PIC18F2520-E/SO - 8-bit 25MHz 32KB Flash MCU | Microchip
MPN: PIC18F2520-E/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.2 | $7.20 |
| 10 | $6.5 | $65.00 |
| 100 | $5.78 | $578.00 |
| 500 | $5.15 | $2,575.00 |
| 1,000 | $4.6 | $4,600.00 |
PIC18F2520-E/SO Overview
A PIC18F microcontroller is an enhanced 8-bit Harvard-architecture RISC core in Microchip's PIC18 family. The PIC18F series adds 16-bit wide instructions and a linear program-memory space on top of the legacy PIC16 architecture, while preserving byte-oriented register access. This particular part targets cost-sensitive embedded control applications that need more program space, more I/O, and richer peripherals than the PIC16F family, without moving to a 16-bit MCU. It sits inside the broader microcontroller hierarchy as: 8-bit MCU -> PIC18 family -> PIC18F2xxx sub-family (28-40-44-pin devices) -> PIC18F2520 specifically.
Key differentiating features include 10-bit analog-to-digital conversion (ADC) with up to 10 input channels, nanoWatt Technology power management for reduced active and sleep currents, an enhanced addressable USART, MSSP serial port supporting SPI and I2C (master/slave), capture/compare/PWM (CCP) modules, and 25 I/O pins with individual pull-up control. The on-chip debug (ICD) capability and self-programmability make field firmware updates possible without an external programmer.
Architecturally, the device uses a 16-bit wide instruction set with an 8-bit data path, a 31-level hardware stack, and a priority-level interrupt controller. nanoWatt Technology adds multiple low-power modes (Run, Idle, Sleep and several oscillator-tunable variants), allowing the designer to trade CPU throughput for current consumption in battery-powered nodes.
Typical applications include industrial control and sensor-interface modules, home-automation and building-control nodes, low-cost motor-control signal chains, USB HID bridges (when paired with the PIC18F2550/4550 variant), embedded data acquisition, and consumer appliances requiring reliable 5 V CMOS logic. The PIC18F2520-E/SO is the 'E' (Extended) temperature grade variant rated for -40 to +125 °C, suitable for industrial environments.
When designing with this part, select decoupling per Microchip's PIC18F2520 datasheet, observe VDD/VSS analog and digital pin separation, and use the MPLAB XC8 compiler with the PIC18 configuration-bit pragma to lock oscillator, watchdog and brown-out behavior at build time.
This page synthesizes distributor pricing, drop-in alternatives and practical design notes for engineers evaluating the PIC18F2520-E/SO in production designs.
Drop-in alternatives for PIC18F2520-E/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 PIC18F2520-E/SO (same form factor and footprint) — differing in Package, Operating Temperature, Timers, ADC, Program Memory (Flash).
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2520-I/SO
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC18F2525-I/SO
✅ Drop-In✓ In Stock
$3.74 / Unit
View Datasheet →PIC18F2420-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F2480-I/SO
✅ Drop-In✓ In Stock
$4.13 / Unit
View Datasheet →PIC18F2523-I/SO
✅ Drop-In ⚠️ Specs Unverified✓ In Stock
$3.12 / Unit
View Datasheet →PIC18F2520-E/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | PIC18 8-bit RISC (Harvard) |
| CPU Speed | 25 MHz (40 MHz oscillator input, up to 10 MIPS) |
| Instruction Cycle | 200 ns (4 clock per instruction) |
| Program Memory (Flash) | 32 KB (16K x 16) |
| RAM | 1.5 KB (1536 bytes) |
| EEPROM | 256 bytes |
| I/O Pins | 25 |
| ADC | 10-bit, up to 10 channels |
| Package | 28-pin SOIC (SO, 7.50 mm body, 1.27 mm pitch) |
| Supply Voltage | 4.2 V to 5.5 V |
| Operating Temperature | -40 °C to +125 °C (E grade) |
| Temperature Grade | Extended (E) |
| Serial Interfaces | EUSART, MSSP (SPI / I2C master & slave) |
| Timers | Timer0/1/2/3 + 2 CCP modules |
| Mounting Type | Surface Mount |
| RoHS Status | Compliant (Pb-free) |
| MSL Level | 1 |
PIC18F2520-E/SO Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master Clear (reset) input / programming voltage / digital input RE3 |
| Pin 2 | RA0/AN0 — PORTA bit 0 / analog input AN0 |
| Pin 3 | RA1/AN1 — PORTA bit 1 / analog input AN1 |
| Pin 4 | RA2/AN2/VREF- — PORTA bit 2 / analog input AN2 / ADC VREF- |
| Pin 5 | RA3/AN3/VREF+ — PORTA bit 3 / analog input AN3 / ADC VREF+ |
| Pin 6 | RA4/T0CKI/C1OUT — PORTA bit 4 / Timer0 clock input / Comparator 1 output |
| Pin 7 | RA5/AN4/SS/HLVDIN/C2OUT — PORTA bit 5 / AN4 / SPI slave select / HLVD input / Comparator 2 output |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKI/RA7 — External oscillator input / digital I/O RA7 |
