machine state machines, while 54 I/O drive indicator LEDs, relay outputs, and buzzer alarms. The -40C to +85C industrial temperature rating and 5V tolerance suit uncontrolled cabinet environments, with the CTMU supporting gloved-finger touch detection.
Recommended
IoT Sensor Hubs with Local Display
IoT sensor hubs deployed in buildings or warehouses use the PIC18F66K90-I/MR to aggregate data from SPI/I2C sensors and present readings on a local segment LCD. The CTMU provides touch input for user setup and threshold adjustment, while XLP sleep modes enable battery or energy-harvested operation. The 54 I/O drive additional relays, actuators, and indicator LEDs, with the 64 KB Flash holding mesh-network firmware plus local decision logic.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F66K90-I/MR — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F65K90-I/MR | PIC18F66K40-I/MR | PIC18F66K22-I/MR | PIC18F87K90-I/MR |
|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 64-VQFN (9x9 mm) | 64-VQFN (9x9 mm) - same | 64-VQFN (9x9 mm) - same | 64-VQFN (9x9 mm) - same | 64-VQFN (9x9 mm) - same |
| Flash Memory | 64 KB | 32 KB | 64 KB | 64 KB | 128 KB |
| RAM | 4 KB | 2 KB | 4 KB | 4 KB | 4 KB |
| Maximum CPU Frequency | 64 MHz | 64 MHz | 64 MHz | 64 MHz | 64 MHz |
| Supply Voltage | 1.8 V to 5.5 V | 1.8 V to 5.5 V | 2.3 V to 5.5 V | 1.8 V to 5.5 V | 1.8 V to 5.5 V |
| Integrated LCD Driver | Yes (192 segments) | Yes | No | No | Yes (192 segments) |
| CTMU Touch Module | Yes | Yes | No (replaced by CWG) | No | Yes |
| Digital I/O Pins | 54 | 53 | 54 | 54 | 69 |
Key Differentiators
- Integrated segment LCD driver eliminates external controller (vs PIC18F66K22-I/MR)
- Higher Flash density for full-featured metering (vs PIC18F65K90-I/MR)
- Touch sensing via CTMU without dedicated IC (vs PIC18F66K40-I/MR)
Design Notes
Estimated: For a typical battery-powered meter running at 3V with the LCD active, average current draw at 1 MHz instruction rate is ~2 mA. In sleep mode with LCD off, XLP technology drops this below 100 nA, enabling 10+ year battery life from a single 2.4 Ah lithium cell. Ensure VDDCORE pin is properly decoupled with 10 uF + 100 nF per the datasheet reference circuit.
The 64-VQFN package exposes a thermal pad (pin 65) that MUST be soldered to a ground copper pour of at least 25 mm x 25 mm for proper thermal dissipation and electrical grounding. Daisy-chained ground vias in the thermal pad area improve thermal conductivity to internal planes. Per the Microchip package drawing, the pad also serves as the primary substrate connection.
When migrating from PIC18F66K22 to PIC18F66K90, note that the LCD segment pins on PORTE/PORTF are remapped - software configuration must be updated in the CONFIG registers. The CTMU peripheral requires calibration per device and the ADC channel assignments differ between K22 and K90 variants. Always re-validate timing-critical code after migration.
Compliance Information
RoHS compliant per Microchip product page. Industrial temperature grade -40C to +85C. Not AEC-Q100 qualified; automotive applications should use PIC18F66K80 or similar AEC-Q100 derivatives.
