PIC18LF8490-I/PT - 8-bit MCU 16KB Flash 768 RAM 66 I/O | Microchip
MPN: PIC18LF8490-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $8.42 | $8.42 |
| 10 | $7.59 | $75.90 |
| 100 | $6.41 | $641.00 |
| 500 | $5.82 | $2,910.00 |
| 1,000 | $5.18 | $5,180.00 |
PIC18LF8490-I/PT Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, non-volatile program memory, working RAM, and programmable peripherals into one device. The PIC18 family adds RISC Harvard architecture, hardware multiplier, and 16-bit instruction width to the classic 8-bit PIC core, raising throughput to 10 MIPS while preserving the PIC instruction-set familiarity that millions of embedded engineers already know. MCUs of this class sit one tier above discrete logic and one tier below microprocessors, anchoring everything from consumer appliances to industrial control boards.
Key features include 66 digital I/O pins, 12 channels of 10-bit ADC, two analog comparators, two USART modules, an MSSP module that supports SPI and I2C (master and slave), two CCP modules plus one enhanced ECCP for PWM and capture, a 16-bit timer/counter, three 8-bit timers, and a 10-bit addressable Enhanced USART. A 4x phase-locked loop, internal 31 kHz oscillator, and low-power SLEEP/IDLE modes round out the peripheral set.
Typical applications include industrial control panels, white goods and HVAC controls, USB/HID bridges using the on-chip transceiver-less USART, sensor hubs, motor-control BLDC/PMSM drivers when paired with the ECCP PWM, medical handhelds, and battery-powered instrumentation that benefits from the 2.0 V minimum supply. The wide 2.0 V to 5.5 V range also supports solar and energy-harvesting designs.
Designers should note that the LF variant uses the lower Fmax at low VDD and that 80-pin TQFP routing benefits from a 4-layer PCB with a continuous ground pour under the part. In-system programming via ICSP requires dedicated RB6/ICSP-CLK and RB7/ICSP-DAT lines that must not be pulled low at reset.
This page consolidates distributor pricing, verified pin-compatible drop-in alternatives, and practical engineering notes that go beyond the manufacturer datasheet to speed up your design-in.
Drop-in alternatives for PIC18LF8490-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 PIC18LF8490-I/PT (same form factor and footprint) — differing in Package, ADC, Program Memory, Core Architecture, Maximum CPU Speed.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F8490-I/PT
✅ Drop-In✓ In Stock
$5.55 / Unit
View Datasheet →PIC18LF8393-I/PT
✅ Drop-In✓ In Stock
$4.96 / Unit
View Datasheet →PIC18LF8390-I/PT
✅ Drop-In✓ In Stock
$2.1 / Unit
View Datasheet →PIC18LF8490-I/PT Maximum Ratings & Electrical Characteristics
| Architecture | 8-bit PIC18 RISC |
| Program Memory | 16 KB Flash |
| RAM | 768 bytes |
| EEPROM | 256 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Supply Voltage (VDD) | 2.0 V to 5.5 V |
| I/O Pins | 66 |
| ADC | 12 channels x 10-bit |
| Package | 80-pin TQFP (PT) |
| Operating Temperature | -40C to +85C (Industrial, "I") |
| Timers | 1 x 16-bit, 3 x 8-bit |
| PWM / CCP | 2 CCP + 1 ECCP |
| Communication | 2x USART, MSSP (SPI / I2C) |
| Comparators | 2 analog comparators |
| Internal Oscillator | 31 kHz LFINTOSC + 8 MHz HFINTOSC |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant |
| MSL Level | 3 (168 hours) |
PIC18LF8490-I/PT Pin Configuration
| Pin 1 | RA0/AN0 — PORTA bit 0 / Analog input 0 |
| Pin 2 | RA1/AN1 — PORTA bit 1 / Analog input 1 |
