PIC18LF8621T-I/PT - 8-bit 40MHz 64KB Flash MCU 80-TQFP | Microchip
MPN: PIC18LF8621T-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $5.28 | $5.28 |
| 10 | $4.95 | $49.50 |
| 100 | $4.42 | $442.00 |
| 500 | $3.89 | $1,945.00 |
| 1,000 | $3.45 | $3,450.00 |
PIC18LF8621T-I/PT Overview
A PIC microcontroller is a compact, programmable microcontroller unit (MCU) that combines a CPU core, non-volatile Flash program memory, SRAM data memory, and a rich set of on-chip peripherals (ADC, timers, UART/SPI/I2C, PWM, I/O ports) on a single silicon die. PIC18 devices belong to the enhanced mid-range MCU tier in the broader taxonomy of microcontrollers (MCU -> 8-bit MCU -> PIC -> PIC18F family -> PIC18F high-pin-count). The LF suffix denotes the low-voltage F-series variants that extend operation down to a lower VDD minimum while retaining Flash-based self-programmability.
Key features of this device include 54 digital I/O pins, an internal 8 MHz / 32 kHz oscillator, two analog comparators, a 10-bit A/D converter with up to 16 input channels, two MSSP (SPI/I2C) modules, two enhanced USART modules, four timers (Timer0/1/2/3), two capture/compare/PWM modules, and self-programming Flash with ICSP (In-Circuit Serial Programming). The "T" suffix indicates tape-and-reel packaging, while the "I" suffix denotes the industrial -40C to +85C operating temperature range.
Typical applications include industrial control and HMI panels, automotive body and chassis subsystems, instrumentation and data loggers, USB/HID peripherals, sensor-conditioning front ends, and home appliance controllers. The high pin count (80-pin) and generous 64 KB Flash make it suitable for protocol stacks (e.g., CAN, USB, TCP/IP) running on a single MCU. When designing with this part, verify the device errata sheet and reference manual (DS39626) for peripheral limits, and budget code space carefully because the 64 KB Flash holds a modest program footprint.
This page synthesizes distributor pricing, same-family drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18LF8621T-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 PIC18LF8621T-I/PT (same form factor and footprint) — differing in I/O Pins, Package, ADC, Core Architecture, Operating Temperature.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF8621-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF8722T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF8527T-I/PT
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC18F8621T-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF8585-I/PT
✅ Drop-In✓ In Stock
$6.2 / Unit
View Datasheet →PIC18LF6680T-I/PT
✅ Drop-In✓ In Stock
$6.4 / Unit
View Datasheet →PIC18LF8621T-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 (8-bit RISC) |
| Program Memory Type | Flash |
| Program Memory Size | 64 KB (32K x 16) |
| RAM Size | 3840 bytes |
| Maximum Clock Frequency | 40 MHz |
| Supply Voltage Range | 4.2 V to 5.5 V |
| I/O Pins | 54 |
| Package | 80-TQFP (12x12 mm) |
| Mounting Type | Surface Mount |
| Operating Temperature Range | -40C to +85C (Industrial) |
| A/D Converter | 10-bit |
| Communication Interfaces | MSSP (SPI/I2C), EUSART, CAN |
| Timers | 4 (Timer0/1/2/3) |
| CCP/PWM Modules | 2 |
| ICSP / Self-Programming | Yes |
| RoHS Status | Compliant (LEAD FREE per datasheet) |
PIC18LF8621T-I/PT 80-tqfp (12x12 mm) Pin Configuration Guide
Pin configuration for PIC18LF8621T-I/PT (80-tqfp (12x12 mm) package). This digital IC includes GPIO, communication interfaces (UART, SPI, I2C), and power pins. Refer to the manufacturer datasheet for alternate pin functions and configuration options. Essential for embedded system design and PCB layout.
No detailed pinout data available for PIC18LF8621T-I/PT.
Refer to the datasheet for full pin configuration.
Typical Applications
PIC18LF8621T-I/PT is suitable for 6 applications: Industrial Control & HMI, Automotive Body & Chassis ECUs, Instrumentation & Data Logging, Home Appliance Controllers, USB / HID Peripherals, Sensor Conditioning Front Ends.
Industrial Control & HMI
The PIC18LF8621T-I/PT fits industrial control and HMI panels with its 54 I/O pins, 40 MHz core, and 64 KB Flash. Why it fits: the 8-bit PIC18 instruction set executes deterministic control loops in <100 ns per instruction, while the 3840 bytes RAM supports small protocol stacks (Modbus RTU, ASCII command parsers). How it is used: drive keypad matrices and character LCDs directly from PORTB/PORTD, run a 10 ms scan loop, and host UART to a master PLC. Trade-off: the 5 V VDD requires a regulated supply above 4.2 V, but EMI immunity is better than 3.3 V parts on noisy factory floors.
Recommended
Automotive Body & Chassis ECUs
The PIC18LF8621T-I/PT can serve as a body-electronics ECU for non-safety subsystems (interior lighting, mirror control, seat modules). Why it fits: 54 I/O pins drive multiple MOSFET bridges and sense switch inputs, while 64 KB Flash holds CAN-capable firmware stacks. How it is used: sit between a CAN transceiver (e.g., MCP2551) and the body wiring harness, multiplex PWM outputs for LED dimming, and run timer-driven debouncing. Trade-off: this part is industrial-grade (I-suffix, -40 to +85 C); for AEC-Q100 applications, choose a Q-graded PIC18 variant from Microchip's automotive catalog.
