PIC18F252T-I/SO - 8-Bit 40MHz 32KB Flash MCU 28-SOIC | Microchip
MPN: PIC18F252T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $10.59 | $10.59 |
| 10 | $9.51 | $95.10 |
| 100 | $8.49 | $849.00 |
| 500 | $7.62 | $3,810.00 |
| 1,000 | $6.91 | $6,910.00 |
PIC18F252T-I/SO Overview
What is a PIC18F 8-bit microcontroller? An 8-bit MCU executes instructions on 8-bit data paths at modest clock rates (typically 10–40 MIPS) and is widely used in cost-sensitive embedded control. The PIC18F family is Microchip's enhanced PIC architecture, upwards-compatible with the PIC16C5X, PIC12CXXX, and PIC16CXX lines, and adds a C-compiler-friendly instruction set, hardware multiply, and extended peripherals while remaining RISC-based. Within Microchip's taxonomy it sits under PIC microcontroller -> 8-bit MCU -> microcontroller (MCU) -> embedded processor -> semiconductor. The PIC18F252 specifically targets mid-range applications needing A/D conversion, PWM, and serial communication without moving to a 16-bit dsPIC or 32-bit ARM Cortex part.
Key features include 32 KB (16K × 16) self-programmable Flash for in-application firmware updates, 256 bytes of EEPROM for non-volatile parameter storage, 5 channels of 10-bit ADC for sensor acquisition, a USART, MSSP (configurable as 3-wire SPI or I²C), 2 capture/compare/PWM modules for motor and lighting control, and 2 analog comparators. The wide 4.2 V–5.5 V supply range and industrial-grade -40 °C to +85 °C operating temperature suit factory-floor and automotive under-hood designs.
Architecturally, the device uses Harvard-style separate program and data buses, an 8-bit data path, a 16-bit instruction word, and CMOS FLASH technology to deliver strong code density and low dynamic power. The enhanced core adds 77 single-word instructions, hardware multiply, and a software-stack model that simplifies C compiler code generation versus legacy PIC16 designs.
Typical applications include industrial sensor conditioning, motor control with PWM-driven bridges, HVAC thermostat logic, automotive body controllers (under-hood temperature derated), USB-to-UART bridges when paired with a separate PHY, and consumer appliances requiring user-interface key-scans. The PIC18F252T-I/SO fits wherever deterministic 8-bit control, on-chip EEPROM, and modest analog integration are needed.
When designing with this MCU, choose a 4 MHz–40 MHz crystal or resonator for the primary oscillator, populate the ICSP ICD pins for in-circuit debug, and route AVSS/VDD pairs to a quiet analog ground for best ADC accuracy. Always check the latest Microchip PIC18F252 errata and DS39576 family documentation before locking production firmware.
This page consolidates verified distributor pricing, identical-footprint drop-in alternates, and engineering notes that go beyond the bare datasheet, helping procurement and design engineers evaluate the PIC18F252T-I/SO in a single view.
Drop-in alternatives for PIC18F252T-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 PIC18F252T-I/SO (same form factor and footprint) — differing in Package, Core Architecture, Operating Temperature, ADC, Self-Programming.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F252-I/SO
✅ Drop-In✓ In Stock
$3.95 / Unit
View Datasheet →PIC18F252-E/SO
✅ Drop-In✓ In Stock
$5.78 / Unit
View Datasheet →PIC18F252T-E/SO
✅ Drop-In ⚠️ Specs Unverified📋 Reference alternative (not in catalog)
PIC18F242-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.5 / Unit
View Datasheet →PIC18F242T-I/SO
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC18F252T-I/SO Maximum Ratings & Electrical Characteristics
| Family | PIC 18F |
| Core Architecture | 8-bit PIC enhanced RISC |
| CPU Speed | 40 MHz (10 MIPS) |
| Instruction Cycle Time | 100 ns |
| Instruction Set Size | 77 single-word instructions |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data SRAM | 1536 bytes |
| Data EEPROM | 256 bytes |
| Number of I/O Pins | 23 |
| ADC | 10-bit, 5 channels |
| Supply Voltage Range | 4.2 V to 5.5 V |
| Operating Temperature Range | -40 C to +85 C (Industrial) |
