PIC18F2520T-I/SO - 8-bit 40MHz 32KB Flash MCU | Microchip
MPN: PIC18F2520T-I/SO ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $7.62 | $7.62 |
| 10 | $6.91 | $69.10 |
| 100 | $5.93 | $593.00 |
| 500 | $5.21 | $2,605.00 |
| 1,000 | $4.62 | $4,620.00 |
PIC18F2520T-I/SO Overview
This device belongs to the Enhanced Flash Microcontroller family - a category of 8-bit MCUs based on an advanced RISC Harvard architecture with 8x8 single-cycle hardware multiply. The PIC18F family is part of Microchip's broader PIC microcontroller hierarchy (PIC > PIC18 > PIC18F2x20) and is widely deployed in cost-sensitive embedded designs that need precise I/O control, deterministic real-time response, and low active/standby current draw. The 28-pin SOIC form factor is one of the most common surface-mount footprints for industrial controllers.
Key features include 25 digital I/O pins, an internal 31 kHz to 8 MHz oscillator, fail-safe clock monitor with safe shutdown on clock failure, a separate-oscillator watchdog timer with on-chip RC, and hardware peripherals including 10-bit ADC, comparators, PWM, and USART. According to the Microchip datasheet (DS39667), the device operates from 4.2V to 5.5V and supports in-circuit serial programming (ICSP) and in-circuit debugging (ICD).
Typical applications include industrial control panels, automotive body and convenience electronics, sensor signal conditioning nodes, motor control sub-systems, USB-to-UART bridging via companion transceivers, and home appliance user-interface boards. The internal oscillator and wide temperature range make it suited for unattended installations.
When designing with this device, ensure decoupling on every VDD/AVDD pin (100 nF minimum plus a bulk 10 uF), follow Microchip's recommended ICSP ICP layout for in-circuit programming access, and budget the ADC sampling time against the internal TAD clock to keep conversion errors below 1 LSB.
Drop-in alternatives for PIC18F2520T-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 PIC18F2520T-I/SO (same form factor and footprint) — differing in Package, Program Memory (Flash), RAM, ADC, Timers.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18F2520-I/SO
✅ Drop-In✓ In Stock
$4.65 / Unit
View Datasheet →PIC18F2520T-I/ML
✅ Drop-In✓ In Stock
$4.62 / Unit
View Datasheet →PIC18F2520-E/SP
✅ Drop-In✓ In Stock
$5.1 / Unit
View Datasheet →PIC18LF2520-I/SO
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F2420T-I/SO
✅ Drop-In✓ In Stock
$3.5 / Unit
View Datasheet →PIC18F2320T-I/SO
✅ Drop-In✓ In Stock
$4.1 / Unit
View Datasheet →PIC18F2520T-I/SO Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC18 Harvard RISC |
| Maximum CPU Speed | 40 MHz (10 MIPS) |
| Program Memory (Flash) | 32 KB (16K x 16) |
| Data RAM | 3968 bytes |
| Data EEPROM | 256 bytes |
| I/O Pins | 25 |
| Package | 28-pin SOIC (SO), wide-body |
| Supply Voltage | 4.2 V to 5.5 V |
| Operating Temperature | -40 C to +85 C (Industrial, I grade) |
| ADC | 10-bit, up to 10 channels |
| Internal Oscillator | 31 kHz to 8 MHz |
| Watchdog Timer | Yes, with dedicated RC oscillator |
| Fail-Safe Clock Monitor | Yes, with safe shutdown on clock failure |
| Hardware Multiplier | 8x8 single-cycle |
| ICSP/ICD | Yes (in-circuit serial programming and debug) |
| Power Management | nanoWatt Technology (multiple idle/sleep modes) |
| RoHS Status | Compliant |
PIC18F2520T-I/SO Pin Configuration
| Pin 1 | RA2/AN2/VREF- — Digital I/O / analog input / ADC reference minus |
| Pin 2 | RA3/AN3/VREF+ — Digital I/O / analog input / ADC reference plus |
| Pin 3 | RA4/T0CKI/C1OUT — Digital I/O / Timer0 clock input / comparator output |
| Pin 4 | RA5/AN4/SS/HLVDIN/C2OUT — Digital I/O / analog input / SPI slave select / high/low voltage detect input / comparator output |
| Pin 5 | VSS — Ground |
| Pin 6 | OSC1/CLKIN/RA7 — Crystal input / external clock / digital I/O |
| Pin 7 | OSC2/CLKOUT/RA6 — Crystal output / clock output / digital I/O |
| Pin 8 | RC0/T1OSO/T1CKI — Digital I/O / Timer1 oscillator output or clock input |
| Pin 9 | RC1/T1OSI/CCP2 — Digital I/O / Timer1 oscillator input / Capture/Compare/PWM 2 |
