PIC18LF252-I/SO - 8-Bit 40MHz PIC18 MCU 32KB Flash 28-SOIC | Microchip
MPN: PIC18LF252-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.73 | $10.73 |
| 10 | $9.95 | $99.50 |
| 100 | $9.18 | $918.00 |
| 500 | $8.42 | $4,210.00 |
| 1,000 | $7.65 | $7,650.00 |
PIC18LF252-I/SO Overview
An 8-bit microcontroller (MCU) is a single-chip computer that integrates a CPU, program memory (ROM/Flash), data memory (RAM), and peripherals on one silicon die; the PIC18 family extends Microchip's baseline PIC architecture with 16-bit-wide instruction words and an enhanced instruction set to deliver roughly 4x the performance of PIC16 devices at the same clock. The "LF" suffix denotes an extended low-voltage part, and the "F" suffix indicates Flash program memory.
Key features of the PIC18LF252-I/SO include 32 KB self-programmable Flash with 100K erase/write cycles endurance, an internal oscillator block, ICD (In-Circuit Debugger) support, nanoWatt power management with idle and sleep modes, and a 10-bit ADC with up to 5 channels. The 28-SOIC industrial-temperature range (-40C to +85C) is well-suited to factory-floor equipment and outdoor enclosures, while the wide supply range lets the same firmware serve both 3.3V and 5V rails.
Typical applications include industrial control and sensor-interface boards, small home appliances, automotive body electronics subsystems, USB-to-UART bridges when paired with an external transceiver, and low-cost user-interface panels with character LCDs and keypads. The PIC18 instruction set's compact C-friendly architecture also makes this part a long-time favorite for legacy code migration and hobbyist projects.
When designing with this device, allocate the ADC reference and AVdd pin filtering per the manufacturer datasheet, place a 100 nF decoupling cap on Vdd with a 10 uF bulk cap on the board, and confirm that the programming/debug header matches the ICSP pinout for the 28-pin SOIC variant. Engineering judgment is required to balance code size, ADC channels, and I/O count for your specific BOM.
This page synthesizes distributor pricing from DigiKey and Mouser, drop-in replacement alternatives in the same 28-SOIC footprint, and practical design notes that are not collated on the manufacturer datasheet landing page.
Drop-in alternatives for PIC18LF252-I/SO — 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 PIC18LF252-I/SO (same form factor and footprint) — differing in ADC, Package, I/O Pins, Operating Temperature, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F252-I/SO
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →PIC18LF252-I/SP
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF2520-I/SO
✅ Drop-In✓ In Stock
$4.47 / Unit
View Datasheet →PIC18LF2525-I/SO
✅ Drop-In✓ In Stock
$3.51 / Unit
View Datasheet →PIC18LF242-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18LF252-I/SO Maximum Ratings & Electrical Characteristics
| Product Type | 8-bit Microcontroller (MCU) |
| Core Architecture | PIC18 (Enhanced RISC) |
| Instruction Set Width | 16-bit (8-bit data path) |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Program Memory (Flash) | 32 KB (16K x 16 words) |
| RAM | 1536 bytes |
| EEPROM | 256 bytes |
| Supply Voltage Range | 2.0 V to 5.5 V |
| I/O Pins | 23 |
| ADC | 10-bit, 5 channels |
| Communication Interfaces | USART, MSSP (SPI / I2C) |
| Timers | 4 (Timer0, Timer1, Timer2, Timer3) |
| Package | 28-pin SOIC (SO), wide-body, 7.50 mm |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Mounting Type | Surface Mount |
PIC18LF252-I/SO Pin Configuration
| Pin 1 | /MCLR — Master Clear (reset) input, active low |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input 0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input 1 |
| Pin 4 | RA2/AN2/Vref- — PORTA bit 2 / analog input 2 / ADC Vref- |
| Pin 5 | RA3/AN3/Vref+ — PORTA bit 3 / analog input 3 / ADC Vref+ |
| Pin 6 | RA4/T0CKI — PORTA bit 4 / Timer0 clock input |
| Pin 7 | RA5/AN4/SS — PORTA bit 5 / analog input 4 / SPI slave select |
| Pin 8 | Vss — Ground reference |
| Pin 9 | OSC1/CLKI — Oscillator crystal input / external clock in |
| Pin 10 | OSC2/CLKO — Oscillator crystal output / clock out |
| Pin 11 | RC0/T1OSO — PORTC bit 0 / Timer1 oscillator output |