| Package | 28-SOIC (Wide Body, SO) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (per Microchip SOIC profile) |
| ROM Type | Flash |
| Communication Peripherals | USART, MSSP (SPI / I2C) |
| Timers/PWM | 2 CCP modules |
| Comparators | 2 analog comparators |
| RoHS Status | Compliant |
PIC18F252T-I/SO Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (reset) input or programming voltage; tied to VDD via 10 kOhm |
| Pin 2 | RA0/AN0 — Digital I/O or analog input channel 0 |
| Pin 3 | RA1/AN1 — Digital I/O or analog input channel 1 |
| Pin 4 | RA2/AN2 — Digital I/O or analog input channel 2 |
| Pin 5 | RA3/AN3/VREF+ — Digital I/O, analog input, or ADC positive reference |
| Pin 6 | RA4/T0CKI — Digital I/O or Timer0 clock input |
| Pin 7 | RA5/AN4/SS/LVDIN — Digital I/O, analog input, SPI slave select, or LVD input |
| Pin 8 | OSC1/CLKIN — Crystal oscillator input or external clock input |
| Pin 9 | OSC2/CLKOUT — Crystal oscillator output or clock output |
| Pin 10 | RC0/T1OSO/T1CKI — Digital I/O or Timer1 oscillator I/O |
| Pin 11 | RC1/T1OSI/CCP2 — Digital I/O, Timer1 oscillator input, or CCP2 |
| Pin 12 | RC2/CCP1 — Digital I/O or CCP1 (PWM/capture/compare) |
| Pin 13 | RC3/SCK/SCL — Digital I/O, MSSP SPI clock, or I2C clock |
| Pin 14 | RC4/SDI/SDA — Digital I/O, MSSP SPI data in, or I2C data |
| Pin 15 | RC5/SDO — Digital I/O or MSSP SPI data out |
| Pin 16 | RC6/TX/CK — Digital I/O or USART TX/clock |
| Pin 17 | RC7/RX/DT — Digital I/O or USART RX/data |
| Pin 18 | VSS — Digital ground |
| Pin 19 | VDD — Digital supply voltage |
| Pin 20 | RB0/INT0 — Digital I/O or external interrupt 0 |
| Pin 21 | RB1/INT1 — Digital I/O or external interrupt 1 |
| Pin 22 | RB2/INT2 — Digital I/O or external interrupt 2 |
| Pin 23 | RB3/INT3 — Digital I/O or external interrupt 3 |
| Pin 24 | RB4 — Digital I/O (interrupt-on-change) |
| Pin 25 | RB5 — Digital I/O (interrupt-on-change) |
| Pin 26 | RB6/PGC — Digital I/O or ICSP clock (programming/debug) |
| Pin 27 | RB7/PGD — Digital I/O or ICSP data (programming/debug) |
| Pin 28 | AVSS — Analog ground (tie to VSS) |
Typical Applications
PIC18F252T-I/SO is suitable for 7 applications: Industrial Sensor Conditioning, HVAC Thermostat Control, Automotive Body Controller (non-safety), USB-to-UART Bridge, Consumer Appliance UI, Motor Control with PWM Bridges, Data Acquisition Front-End.
Industrial Sensor Conditioning
The PIC18F252T-I/SO's 10-bit 5-channel ADC and 23 digital I/Os make it a fit for industrial sensor-conditioning front-ends that aggregate 4–20 mA or 0–10 V analog signals and drive relays or solid-state outputs. At 10 MIPS the core can run 1 kHz control loops with margin for filtering and HMI scans. Place 100 nF decoupling on each VDD pair, route AVSS to a quiet analog ground island, and use the 256-byte EEPROM to store calibration constants in the field. Compared with a Cortex-M0 part, this design trades raw throughput for simpler IEC 60730 firmware review.
Recommended
HVAC Thermostat Control
The PIC18F252T-I/SO suits 24 V-powered HVAC thermostats where the 4.2–5.5 V regulator output feeds the MCU plus a backlit LCD, keypad scanner, and triac-driven fan relay. The 2 CCP/PWM channels drive the triac optocouplers at 100 Hz to 2 kHz, while the 10-bit ADC reads NTC thermistors through a resistor divider with 0.1 % references for ±0.5 C accuracy. The 32 KB Flash accommodates scheduling, PID, and BLE passthrough stub code, and EEPROM holds setpoints across power cycles. Industrial -40 to +85 C ensures attic and basement operation.
Recommended
Automotive Body Controller (non-safety)
Recommended
USB-to-UART Bridge
The PIC18F252T-I/SO can implement a USB CDC-to-UART bridge when paired with an external USB transceiver or used with a software USB stack on supported device variants. The USART maps directly to RS-232/RS-485 transceivers, while the MSSP can act as an SPI debug port. 32 KB Flash accommodates the CDC stack plus command parser, and the 10 MIPS ensures <1 ms round-trip on typical 115.2 kbaud streams. EEPROM holds baud-rate and VID/PID overrides from factory provisioning.