Recommended
Instrumentation & Data Logging
The PIC18LF8621T-I/PT is suitable for multi-channel instrumentation and battery-powered data loggers. Why it fits: the 10-bit ADC with up to 16 input channels (via port-muxed analog pins), combined with 3840 bytes RAM and 64 KB Flash, supports sampling multiple sensors at 1-10 kHz with on-chip buffering. How it is used: scan thermocouples, strain gauges, or 4-20 mA loops through the ADC; store formatted records in RAM; flush to external EEPROM/SD via SPI. Trade-off: only 3840 bytes RAM limits continuous-stream buffering, so a typical design buffers one sample frame and flushes synchronously.
Recommended
Home Appliance Controllers
The PIC18LF8621T-I/PT powers washing-machine, dishwasher, and HVAC control boards. Why it fits: the high pin count accommodates multiplexed 7-segment displays, triac drivers, and zero-cross detection, while the industrial temperature range (-40 to +85 C) tolerates appliance thermal stress. How it is used: drive triac optocouplers (MOC3021) for heater/valve control; read thermistors via the ADC; run a state machine in the main loop. Trade-off: 5 V VDD needs a small offline SMPS, but the LF family's nanoWatt sleep modes keep standby power low for energy-star appliances.
Recommended
USB / HID Peripherals
The PIC18LF8621T-I/PT (with PIC18 USB silicon) is well-suited for USB-HID class peripherals such as custom keypads, jog wheels, and indicator panels. Why it fits: full-speed USB 2.0 device support, 64 KB Flash for HID descriptors and application logic, 10-bit ADC for analog inputs. How it is used: enumerate as HID, report key/joystick states via interrupt-IN endpoint, drive LEDs via PWM/CCP. Trade-off: the 5 V VDD allows direct USB VBUS sensing without level shifting; the 64 KB Flash fits typical HID class stacks with room for vendor-specific report descriptors.
Recommended
Sensor Conditioning Front Ends
The PIC18LF8621T-I/PT integrates multi-sensor signal conditioning in industrial gateways. Why it fits: dual MSSP (SPI/I2C) ports let the MCU bridge SPI sensors (e.g., MEMS accelerometers) to I2C peripherals (e.g., EEPROM), while 54 I/O drive discrete status LEDs and relay drivers. How it is used: read SPI sensors via MSSP1, store calibration constants in I2C EEPROM, publish processed readings over UART/CAN to the host. Trade-off: 40 MHz gives 10 MIPS, which is more than enough for 1 kHz sensor fusion loops; however, the 3840 bytes RAM caps simultaneous active sensor buffers.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF8621T-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF8621-I/PT | PIC18LF8722T-I/PT | PIC18LF8527T-I/PT | PIC18F8621T-I/PT | PIC18LF8585-I/PT |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 80-TQFP (12x12 mm) | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same | 80-TQFP (12x12 mm) - same |
| Flash Memory | 64 KB (32K x 16) | 64 KB | 128 KB | 48 KB | 64 KB | 48 KB |
| RAM | 3840 bytes | 3840 bytes | 3936 bytes | 3328 bytes | 3840 bytes | 3328 bytes |
| Max Clock Frequency | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| Supply Voltage | 4.2 V to 5.5 V | 4.2 V to 5.5 V | 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 |
| I/O Pins | 54 | 54 | 54 | 54 | 54 | 54 |
| A/D Converter | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit |
| Operating Temperature | -40C to +85C (Industrial) | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Highest Flash headroom in 80-TQFP family with same pinout (vs PIC18LF8527T-I/PT)
- Industry-standard 80-TQFP package enables pin-compatible migration (vs PIC18LF8585-I/PT)
- Low-voltage LF family supports nanoWatt power modes (vs PIC18F8621T-I/PT)
Design Notes
The PIC18LF8621T-I/PT requires VDD in the range 4.2 V to 5.5 V. Add a 100 nF decoupling capacitor close to each VDD/VDDCORE pin pair, plus a 10 uF bulk capacitor at the regulator output. The LF family supports nanoWatt sleep modes (Sleep, Idle, and RTCC modes) that draw only microamps; combine with a low-dropout regulator (e.g., MCP1700) and a digital load switch to achieve standby power below 100 uA.
Route the 80-TQFP package with 0.4 mm pitch escape routing; the TQFP has gull-wing leads on all four sides. Place a continuous ground plane on layer 2 directly under the MCU for thermal dissipation (the exposed pad option is not present on this part; rely on copper pour and adequate via stitching to the ground plane). Keep analog traces (ADC inputs) routed away from digital switching traces, especially PWM and CCP outputs near the ADC channels.
Do not connect any pin to a voltage above VDD or below VSS without current-limiting; the PIC18 digital inputs are 5 V tolerant only at VDD = 5 V (clamped via ESD diodes). When using the ADC, place a 1 kHz or lower input bandwidth filter to avoid aliasing; the 10-bit ADC is unipolar 0-VREF and ratiometric. Configure CONFIG words (oscillator, watchdog, brown-out) explicitly in source code; the factory-default CONFIG may not match your application's needs and can cause bootloader or oscillator startup failures.
Place the 40 MHz crystal (or ceramic resonator) within 5 mm of OSC1/OSC2 with short, symmetric traces surrounded by ground pour to minimize EMI. Add 22-33 pF load capacitors per crystal manufacturer recommendation. For USB applications, the D+/D- traces must be 90 ohm differential impedance-matched and routed in parallel to a ground reference plane; mismatched impedance degrades signal integrity at full-speed (12 Mbps).
Compliance Information
LEAD FREE per Microchip product marking and datasheet. RoHS and REACH compliance per Microchip product page. Not AEC-Q100 qualified; this part is industrial-grade (I-suffix, -40 to +85 C).