| Pin 10 | OSC2/CLKO/RA6 — External oscillator output / digital I/O RA6 |
| Pin 11 | RC0/T1OSO/T1CKI — PORTC bit 0 / Timer1 oscillator output / Timer1 clock input |
| Pin 12 | RC1/T1OSI/CCP2 — PORTC bit 1 / Timer1 oscillator input / CCP2 |
| Pin 13 | RC2/CCP1 — PORTC bit 2 / CCP1 |
| 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 / EUSART TX / EUSART clock |
| Pin 18 | RC7/RX/DT — PORTC bit 7 / EUSART RX / EUSART data |
| Pin 19 | VSS — Ground reference |
| Pin 20 | VDD — Positive supply voltage |
| Pin 21 | RB0/INT0/AN10 — PORTB bit 0 / external interrupt 0 / AN10 |
| Pin 22 | RB1/INT1/AN8 — PORTB bit 1 / external interrupt 1 / AN8 |
| Pin 23 | RB2/INT2/AN9 — PORTB bit 2 / external interrupt 2 / AN9 |
| Pin 24 | RB3/AN9/CCP2 — PORTB bit 3 / AN9 / CCP2 alt |
| Pin 25 | RB4/AN11/KBI0 — PORTB bit 4 / AN11 / interrupt-on-change KBI0 |
| Pin 26 | RB5/AN12/KBI1/PGM — PORTB bit 5 / AN12 / KBI1 / LVP program |
| Pin 27 | RB6/KBI2/PGC — PORTB bit 6 / KBI2 / ICD clock |
| Pin 28 | RB7/KBI3/PGD — PORTB bit 7 / KBI3 / ICD data |
Typical Applications
PIC18F2520-E/SO is suitable for 7 applications: Industrial Sensor Interface Module, Home Automation Controller Node, Appliance Control Board, Low-Cost Data Acquisition Front End, Automotive Body Electronics (Non-Safety), Educational and Hobbyist Embedded Platform, Medical Non-Critical Monitoring Accessory.
Industrial Sensor Interface Module
The PIC18F2520-E/SO is a strong fit for industrial 4-20 mA / 0-10 V sensor-interface modules because of its 10-bit ADC with up to 10 input channels, EUSART for Modbus RTU RS-485 links, and -40 °C to +125 °C extended temperature grade. With 32 KB of flash and 1.5 KB of RAM, the MCU has ample headroom for linearization, filtering and Modbus protocol stacks, while the SOIC-28 footprint simplifies hand-soldered prototype rework. The on-chip 256-byte EEPROM stores calibration constants without external memory, and the MSSP peripheral handles I2C sensors alongside the analog channels.
Recommended
Home Automation Controller Node
In home-automation hubs and wall-mounted controllers, the PIC18F2520-E/SO balances cost and capability by providing enough flash (32 KB) for multi-protocol stacks (I2C sensor polling, SPI display drivers, UART to a wireless module) while keeping the BOM short. The MSSP master can drive a 4-digit seven-segment or OLED display, the EUSART links to a Wi-Fi or sub-GHz radio module such as the MRF24J40, and nanoWatt Technology idle/sleep modes keep wall-power consumption low. The 25 I/O pins comfortably accommodate keypad scanning, LED PWM feedback and relay drivers.
Recommended
Appliance Control Board
White-goods and small appliance control boards (coffee machines, dishwashers, washing-machine user-interface boards) commonly use the PIC18F2520-E/SO because the SOIC-28 package is hand-solder-friendly, the 10-bit ADC reads temperature/pressure sensors, and the two CCP modules drive TRIAC phase-control or brushed-motor PWM. The 32 KB flash accommodates graphical menu state machines, while the extended temperature grade withstands under-cabinet heat. The EUSART enables diagnostic logs to a service tool, and nanoWatt Technology idle modes reduce standby power to meet energy-star regulations.
Recommended
Low-Cost Data Acquisition Front End
For multi-channel analog data-logging front ends (battery monitors, environmental stations, lab instruments), the PIC18F2520-E/SO delivers 10 channels of 10-bit ADC at the SOIC-28 footprint, with 32 KB of flash for sample buffering and FFT/averaging code. The MSSP master can stream to an external SPI FRAM (such as FM25L04B) for non-volatile storage, while the EUSART outputs the final dataset to a host PC. The 256-byte on-chip EEPROM preserves calibration across power cycles and the extended temperature grade supports outdoor instrumentation enclosures.
Recommended
Automotive Body Electronics (Non-Safety)
Within non-safety body-electronics modules (HVAC panel controls, seat-position memory, interior lighting controllers), the PIC18F2520-E/SO Extended-grade temperature spec covers the automotive under-dash thermal envelope. The EUSART links to a CAN bridge IC, the CCP modules drive LED dimmers, and the MSSP connects to an I2C keypad/touch controller. While the part is not AEC-Q100 qualified, designers use it extensively in 12 V automotive subsystems where -40 °C to +125 °C operation and 5 V tolerance are required. Note: PIC18F2520 is not AEC-Q100; for safety-critical ECUs select PIC18F46K22-I/P or dsPIC33 variants.