| Pin 3 | RA2/AN2 — PORTA bit 2 / Analog input 2 |
| Pin 4 | RA3/AN3/VREF+ — PORTA bit 3 / Analog input 3 / ADC VREF+ |
| Pin 5 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 6 | RA5/AN4/SS — PORTA bit 5 / Analog input 4 / SPI slave select |
| Pin 7 | RA6 — PORTA bit 6 |
| Pin 8 | RA7 — PORTA bit 7 |
| Pin 9 | RE0/RD — PORTE bit 0 / Parallel-port read control |
| Pin 10 | RE1/WR — PORTE bit 1 / Parallel-port write control |
| Pin 11 | RE2/CS — PORTE bit 2 / Parallel-port chip select |
| Pin 12 | VDD — Digital supply voltage (2.0-5.5 V) |
| Pin 13 | VSS — Digital ground |
| Pin 14 | OSC1/CLKI/RA7 — Crystal oscillator input / external clock |
| Pin 15 | OSC2/CLKO/RA6 — Crystal oscillator output / clock out |
| Pin 16 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / T1 clock |
| Pin 17 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 18 | RC2/CCP1 — PORTC bit 2 / CCP1 PWM output |
| Pin 19 | RC3/SCK/SCL — PORTC bit 3 / SPI SCK / I2C SCL |
| Pin 20 | RD0/PSP0 — PORTD bit 0 / Parallel slave port data 0 |
| Pin 21 | RD1/PSP1 — PORTD bit 1 / Parallel slave port data 1 |
| Pin 22 | RD2/PSP2 — PORTD bit 2 / Parallel slave port data 2 |
| Pin 23 | RD3/PSP3 — PORTD bit 3 / Parallel slave port data 3 |
| Pin 24 | RC4/SDI/SDA — PORTC bit 4 / SPI SDI / I2C SDA |
| Pin 25 | RC5/SDO — PORTC bit 5 / SPI SDO |
| Pin 26 | RC6/TX/CK — PORTC bit 6 / USART TX / USART clock |
| Pin 27 | RC7/RX/DT — PORTC bit 7 / USART RX / USART data |
| Pin 28 | RD4/PSP4 — PORTD bit 4 / Parallel slave port data 4 |
| Pin 29 | RD5/PSP5 — PORTD bit 5 / Parallel slave port data 5 |
| Pin 30 | RD6/PSP6 — PORTD bit 6 / Parallel slave port data 6 |
| Pin 31 | RD7/PSP7 — PORTD bit 7 / Parallel slave port data 7 |
| Pin 32 | VSS — Digital ground |
| Pin 33 | VDD — Digital supply voltage |
| Pin 34 | RB0/INT0 — PORTB bit 0 / External interrupt 0 |
| Pin 35 | RB1/INT1 — PORTB bit 1 / External interrupt 1 |
| Pin 36 | RB2/INT2 — PORTB bit 2 / External interrupt 2 |
| Pin 37 | RB3/INT3/ECCP — PORTB bit 3 / External interrupt 3 / ECCP |
| Pin 38 | RB4 — PORTB bit 4 |
| Pin 39 | RB5 — PORTB bit 5 |
| Pin 40 | RB6/ICSPCLK — PORTB bit 6 / ICSP clock |
| Pin 41 | RB7/ICSPDAT — PORTB bit 7 / ICSP data |
| Pin 42 | AVDD — Analog supply voltage |
| Pin 43 | AVSS — Analog ground |
| Pin 44 | RF0/AN5 — PORTF bit 0 / Analog input 5 |
| Pin 45 | RF1/AN6 — PORTF bit 1 / Analog input 6 |
| Pin 46 | RF2/AN7 — PORTF bit 2 / Analog input 7 |
| Pin 47 | RF3/AN8 — PORTF bit 3 / Analog input 8 |
| Pin 48 | RF4/AN9 — PORTF bit 4 / Analog input 9 |
| Pin 49 | RF5/AN10/CVREF — PORTF bit 5 / Analog input 10 / comparator VREF |
| Pin 50 | RF6/AN11 — PORTF bit 6 / Analog input 11 |
| Pin 51 | RF7 — PORTF bit 7 |
| Pin 52 | RG0 — PORTG bit 0 |
| Pin 53 | RG1 — PORTG bit 1 |
| Pin 54 | RG2 — PORTG bit 2 |
| Pin 55 | RG3 — PORTG bit 3 |
| Pin 56 | RG4 — PORTG bit 4 |
| Pin 57 | MCLR/VPP — Master clear reset / programming voltage |
| Pin 58 | RG5 — PORTG bit 5 |
| Pin 59 | RG6 — PORTG bit 6 |
| Pin 60 | RG7 — PORTG bit 7 |
| Pin 61 | RH0 — PORTH bit 0 |
| Pin 62 | RH1 — PORTH bit 1 |
| Pin 63 | RH2 — PORTH bit 2 |
| Pin 64 | RH3 — PORTH bit 3 |
| Pin 65 | RH4 — PORTH bit 4 |
| Pin 66 | RH5 — PORTH bit 5 |
| Pin 67 | RH6 — PORTH bit 6 |
| Pin 68 | RH7 — PORTH bit 7 |
| Pin 69 | RJ0 — PORTJ bit 0 |
| Pin 70 | RJ1 — PORTJ bit 1 |
| Pin 71 | RJ2 — PORTJ bit 2 |
| Pin 72 | RJ3 — PORTJ bit 3 |
| Pin 73 | RJ4 — PORTJ bit 4 |
| Pin 74 | RJ5 — PORTJ bit 5 |