| Pin 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator in / CCP2 |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / Capture-Compare-PWM 1 |
| Pin 14 | RC3/SCK/SCL — PORTC bit 3 / SPI clock / I2C clock |
| Pin 15 | RC4/SDI/SDA — PORTC bit 4 / SPI data in / I2C data |
| Pin 16 | RC5/SDO — PORTC bit 5 / SPI data out |
| Pin 17 | RC6/TX/CK — PORTC bit 6 / USART TX / clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / USART RX / data |
| Pin 19 | Vss — Ground reference |
| Pin 20 | Vdd — Positive supply (2.0V to 5.5V) |
| Pin 21 | RB0/INT0 — PORTB bit 0 / external interrupt 0 |
| Pin 22 | RB1/INT1 — PORTB bit 1 / external interrupt 1 |
| Pin 23 | RB2/INT2 — PORTB bit 2 / external interrupt 2 |
| Pin 24 | RB3/CCP2 — PORTB bit 3 / Capture-Compare-PWM 2 |
| Pin 25 | RB4 — PORTB bit 4 / interrupt-on-change |
| Pin 26 | RB5/PGM — PORTB bit 5 / LVP programming |
| Pin 27 | RB6/PGC — PORTB bit 6 / ICD clock / in-circuit debug |
| Pin 28 | RB7/PGD — PORTB bit 7 / ICD data / in-circuit debug |
Typical Applications
PIC18LF252-I/SO is suitable for 7 applications: Industrial Sensor Interface Board, Small Home Appliance Control, USB-to-UART Bridge Dongle, Character LCD User Interface Panel, Automotive Body Electronics Subsystem, Battery-Powered Remote Sensor Node, Legacy Firmware Migration Platform.
Industrial Sensor Interface Board
The PIC18LF252-I/SO fits industrial sensor interface boards because its 10-bit 5-channel ADC, USART, and I2C/SPI peripherals let a single chip read analog sensors and forward data to a master PLC or gateway. With 32 KB Flash, 1536 bytes SRAM, and the LF 2.0V-5.5V supply range, it can run from a 3.3V regulated rail or a 5V backplane. Placed near field wiring with proper isolation, it provides deterministic 10 MIPS control. Unlike higher-end Cortex-M0 parts, the PIC18LF252 keeps legacy firmware compatibility and ICD debug, simplifying long-life industrial SKUs.
Recommended
Small Home Appliance Control
The PIC18LF252-I/SO is a strong fit for small home appliances such as coffee makers, bread machines, and countertop ovens because its 28-SOIC footprint, 23 I/O pins, and 4 timers handle keypad scanning, character LCD drive, buzzer PWM, and triac-fired heater control in one part. The 10 MIPS throughput keeps response snappy even with multiplexed displays, and the LF 2.0V-5.5V supply range supports both rectified-5V and 3.3V logic supplies. Engineers should derate output drive when switching 100-200 mA triac gates and add zero-cross optocouplers for safety.
Recommended
USB-to-UART Bridge Dongle
The PIC18LF252-I/SO serves well in legacy USB-to-UART bridge designs when paired with an external USB transceiver such as the MCP2200 or FTDI FT232, since the PIC18 core provides the serial side at 40 MHz / 10 MIPS while the external transceiver handles USB enumeration. The 32 KB Flash holds CDC stack glue and protocol translators, and the 2.0V-5.5V supply range supports both 3.3V and 5V UART targets. Compared with a pure PIC18F2550 USB-onboard solution, this LF252 design sacrifices native USB for cost and supply flexibility.
Recommended
Character LCD User Interface Panel
The PIC18LF252-I/SO drives character LCDs (HD44780-compatible 16x2 / 20x4 displays) and matrix keypads through its 23 I/O pins, 4 timers, and PWM peripherals, making it ideal for low-cost UI panels in vending machines, kiosks, and instrument front panels. The 32 KB Flash accommodates multilingual UI strings and menu trees, while the 1536 bytes SRAM holds display buffers and debounced key state. Unlike ARM Cortex-M alternatives, the PIC18 retains proven long-term firmware stability and a single-wire ICD debug interface that survives field rework.
Recommended
Automotive Body Electronics Subsystem
The PIC18LF252-I/SO appears in automotive body-electronics subsystems such as interior lighting controllers, mirror adjusters, and HVAC blend-door drivers because its 28-SOIC wide-body package handles thermal cycling, its 23 I/O pins drive multiple loads via MOSFETs, and its 10-bit ADC reads position sensors and thermistors. The 2.0V-5.5V supply survives cold-crank and load-dump events with proper external regulation. Although not AEC-Q100 qualified, the part is widely used in non-safety body modules; for safety-critical ECUs migrate to PIC18F-K40 Q1 variants.
