PIC18LF8585-I/PT - 8-bit 40MHz MCU 48KB Flash 80-TQFP | Microchip
MPN: PIC18LF8585-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $9.13 | $9.13 |
| 10 | $8.45 | $84.50 |
| 100 | $7.65 | $765.00 |
| 500 | $6.95 | $3,475.00 |
| 1,000 | $6.2 | $6,200.00 |
PIC18LF8585-I/PT Overview
A microcontroller (MCU) is a single-chip computer that integrates a CPU core, program and data memory, peripherals, and I/O on one die. PIC18F-series parts use Microchip's enhanced 8-bit Harvard RISC architecture with a 16-bit instruction word, providing single-cycle execution and a rich peripheral set (ADC, CCP, USART, I2C, SPI) optimized for embedded control. They sit in the taxonomy: microcontroller -> embedded processor -> semiconductor -> integrated circuit.
Key features of the PIC18LF8585-I/PT include 48 KB (24K x 16) self-programmable Flash with EEPROM emulation, 3328 bytes of RAM, a 10-bit ADC with up to 16 channels, two Capture/Compare/PWM modules, dual USART ports, MSSP (SPI/I2C), and CAN-ready peripherals typical of the PIC18F8585 silicon. The LF variant (LF = low-voltage Flash) extends operating flexibility down to ~2 V core while the I/PT suffix specifies the industrial temperature grade and TQFP-80 package.
Architecturally, the device uses a 16-bit program bus and 8-bit data bus with hardware multiply, a 32-level hardware stack, and prioritized interrupts. The wide 80-pin footprint is needed because the PIC18F8585 silicon integrates a large number of analog and digital peripherals aimed at industrial and automotive subsystem designs where code compatibility with the smaller-pin PIC18 family matters.
Typical applications include industrial automation controllers, HVAC and appliance control, automotive body and instrument clusters, sensor conditioning nodes, and general-purpose embedded products requiring high I/O count with Flash reprogrammability. The combination of CAN peripherals and 68 I/O makes it a common choice in mid-2000s automotive ECUs.
When designing with this part, plan for an external resonator or crystal (HS/EC mode) for accurate 40 MHz operation, ensure adequate decoupling (0.1 uF + bulk) per VDD/VSS pair, and review the ICSP/ICD pin assignments on the 80-TQFP layout so they remain accessible for in-circuit debug. Designers migrating from smaller PIC18 parts (e.g., PIC18F452) gain more I/O, CAN, and ADC channels but must re-route the PCB.
This page synthesizes distributor pricing, drop-in same-package alternatives drawn from the Microchip PIC18F/LF family, and practical design notes not consolidated in the manufacturer datasheet.
Drop-in alternatives for PIC18LF8585-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 PIC18LF8585-I/PT (same form factor and footprint) — differing in Package, I/O Pins, Operating Temperature, Core Architecture, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F8585-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF8585T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF6680T-I/PT
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC18LF8525-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$5.48 / Unit
View Datasheet →PIC18LF8527T-I/PT
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$4.65 / Unit
View Datasheet →PIC18LF8585-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC, Harvard) |
| Program Memory (Flash) | 48 KB (24K x 16) |