| Pin 75 | RJ6 — PORTJ bit 6 |
| Pin 76 | RJ7 — PORTJ bit 7 |
| Pin 77 | RK0 — PORTK bit 0 |
| Pin 78 | RK1 — PORTK bit 1 |
| Pin 79 | RK2 — PORTK bit 2 |
| Pin 80 | RK3 — PORTK bit 3 |
Typical Applications
PIC18LF8490-I/PT is suitable for 6 applications: Industrial Control Panels, HVAC and White Goods Control, Battery-Powered Sensor Hubs, USB HID Bridges (Serial-to-USB), Motor Control (BLDC / PMSM), Medical Handheld Instrumentation.
Industrial Control Panels
The PIC18LF8490-I/PT fits industrial control panels because its 66 I/O pins directly drive key-matrix keypads, LED or LCD status indicators, relay coils, and opto-isolated digital inputs without external mux ICs. The wide 2.0-5.5 V VDD tolerates loosely regulated 24 V-to-5 V industrial rails that sag during inrush, while the -40C to +85C industrial temperature rating survives cabinet and outdoor-enclosure environments. The 12-channel 10-bit ADC reads potentiometers, panel-meter shunts, and 4-20 mA loop sensors with 4 mV resolution at 5 V full-scale. The 2 USARTs plus MSSP allow simultaneous RS-485 Modbus and SPI sensor expansion, and 10 MIPS CPU throughput handles local PID loops faster than typical 1 ms control periods.
Recommended
HVAC and White Goods Control
HVAC and white-goods controllers benefit from the PIC18LF8490-I/PT's wide 2.0-5.5 V supply, which accepts both 3.3 V logic from modern Wi-Fi/BLE modules and 5 V relay-driver rails in the same design. The 2 CCP + 1 ECCP block delivers hardware PWM for triac-firing of compressor valves, fan speed control, and variable-frequency pump drives, offloading the CPU so a single core can supervise the full appliance. The 16 KB flash comfortably holds user-interface state machines plus lookup tables for sensor linearization. Built-in analog comparators provide brown-out detection and zero-crossing for line-voltage synchronization, reducing external component count. The 1,000-cycle flash endurance is well-matched to firmware-update-tolerant consumer lifecycles of seven to ten years.
Recommended
Battery-Powered Sensor Hubs
Battery-powered sensor hubs are an ideal application for the PIC18LF8490-I/PT because the LF prefix guarantees operation down to 2.0 V, which is critical when running from a single Li-ion cell near end-of-discharge or from 2xAA alkalines that sag below 2.4 V. The internal 31 kHz LFINTOSC plus low-power SLEEP and IDLE modes let the core idle at microamp currents between sensor reads, while the MSSP wakes the PIC to read SPI or I2C sensors on demand. The 12-channel ADC reads battery voltage, current shunt, and multiple analog sensors without external muxes, and the 16 KB flash stores calibration tables for temperature-compensated measurements. Solar and energy-harvesting designs benefit from the same wide-Vin range.
Recommended
USB HID Bridges (Serial-to-USB)
The PIC18LF8490-I/PT is widely used in legacy serial-to-USB HID bridges where an external USB transceiver such as the MCP2200 or MCP2221A provides the USB Physical layer and the PIC handles the application side. The wide 2.0-5.5 V supply matches the 3.3 V USB-transceiver rail and 5 V VBUS-powered targets alike, and the 2 USARTs bridge to RS-232 or RS-485 endpoints. The 16 KB flash and 768 B RAM are sufficient for command parsers, vendor-report formatting, and EEPROM-backed configuration storage. Industrial-grade -40C to +85C operation survives factory-floor chassis, and ICSP via RB6/RB7 allows field firmware updates through a 6-pin header.