Recommended
Battery-Powered Remote Sensor Node
The PIC18LF252-I/SO is well suited to battery-powered remote sensor nodes because of its low-voltage LF (2.0V min) operation, nanoWatt power-management modes with sub-microamp sleep current, and ability to wake on interrupt from a sensor or timer. The 32 KB Flash and 1536 bytes SRAM handle modest protocol stacks (e.g., Modbus RTU, lightweight mesh) and 10-bit ADC readings on a 3.6V lithium primary cell. Two AA cells in series can power the node down to 2.0V, with the PIC18 entering sleep between transmissions to extend runtime to years.
Recommended
Legacy Firmware Migration Platform
The PIC18LF252-I/SO remains the migration target of choice for engineers modernizing PIC16-based legacy designs that need more code space, more I/O, and a 10 MIPS upgrade without rewriting the entire application in a new architecture. With 32 KB Flash and the PIC18 instruction set's C-friendly addressing, legacy assembly code can be incrementally ported while keeping the same ICD debug tools, the same ICSP programming header, and the same 28-SOIC land pattern. This minimizes PCB redesign risk and lets product teams refresh firmware over a long production lifetime.
Recommended
Recommended Products Summary
Engineering reference data for PIC18LF252-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F252-I/SO | PIC18LF252-I/SP | PIC18LF2520-I/SO | PIC18LF2525-I/SO | PIC18LF242-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (SO) wide-body | 28-SOIC (SO) wide-body | 28-PDIP (SP) - through-hole, NOT same footprint as SOIC | 28-SOIC (SO) wide-body - same | 28-SOIC (SO) wide-body - same | 28-SOIC (SO) wide-body - same |
| Program Memory (Flash) | 32 KB | 32 KB | 32 KB | 32 KB | 32-64 KB | 16 KB (-50%) |
| Supply Voltage Range | 2.0 V to 5.5 V (LF) | 4.2 V to 5.5 V (standard F) | 2.0 V to 5.5 V (LF) | 1.8 V to 3.6 V (LF) | 1.8 V to 3.6 V (LF) | 2.0 V to 5.5 V (LF) |
| Maximum CPU Speed | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 64 MHz / 16 MIPS | 64 MHz / 16 MIPS | 40 MHz / 10 MIPS |
| RAM | 1536 bytes | 1536 bytes | 1536 bytes | 2048 bytes | 2048-3936 bytes | 768 bytes |
| ADC | 10-bit, 5 channels | 10-bit, 5 channels | 10-bit, 5 channels | 10-bit, 8 channels | 10-bit, 11 channels | 10-bit, 5 channels |
| Price (1 unit, USD) | $10.73 | $9.95 (typical) | $11.20 (PDIP) | $5.40 (newer, lower cost) | $5.90 (newer) | $8.85 |
Key Differentiators
- Extended low-voltage operation down to 2.0V (vs PIC18F252-I/SO)
- Newer-generation K-series migration path in same footprint (vs PIC18LF2525-I/SO)
- Drop-in 28-SOIC family compatibility (vs PIC18LF242-I/SO)
Design Notes
Place a 100 nF ceramic decoupling capacitor as close as possible to the Vdd pin (pin 20) and a bulk 10 uF electrolytic or ceramic on the same node. For the AVdd reference path, add a 10 uH ferrite bead and a separate 100 nF cap on the analog supply rail if precision ADC readings are required. The LF variant's 2.0 V to 5.5 V range means you can run from two AA cells or a 3.3 V regulator without level shifters; verify brown-out reset (BOR) settings in CONFIG registers to match your supply startup profile.
The 28-SOIC wide-body footprint (1.27 mm pitch, ~7.5 mm body width) is the same land pattern as PIC18F252, PIC18LF2520, PIC18LF2525, and PIC18F25K22 in 28-SOIC, allowing direct PCB migration across these generations. Keep the ICSP header (PGC on RB6, PGD on RB7) routed with short traces to a 6-pin header on the board edge for in-circuit debug, and reserve a 4.7 kohm pull-up on RB6/PGC per Microchip's ICD recommendations.
Do not connect unused I/O pins directly to ground or Vdd - configure them as outputs and leave them open, or set them as inputs with internal weak pull-ups enabled. The /MCLR pin (pin 1) must have a 10 kohm pull-up to Vdd; without it, the device will not start reliably. When using the internal oscillator block, configure the IOFS (Internal Oscillator Frequency Select) bits correctly for your target Fosc, or use the HF-INTOSC with PLL for higher frequencies. Finally, disable the LVP (Low-Voltage Programming) bit in CONFIG3H if you do not need it, to free RB5 as general I/O.
Compliance Information
RoHS and lead-free compliant per Microchip product page and DigiKey listing. Not AEC-Q100 qualified - migrate to PIC18F25K40-I/SO Q1 for automotive. Halogen-free status not specified in the verified web data.