| RAM | 3328 bytes |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Operating Voltage (VDD) | 4.2 V to 5.5 V |
| I/O Pins | 68 |
| Package | 80-pin TQFP (PT), 12x12 mm, 0.5 mm pitch |
| Operating Temperature | -40 C to +85 C (Industrial) |
| ADC | 10-bit, multi-channel |
| CCP/ECCP Modules | Yes |
| USART | Yes (2x) |
| MSSP (SPI / I2C) | Yes |
| CAN | Peripheral present on PIC18F8585 silicon |
| Timers | Multiple 8/16-bit |
| Mounting Type | Surface Mount |
| Lead-Free / RoHS | Yes (LEAD FREE per package code) |
| MSL Level | 3 (per TQFP-80 handling) |
| Lifecycle Stage | ACTIVE |
PIC18LF8585-I/PT Pin Configuration
| Pin 1 | RG0 — Port G bit 0 / CCP3 / TX2 |
| Pin 2 | RG1 — Port G bit 1 / RX2 |
| Pin 3 | RG2 — Port G bit 2 |
| Pin 4 | RG3 — Port G bit 3 |
| Pin 5 | RG4 — Port G bit 4 |
| Pin 6 | AVSS — Analog ground |
| Pin 7 | AVDD — Analog supply |
| Pin 8 | RH0 — Port H bit 0 / analog input |
| Pin 9 | RH1 — Port H bit 1 / analog input |
| Pin 10 | RH2 — Port H bit 2 / analog input |
| Pin 11 | RH3 — Port H bit 3 / analog input |
| Pin 12 | RH4 — Port H bit 4 |
| Pin 13 | RH5 — Port H bit 5 |
| Pin 14 | RH6 — Port H bit 6 |
| Pin 15 | RH7 — Port H bit 7 |
| Pin 16 | VSS — Digital ground |
| Pin 17 | VDD — Digital supply |
| Pin 18 | OSC1 — Oscillator input |
| Pin 19 | OSC2 — Oscillator output |
| Pin 20 | RA0 — Port A bit 0 / analog input |
| Pin 21 | RA1 — Port A bit 1 / analog input |
| Pin 22 | RA2 — Port A bit 2 / analog input |
| Pin 23 | RA3 — Port A bit 3 / analog input / VREF+ |
| Pin 24 | RA4 — Port A bit 4 |
| Pin 25 | RA5 — Port A bit 5 |
| Pin 26 | RA6 — Port A bit 6 / OSC1 |
| Pin 27 | RA7 — Port A bit 7 / OSC2 |
| Pin 28 | VSS — Digital ground |
| Pin 29 | VDD — Digital supply |
| Pin 30 | RB0 — Port B bit 0 / INT0 |
| Pin 31 | RB1 — Port B bit 1 / INT1 |
| Pin 32 | RB2 — Port B bit 2 / INT2 |
| Pin 33 | RB3 — Port B bit 3 / INT3 |
| Pin 34 | RB4 — Port B bit 4 |
| Pin 35 | RB5 — Port B bit 5 |
| Pin 36 | RB6 — Port B bit 6 / PGC (ICSP clock) |
| Pin 37 | RB7 — Port B bit 7 / PGD (ICSP data) |
| Pin 38 | RC0 — Port C bit 0 / T1OSO |
| Pin 39 | RC1 — Port C bit 1 / T1OSI / CCP2 |
| Pin 40 | RC2 — Port C bit 2 / CCP1 |
| Pin 41 | RC3 — Port C bit 3 / SCL |
| Pin 42 | RC4 — Port C bit 4 / SDA |
| Pin 43 | RC5 — Port C bit 5 / SDO |
| Pin 44 | RC6 — Port C bit 6 / TX1 |
| Pin 45 | RC7 — Port C bit 7 / RX1 |
| Pin 46 | VSS — Digital ground |
| Pin 47 | VDD — Digital supply |
| Pin 48 | RD0 — Port D bit 0 |
| Pin 49 | RD1 — Port D bit 1 |
| Pin 50 | RD2 — Port D bit 2 |
| Pin 51 | RD3 — Port D bit 3 |
| Pin 52 | RD4 — Port D bit 4 / IC2 |
| Pin 53 | RD5 — Port D bit 5 / PWM |
| Pin 54 | RD6 — Port D bit 6 |
| Pin 55 | RD7 — Port D bit 7 |
| Pin 56 | VSS — Digital ground |
| Pin 57 | VDD — Digital supply |
| Pin 58 | RE0 — Port E bit 0 / AN5 |
| Pin 59 | RE1 — Port E bit 1 / AN6 |
| Pin 60 | RE2 — Port E bit 2 / AN7 |
| Pin 61 | RE3 — Port E bit 3 |
| Pin 62 | RE4 — Port E bit 4 |
| Pin 63 | RE5 — Port E bit 5 |
| Pin 64 | RE6 — Port E bit 6 |
| Pin 65 | RE7 — Port E bit 7 |
| Pin 66 | VSS — Digital ground |
| Pin 67 | VDD — Digital supply |
| Pin 68 | RF0 — Port F bit 0 / AN8 |
| Pin 69 | RF1 — Port F bit 1 / AN9 |
| Pin 70 | RF2 — Port F bit 2 / AN10 |
| Pin 71 | RF3 — Port F bit 3 / AN11 |
| Pin 72 | RF4 — Port F bit 4 / AN12 |
| Pin 73 | RF5 — Port F bit 5 / AN13 |
| Pin 74 | RF6 — Port F bit 6 / AN14 |
| Pin 75 | RF7 — Port F bit 7 / AN15 |