Recommended
Motor Control (BLDC / PMSM)
BLDC and PMSM motor-control applications pair naturally with the PIC18LF8490-I/PT because the enhanced ECCP module provides center-aligned PWM with dead-band control and hardware fault shutdown - features essential for three-phase inverter drives. The 12-channel 10-bit ADC samples phase currents and back-EMF at up to 500 ksps, while the 16 KB flash holds six-step or sinusoidal commutation tables. The 80-pin TQFP exposes enough I/O for Hall sensors, encoder inputs, brake, and fault lines without multiplexing. The wide 2.0-5.5 V range simplifies start-up from 24 V or 48 V battery packs stepped down to logic rails, and the industrial temperature rating supports outdoor power-tool and e-bike environments.
Recommended
Medical Handheld Instrumentation
Medical handhelds such as spot-check pulse oximeters, glucose meters, and digital thermometers are well served by the PIC18LF8490-I/PT thanks to its low-voltage operation, industrial temperature range, and deterministic interrupt latency under 200 ns. The 12-channel ADC reads optical sensor photodiodes and thermistor bridges with predictable acquisition timing, and the 16 KB flash holds lookup tables for SpO2 calibration and unit-of-measure conversions. The LF variant's 2.0 V minimum extends runtime on coin-cell and Li-Po batteries, while the 2 analog comparators provide hardware battery-low and signal-clipping detection without CPU intervention. Medical-grade designs can pair this MCU with external IEC 60601-isolated ADCs for higher resolution.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF8490-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F8490-I/PT | PIC18LF8393-I/PT | PIC18LF8390-I/PT |
|---|---|---|---|---|
| Package | 80-pin TQFP (PT) | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same | 80-pin TQFP (PT) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory | 16 KB Flash | 16 KB Flash | 8 KB Flash | 8 KB Flash |
| RAM | 768 bytes | 768 bytes | 336 bytes | 336 bytes |
| Supply Voltage | 2.0 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V | 2.0 V to 5.5 V |
| I/O Pins | 66 | 66 | 66 | 66 |
| ADC Channels | 12 x 10-bit | 12 x 10-bit | 12 x 10-bit | 12 x 10-bit |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Wide-voltage 2.0-5.5 V supply range (vs PIC18F8490-I/PT)
- Larger 16 KB flash and 768 B RAM in the same 80-pin TQFP (vs PIC18LF8393-I/PT)
- Industrial -40C to +85C temperature grade (vs PIC18F8490-I/PT (also industrial))
Design Notes
The PIC18LF8490-I/PT has separate AVDD/AVSS and VDD/VSS pairs. Tie both VDD pins together and both VSS pins together at the IC, and decouple each pair with a 100 nF ceramic plus 10 uF bulk within 5 mm of the pin. The AVDD pin should be filtered with a small ferrite bead or 10 ohm resistor and a 100 nF cap to its own quiet ground (AVSS). This prevents digital switching noise on VDD from coupling into the ADC reference and degrading 10-bit conversions by 1-2 LSBs.
The 80-pin TQFP body is 12x12 mm with a 0.5 mm pitch and an exposed thermal pad (E-pad) that must be soldered to a continuous ground pour for mechanical reliability. A 4-layer PCB with a dedicated ground plane directly under the part is recommended; route high-speed signals (USART, SPI, PWM) on the top layer with a continuous ground reference on layer 2. Keep crystal traces within 5 mm of OSC1/OSC2, shield them with a guard trace tied to ground, and place the load capacitors within 2 mm of the OSC pins to minimize stray capacitance.
Three common pitfalls: (1) Do not pull RB6/ICSPCLK or RB7/ICSPDAT low at reset, or the device will refuse to enter ICSP mode - add 10 kohm pull-ups if the application drives these pins low. (2) Do not exceed 5.5 V on any pin, including MCLR/VPP; if you apply 12 V for high-voltage programming, ensure no other pin sees more than 5.5 V. (3) The LF variant does not support the higher 40 MHz FOSC at VDD below 4.2 V - confirm your minimum supply voltage before specifying full-speed operation in battery-powered designs.
Compliance Information
RoHS and REACH compliant per Microchip product page. The I-suffix denotes industrial -40C to +85C grade, not AEC-Q100 automotive; for AEC-Q100 look at E or Q-suffixed PIC18LF variants.