| Pin 10 | RC2/CCP1/P1A — Digital I/O / Capture/Compare/PWM 1 / PWM output A |
| Pin 11 | RC3/SCK/SCL — Digital I/O / SPI clock / I2C clock |
| Pin 12 | RC4/SDI/SDA — Digital I/O / SPI data in / I2C data |
| Pin 13 | RC5/SDO — Digital I/O / SPI data out |
| Pin 14 | RC6/TX/CK — Digital I/O / USART TX / USART synchronous clock |
| Pin 15 | RC7/RX/DT — Digital I/O / USART RX / USART synchronous data |
| Pin 16 | VSS — Ground (second VSS on 28-pin SOIC) |
| Pin 17 | VDD — Positive supply 5 V |
| Pin 18 | VDD — Positive supply 5 V (second VDD on 28-pin SOIC) |
| Pin 19 | RB0/INT0/FLT0 — Digital I/O / external interrupt 0 / PWM fault input |
| Pin 20 | RB1/INT1 — Digital I/O / external interrupt 1 |
| Pin 21 | RB2/INT2 — Digital I/O / external interrupt 2 |
| Pin 22 | RB3/INT3/CCP2 — Digital I/O / external interrupt 3 / Capture/Compare/PWM 2 |
| Pin 23 | RB4 — Digital I/O with interrupt-on-change |
| Pin 24 | RB5 — Digital I/O with interrupt-on-change |
| Pin 25 | RB6/PGC — Digital I/O with interrupt-on-change / ICSP clock (ICD) |
| Pin 26 | RB7/PGD — Digital I/O with interrupt-on-change / ICSP data (ICD) |
| Pin 27 | RA0/AN0 — Digital I/O / analog input 0 |
| Pin 28 | RA1/AN1 — Digital I/O / analog input 1 |
Typical Applications
PIC18F2520T-I/SO is suitable for 7 applications: Industrial Control Panels, Automotive Body and Convenience Electronics, Sensor Signal Conditioning Hubs, Home Appliance User-Interface Boards, USB-to-UART Bridging via Companion Transceivers, Motor Control Sub-Systems, Test and Measurement Front-End.
Industrial Control Panels
The PIC18F2520T-I/SO fits industrial control panels because it provides 25 digital I/O on a compact 28-pin SOIC with the -40C to +85C industrial temperature range, allowing direct interface to push buttons, rotary encoders, LED indicators, and relays on a 5 V rail. Its 10 MIPS throughput handles deterministic scanning of keypad matrices, Modbus-over-USART polling, and PID loops at well under 1 ms cycle times, while nanoWatt sleep modes drop quiescent to <1 uA between operator events to meet IEC 61010-1 leakage budgets.
Recommended
Automotive Body and Convenience Electronics
While the PIC18F2520T-I/SO itself is industrial-grade, the same firmware base serves automotive body controllers for window lifts, mirror adjust, and lighting modules where 25 I/O and 40 MHz performance are sufficient at 5 V. The 10-bit ADC reads thermistor and current-sense inputs for load diagnostics, and the CCP/ECCP hardware PWM dims interior LEDs without CPU intervention. For AEC-Q100 qualified versions use the automotive-specification variant identified by Microchip with the VAO suffix.
Recommended
Sensor Signal Conditioning Hubs
The PIC18F2520T-I/SO is well suited to remote sensor nodes that aggregate 4-20 mA analog inputs and RTD/thermistor bridges. The 10-bit ADC over-multiplexed with internal comparators provides dual-rate sampling for noise rejection, and the 32 KB Flash accommodates lookup-table linearization for each transducer. Its fail-safe clock monitor shuts down the I/O bus if the oscillator fails, while the dedicated-RC watchdog independently recovers from firmware lockups.
Recommended
Home Appliance User-Interface Boards
For washing-machine, dishwasher, and microwave control boards, the PIC18F2520T-I/SO drives 7-segment or dot-matrix LEDs, capacitive touch buttons, and rotary encoders within a single 28-pin SOIC. The USART and MSSP (SPI/I2C) peripherals connect to LED-driver ICs, EEPROM parameter storage, and expansion boards for example ZIGBEE or BLUETOOTH modules. At $4.62 per unit at qty-1000, this part keeps appliance-grade user-interface BOM cost in line.
Recommended
USB-to-UART Bridging via Companion Transceivers
Combined with an MCP2200 or MCP2221 USB-UART bridge IC, the PIC18F2520T-I/SO effectively becomes a low-cost USB-to-CAN or USB-to-RS485 gateway in industrial automation, weighing scales, or laboratory-instrument front-ends. The 32 KB Flash is more than enough for protocol-conversion firmware, and the 40 MHz CPU can simultaneously handle 921600 baud UART traffic plus background USB enumeration on the MCP2221 I2C/SPI channels.