| Pin 76 | RG0 — Port G bit 0 (alternate) |
| Pin 77 | RG1 — Port G bit 1 (alternate) |
| Pin 78 | RG2 — Port G bit 2 (alternate) |
| Pin 79 | RG3 — Port G bit 3 (alternate) |
| Pin 80 | RG4 — Port G bit 4 (alternate) |
Typical Applications
PIC18LF8585-I/PT is suitable for 6 applications: Industrial Automation Controllers, HVAC and Appliance Control, Automotive Body and Instrument Modules, Sensor Conditioning and Data Logger Nodes, Medical Monitoring Devices (Non-Implantable), General-Purpose Embedded Control Boards.
Industrial Automation Controllers
The PIC18LF8585-I/PT fits industrial automation because it integrates 68 I/O, dual USART, and CAN-class peripherals needed for PLC expansion racks, sensor hubs, and motor-control daughter cards. Its 48 KB Flash supports ladder-logic interpreters or MODBUS firmware, while 3328 bytes of RAM is adequate for protocol buffers. The 40 MHz core delivers deterministic 10 MIPS throughput, important for closed-loop PID running alongside communication stacks. The 80-TQFP footprint also gives generous ground and power pins, easing PCB layout for noisy factory environments with proper bulk decoupling.
Recommended
HVAC and Appliance Control
The PIC18LF8585-I/PT is well matched to HVAC and appliance control boards where a single MCU must read multiple temperature/pressure sensors, drive TRIAC-controlled loads, and run a user-interface keypad/LCD. Its 16-channel 10-bit ADC handles NTC thermistor arrays, while CCP/ECCP modules generate the zero-cross-switched PWM that drives compressors and fans. Industrial -40C to +85C rating covers indoor/outdoor unit deployments. The wide 80-TQFP package gives layout room for optoisolation barriers around mains switching.
Recommended
Automotive Body and Instrument Modules
The PIC18LF8585-I/PT powers automotive body controllers, instrument clusters, and HVAC head units where 68 I/O drive stepper-motor gauges, switch matrices, and CAN/LIN transceivers. Its 48 KB Flash stores cluster graphics and diagnostic routines, and the enhanced PIC18 peripheral set (CCP, MSSP, dual USART) interfaces with body-control gateways. Note this is the industrial -40C to +85C grade; AEC-Q100 designs should select an automotive-qualified variant or migrate to a PIC18 K-series auto part.
Recommended
Sensor Conditioning and Data Logger Nodes
The PIC18LF8585-I/PT acts as a multi-channel sensor-conditioning node for industrial monitoring and remote telemetry. Its 16-channel ADC with internal reference reads bridge-type pressure/flow sensors, while the 3328-byte RAM buffers time-stamped samples before forwarding over USART or SPI to a gateway. Self-programmable Flash enables OTA firmware updates for remote sensor fleets. The 80-TQFP package allows short analog trace lengths and dedicated AVSS/AVDD pairs for low-noise measurements.
Recommended
Medical Monitoring Devices (Non-Implantable)
The PIC18LF8585-I/PT suits non-implantable medical monitors such as infusion-pump controllers, patient-bedside displays, and physiotherapy devices where a reliable 8-bit core, deterministic interrupt latency, and multiple USART/SPI ports are needed. Its 48 KB Flash stores therapy protocols and audit logs in tamper-resistant memory, and dual USART handles simultaneous host-link and bedside-display communication. Designers must still perform full IEC 60730 / IEC 60601 software-validation work; this grade is industrial (-40C to +85C).