Recommended
Educational and Hobbyist Embedded Platform
The PIC18F2520-E/SO remains a textbook 8-bit reference design in university courses and hobbyist kits because of its compact SOIC-28 footprint, plentiful 32 KB flash for student projects, MPLAB XC8 free-tier toolchain support, and PICKit programmer compatibility. Students can exercise ADC, PWM, I2C, SPI and UART on a single chip, and the SOIC package is easy to hand-solder on a breakout board. The Microchip PIC18F2520 datasheet (document 39631E family) provides extensive register-level documentation, making the device ideal for learning low-level embedded C and assembly.
Recommended
Medical Non-Critical Monitoring Accessory
For non-critical medical accessories such as desktop spirometer data interfaces, physiotherapy timer keypads or laboratory stirrer controllers, the PIC18F2520-E/SO Extended-grade temperature rating and 25 I/O pins support keypad scanning, isolated RS-485 telemetry and LCD/LED display multiplexing. The 32 KB flash fits Modbus firmware plus on-board trend logging, while the 10-bit ADC reads pressure/flow sensors at adequate resolution for non-diagnostic applications. Note: this part is not FDA-cleared; design for IEC 60601 isolation and use external barriers for patient-connected applications.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F2520-E/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2520-I/SO | PIC18F2525-I/SO | PIC18F2420-I/SO | PIC18F2480-I/SO | PIC18F2523-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | SOIC-28 (SO) | SOIC-28 (SO) - same | SOIC-28 (SO) - same | SOIC-28 (SO) - same | SOIC-28 (SO) - same | SOIC-28 (SO) - same |
| Flash Memory | 32 KB | 32 KB | 32 KB | 16 KB (-50%) | 16 KB (-50%) | 32 KB |
| RAM | 1.5 KB | 1.5 KB | 1.5 KB | 768 B (-49%) | 768 B (-49%) | 1.5 KB |
| CPU Speed | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 10-bit | 10-bit | 12-bit (better) |
| Temperature Grade | -40C to +125C (E) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) | -40C to +85C (I) |
| CAN Peripheral | No | No | No | No | Yes (CAN 2.0B) | No |
Key Differentiators
- Extended temperature grade on a production-active SOIC-28 part (vs PIC18F2520-I/SO)
- Newer silicon revision with identical resources (vs PIC18F2525-I/SO)
- 10-bit ADC instead of 12-bit on related part (vs PIC18F2523-I/SO)
- No CAN peripheral but does not require external CAN bridge (vs PIC18F2480-I/SO)
Design Notes
The PIC18F2520-E/SO operates from 4.2 V to 5.5 V on VDD pins 20 and 8; place a 100 nF decoupling capacitor within 5 mm of each VDD pin and a bulk 10 uF tantalum on the supply rail per the Microchip PIC18F2520 datasheet. Enable the on-chip brown-out reset (BOR) configuration bit to ensure a defined startup at VDD < 4.2 V and prevent flash corruption during slow power ramps.
Keep the 25 MHz oscillator traces (OSC1 pin 9, OSC2 pin 10) short and surround them with a ground guard ring to limit EMI. If using a high-speed crystal, place load capacitors within 3 mm of the OSC pins. Route the MCLR line (pin 1) with a 10 kohm pull-up and a 100 nF to ground for in-circuit-debug stability; never leave MCLR floating in production.
Estimated: ADC accuracy at 10 bits requires the analog supply VDD to settle within 1 percent of 5.0 V; a 7805 with 10 uF input/0.1 uF output capacitors is typically adequate. The MSSP I2C pins RC3/RC4 (pins 14/15) require external pull-ups (typically 4.7 kohm to VDD) - the PIC18F2520's I2C drivers are open-drain. Always read the configuration bits via #pragma config in MPLAB XC8 before locking the part, and verify the watchdog timer setting per your application timing budget.
If routing the EUSART to an RS-485 transceiver at 115200 baud or higher, place a 100 ohm series termination at the PIC18F2520 TX pin (RC6, pin 17) and keep the trace impedance near 50 ohm to limit ringing. For MSSP SPI bus speeds above 4 MHz, route SCK (pin 14), SDI (pin 15) and SDO (pin 16) as matched-length traces to avoid data-shift errors; the PIC18F2520 datasheet SSPSTAT register controls SPI timing.
Compliance Information
RoHS and REACH compliant per Microchip PIC18F2520 product page; the 'SO' suffix indicates matte-tin Pb-free finish suitable for 260 °C peak reflow per JEDEC J-STD-020. The part is not AEC-Q100 qualified and therefore not recommended for safety-critical automotive ECUs; for AEC-Q100 designs use PIC18F46K22 or dsPIC33 automotive parts.