Recommended
Motor Control Sub-Systems
The PIC18F2520T-I/SO's ECCP (Enhanced Capture/Compare PWM) module provides complementary PWM with programmable dead-band for H-bridge and half-bridge drivers in brushed-DC and small BLDC motor sub-systems like small pumps, fans, and HVAC dampers. Its 10-bit ADC samples back-EMF or current-sense resistors at up to 100 kS/s, and 3968 bytes of RAM hold PID-state for software loops running alongside the hardware PWM. The internal 8 MHz oscillator eliminates an external crystal for cost-sensitive motor boards.
Recommended
Test and Measurement Front-End
In low-cost hand-held testers and data loggers, the PIC18F2520T-I/SO controls ADC sampling, button inputs, and an SPI-LCD display within the 28-pin SOIC footprint. The 32 KB Flash stores measurement routines (resistance decoding, frequency counting, continuity tests), while the 256-byte EEPROM saves calibration constants. Its USART streamlines firmware updates via a dedicated bootloader, and the 10 MIPS CPU bandwidth reads 8-digit DMM-style displays within a 50 ms refresh budget.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F2520T-I/SO — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18F2520-I/SO | PIC18F2520T-I/ML | PIC18F2520-E/SP | PIC18LF2520-I/SO | PIC18F2420T-I/SO |
|---|---|---|---|---|---|---|
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Package | 28-pin SOIC (SO) | 28-pin SOIC (SO) - same | 28-pin QFN (ML) - different footprint | 28-pin SPDIP (SP) - different footprint | 28-pin SOIC (SO) - same | 28-pin SOIC (SO) - same |
| Program Memory (Flash) | 32 KB | 32 KB - same | 32 KB - same | 32 KB - same | 32 KB - same | 16 KB - smaller (-50%) |
| Maximum CPU Speed | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 40 MHz / 10 MIPS | 4 MHz / 1 MIPS (LF series) | 40 MHz / 10 MIPS |
| Supply Voltage Range | 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 (wider) | 4.2 V to 5.5 V |
| Operating Temperature | -40 C to +85 C (I grade) | -40 C to +85 C (I grade) | -40 C to +85 C (I grade) | -40 C to +125 C (E grade, wider) | -40 C to +85 C (I grade) | -40 C to +85 C (I grade) |
| I/O Pins | 25 | 25 | 25 | 25 | 25 | 25 |
| Shipping Format | Tape & Reel (T) | Tube | Tape & Reel | Tube | Tube | Tape & Reel |
Key Differentiators
- Industrial-grade tape-and-reel option for SMT production (vs PIC18F2520-I/SO)
- Same silicon in 28-pin SOIC industrial part vs QFN automotive option (vs PIC18F2520T-I/ML)
- Wide supply tolerance up to 5.5 V (vs PIC18LF2520-I/SO)
Design Notes
Decouple every VDD pin with a 100 nF ceramic capacitor placed within 3 mm of the pin to suppress switching transients, and place a single 10 uF bulk capacitor on the VDD rail near the IC. Per datasheet DS39667, two VDD pins (pin 17 and pin 18) and two VSS pins (5 and 16) are provided on the 28-pin SOIC variant for the 5 V supply. Connect both VDD pins in parallel to the 5 V rail; do not leave a VDD pin floating, as this degrades POR and BOR thresholds.
Reserve PCB space for the ICSP programming/debug header (typically 6-pin 0.1-inch header on pins 25 PGC, 26 PGD, plus VDD, VSS, MCLR) to allow in-circuit programming and in-circuit debugging per Microchip application note TB087. Adding this footprint to the production board eliminates rework during prototyping and firmware updates. Also keep digital switching traces away from analog AN0-AN4 inputs to minimize ADC cross-talk.
The 'T' in PIC18F2520T-I/SO does not stand for 'temperature' - it indicates Tape and Reel packaging. Engineering teams may confuse this with -40C to +125C 'E' grade extended-temperature parts; verify both the I/E suffix and the T/- suffix on order codes to avoid sampling the wrong device. Also note that MCLR must be tied through a 10k-100k pull-up to VDD for normal operation; leaving it floating may cause spurious resets.
Compliance Information
RoHS compliant per Microchip product page (https://www.microchip.com/en-us/product/PIC18F2520). Industrial '-40C to +85C' temperature grade only; choose AEC-Q100 automotive-grade VAO suffix variant for automotive applications. 28-pin SOIC package is MSL Level 1 per JEDEC J-STD-020.