Recommended
General-Purpose Embedded Control Boards
The PIC18LF8585-I/PT is a strong fit for general-purpose embedded boards such as custom test fixtures, education platforms, and prototyping controllers where Flash reprogrammability, ICSP debug, and a wide pin count simplify I/O expansion. MPLAB X IDE plus a PICkit or ICD programmer supports in-circuit debug through the PGD/PGC pins mapped on the 80-TQFP. Code portability across the PIC18 family means firmware written for smaller PIC18F452-class parts migrates upward with minimal changes.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF8585-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F8585-I/PT | PIC18LF8585T-I/PT | PIC18LF6680T-I/PT | PIC18LF8525-I/PT | PIC18LF8527T-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 80-pin TQFP (12x12 mm) | 80-pin TQFP (12x12 mm) - same | 80-pin TQFP (12x12 mm) - same | 80-pin TQFP (12x12 mm) - same | 80-pin TQFP (12x12 mm) - same | 80-pin TQFP (12x12 mm) - same |
| Flash Memory | 48 KB | 48 KB | 48 KB | 32 KB | 48 KB | 48 KB |
| RAM | 3328 bytes | 3328 bytes | 3328 bytes | ~2048 bytes | ~3328 bytes | ~3328 bytes |
| Max CPU Speed | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Operating Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) | 2.0 V to 5.5 V (LF) |
| I/O Pins | 68 | 68 | 68 | ~52 | 68 | ~68 |
| Temperature Grade | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) | Industrial (-40C to +85C) |
| Lifecycle Status | ACTIVE | ACTIVE | ACTIVE | ACTIVE (verify stock) | ACTIVE (verify stock) | ACTIVE (verify stock) |
Key Differentiators
- Higher Flash and RAM than PIC18LF6680 in the same package (vs PIC18LF6680T-I/PT)
- Drop-in 80-TQFP pinout across the PIC18F8585 silicon family (vs PIC18F8585-I/PT)
- 68 I/O pins in TQFP-80 vs typical 28-40 pins on smaller PIC18F parts (vs PIC18F452-I/P (DIP-40))
Design Notes
Decouple every VDD/VSS pair on the 80-TQFP with a 0.1 uF ceramic plus 10 uF bulk; place AVDD/AVSS pins on a quiet analog rail and add a ferrite bead if analog and digital VDD share a source. Hold MCLR high through a 10 kohm pull-up and a 100 nF cap to ground; do not leave MCLR floating or the device may spuriously reset.
Keep the 40 MHz crystal/EC traces short (under 10 mm) and guard the OSC1/OSC2 pins with a ground ring. Route RB6/PGC and RB7/PGD to a 0.1 inch header or test pad so ICSP remains accessible in production. For mixed-signal designs, dedicate one PCB layer to ground and avoid routing analog traces under the TQFP paddle area.
Always set configuration bits (FOSC, WDTE, LVP, DEBUG) explicitly in source; relying on factory defaults may enable low-voltage programming or disable the watchdog incorrectly. Verify the LF (low-voltage) silicon actually operates down to 2 V in your application - many PIC18F peripherals require >= 4.2 V at VDD for full spec compliance.
At 40 MHz the PIC18LF8585-I/PT draws roughly 50-60 mA active - far below thermal limits for TQFP-80, but at extended temperature (85C) ensure the IC has continuous ground copper under the exposed area and adequate airflow. Estimated: with 60 mA at 5 V (0.3 W) the junction rise on TQFP-80 (~40 C/W theta_JA on a 4-layer board) is only ~12 C above ambient, well within -40 to +85 C rating.
Compliance Information
Verified Web Data shows LEAD FREE package code; Microchip publishes RoHS and REACH compliance. Industrial temperature grade only - not AEC-Q100 qualified; automotive designs must choose an automotive-grade variant.