Recommended
Consumer Appliance UI
In washing machines, dishwashers, and coffee makers, the PIC18F252T-I/SO serves as the HMI controller, scanning 7-segment or TFT displays and reading capacitive or mechanical keypads. The 1536 B SRAM and 256 B EEPROM are sufficient for menu state and last-setting memory, while the 2 PWM channels vary backlight brightness and buzzer tones. The wide 4.2–5.5 V supply tolerance supports directly rectified 5 V rails without additional LDO regulators, lowering BOM cost. Industrial temperature grade covers laundry room humidity excursions.
Recommended
Motor Control with PWM Bridges
The PIC18F252T-I/SO's 2 CCP/PWM modules drive brushed DC motors, small BLDC sensorless fans, or uni-polar steppers at up to 20 kHz switching frequency, with hardware dead-band via firmware sequencing. The 10-bit ADC samples back-EMF or current-sense shunts at tens of kHz to close the speed loop. 32 KB Flash hosts sensorless trapezoidal commutation tables, while EEPROM stores learned parameters between power cycles. Industrial -40 to +85 C suits outdoor fan and pump enclosures.
Recommended
Data Acquisition Front-End
For low-speed multi-channel data loggers, the PIC18F252T-I/SO provides 5 multiplexed 10-bit ADC inputs plus 1 additional comparator-based channel, supporting single-ended or pseudo-differential measurements with software oversampling to reach 12-bit effective resolution. The internal 256-byte EEPROM plus external SPI Flash over MSSP forms a portable logger that streams averaged samples over UART or I2C to a host. At 1536 B SRAM the device accommodates a 256-sample buffer plus TCP/IP lite stub for gateway forwarding.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F252T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F252-I/SO | PIC18F252-E/SO | PIC18F252T-E/SO |
|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-SOIC (300 mil) | 28-SOIC (300 mil) - same | 28-SOIC (300 mil) - same | 28-SOIC (300 mil) - same |
| Program Flash | 32 KB | 32 KB | 32 KB | 32 KB |
| Data SRAM | 1536 B | 1536 B | 1536 B | 1536 B |
| Data EEPROM | 256 B | 256 B | 256 B | 256 B |
| Max CPU Speed | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) | 40 MHz (10 MIPS) |
| Temperature Range | -40 C to +85 C (Industrial) | -40 C to +85 C (Industrial) | -40 C to +125 C (Extended) | -40 C to +125 C (Extended) |
| ADC Resolution | 10-bit, 5 channels | 10-bit, 5 channels | 10-bit, 5 channels | 10-bit, 5 channels |
| Shipping Medium | Tape & Reel | Tube | Tube | Tape & Reel |
Key Differentiators
- Self-programmable Flash with 1536 B SRAM and 256 B EEPROM (vs PIC18F242-I/SO)
- Industrial -40 C to +85 C operating range (vs PIC18F252-E/SO)
- Tape-and-reel packaging for high-volume SMT (vs PIC18F252-I/SO (tube))
Design Notes
Place a 100 nF decoupling capacitor within 5 mm of each VDD/AVDD pin pair and a single 10 uF bulk capacitor at the regulator output. The PIC18F252T-I/SO draws a few mA active and low-uA in sleep; using an LDO such as the MCP1700-3002E (3.3 V) lets you hold RAM content during brief brownouts. Estimated: at 40 MHz the active current is ~15 mA per device datasheet DC characteristics; provide a regulator sized for at least 50 mA to cover in-rush and ISP programming transients.
Route the 28-SOIC land pattern as a 300-mil SOIC footprint with pin 1 dot matching the dot on the SOIC top. Keep the quartz crystal traces to OSC1/OSC2 short (<10 mm) and guard them with a ground ring to minimize EMI. Place the MCLR/VPP pull-up of 10 kOhm near the pin to ease ICSP connection. Estimated: a 2-layer 1.6 mm FR-4 board with a partial ground pour keeps EMI risk low for industrial sensor designs; for USB or switched-power designs a 4-layer stack-up is recommended.
Do not exceed the absolute maximum VDD of 7.0 V (5.5 V recommended operating maximum). The MCLR pin must never be floated; a floating MCLR can latch the device into reset inconsistently under noise. The MSSP module uses the same pins for SPI and I2C - ensure the configuration word disables unused peripherals to free the pins as GPIO. Lastly, always read the PIC18F252 device errata sheet (Microchip DS80322 family) before locking firmware; some silicon revisions have CCP/PWM or ADC-acquisition anomalies.
Compliance Information
RoHS and REACH compliant per Microchip product page. The PIC18F252T-I/SO is not AEC-Q100 qualified; for automotive designs requiring qualification, contact Microchip or select a Q-graded variant.
