PIC18F4520-I/PT - 8-Bit MCU 40MHz 32KB Flash TQFP-44 | Microchip
MPN: PIC18F4520-I/PT ✓ Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $6.42 | $6.42 |
| 10 | $5.78 | $57.80 |
| 100 | $5.12 | $512.00 |
| 500 | $4.65 | $2,325.00 |
| 1,000 | $4.2 | $4,200.00 |
PIC18F4520-I/PT Overview
An 8-bit microcontroller (MCU) is an integrated circuit that contains a processor core, program memory, data memory, and peripherals on a single chip, executing one instruction per cycle on 8-bit-wide data paths. Within the system hierarchy, the MCU sits at the heart of embedded control systems, ranking below application processors but above simple logic ICs in capability. The PIC18F4xxx family extends Microchip's mid-range PIC architecture with a 16-bit-wide instruction set, enhanced Flash endurance, and nanoWatt technology for low-power design.
Key features of the PIC18F4520 include 10-bit analog-to-digital conversion across multiple channels, nanoWatt power management, capture/compare/PWM (CCP) modules, an enhanced CCP (ECCP) module, and a priority interrupt structure with three programmable external interrupts. Per the family datasheet, the device integrates one 8-bit timer, three 16-bit timers, and a watchdog timer, providing flexible timing resources without external components.
Architecturally, the PIC18F4520 uses a Harvard architecture with separate program and data buses, an Enhanced Flash program memory with high write endurance, and linear addressing via the Phase-Locked Loop (PLL) that multiplies the oscillator input to reach the 40 MHz internal clock. The industrial-grade temperature rating (-40C to +85C, denoted by the -I suffix) suits harsh environments.
Typical applications include industrial automation and control panels, automotive accessories (non-safety), instrumentation and data loggers, and consumer appliance control boards. The 10-bit ADC and CCP/PWM outputs make it well suited to sensor acquisition and motor or LED control.
Design considerations: the 44-TQFP footprint requires careful decoupling of multiple VDD/VSS pairs, and the RB6/RB7 pins double as the In-Circuit Serial Programming (ICSP) clock and data lines - keep programming headers accessible.
This page synthesizes distributor pricing, drop-in alternatives, pinout data, and practical design notes not found in the manufacturer datasheet.
Drop-in alternatives for PIC18F4520-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 PIC18F4520-I/PT (same form factor and footprint) — differing in Operating Temperature, Core, Timers, Package, ADC.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
PIC18LF4520-I/PT
✅ Drop-In✓ In Stock
$5.21 / Unit
View Datasheet →PIC18F4525-I/PT
✅ Drop-In✓ In Stock
$4.18 / Unit
View Datasheet →PIC18F4523-I/PT
✅ Drop-In✓ In Stock
$3.25 / Unit
View Datasheet →PIC18F4580-I/PT
✅ Drop-In📋 Reference alternative (not in catalog)
PIC18F4480-I/PT
✅ Drop-In✓ In Stock
$4.85 / Unit
View Datasheet →PIC18F4520-I/PT Maximum Ratings & Electrical Characteristics
| Core Architecture | 8-bit PIC18 Harvard |
| Maximum Clock Frequency | 40 MHz |
| Program Memory Size | 32 KB (16K x 16) Flash |
| Program Memory Type | Enhanced Flash |
| Package | 44-TQFP (10x10 mm) |
| Mounting Type | Surface Mount |
| ADC Resolution | 10-bit |
| Timers | One 8-bit timer, three 16-bit timers |
| CCP Modules | CCP and enhanced CCP (ECCP) |
| External Interrupts | 3 programmable external interrupts |
| Watchdog Timer | Yes |
| Low Power Technology | nanoWatt Technology |
| Operating Temperature | -40C to +85C (industrial, -I suffix) |
| Pin Count | 44 |
| Programming Interface | ICSP (In-Circuit Serial Programming), supports MPLAB PICkit 5 |
| Series | PIC PIC18F |
PIC18F4520-I/PT Pin Configuration
| Pin 1 | MCLR/VPP/RE3 — Master clear reset / programming voltage / digital input |
| Pin 2 | RA0/AN0 — Port A bit 0 / Analog channel 0 |
| Pin 3 | RA1/AN1 — Port A bit 1 / Analog channel 1 |
| Pin 4 | RA2/AN2/VREF- — Port A bit 2 / Analog channel 2 / ADC negative reference |
| Pin 5 | RA3/AN3/VREF+ — Port A bit 3 / Analog channel 3 / ADC positive reference |
| Pin 6 | RA4/TOCKI/C1OUT — Port A bit 4 / Timer0 clock input / Comparator 1 output |
| Pin 7 | RA5/AN4/SS/HLVDIN/C2OUT — Port A bit 5 / Analog channel 4 / SPI slave select / HLVD input / Comparator 2 output |
| Pin 8 | VSS — Ground reference |
| Pin 9 | OSC1/CLKI/RA7 — Oscillator crystal input / external clock input / Port A bit 7 |
| Pin 10 | OSC2/CLKO/RA6 — Oscillator crystal output / clock output / Port A bit 6 |
| Pin 11 | RC0/T1OSO/T13CKI — Port C bit 0 / Timer1 oscillator output / Timer1/3 external clock |
| Pin 12 | RC1/T1OSI/CCP2 — Port C bit 1 / Timer1 oscillator input / Capture-Compare-PWM 2 |
| Pin 13 | RC2/CCP1 — Port C bit 2 / Capture-Compare-PWM 1 |
| Pin 14 | VDD — Positive power supply |
| Pin 15 | RC3/SCK/SCL — Port C bit 3 / SPI clock / I2C clock |
| Pin 16 | RD0/PSP0 — Port D bit 0 / Parallel slave port bit 0 |
| Pin 17 | RD1/PSP1 — Port D bit 1 / Parallel slave port bit 1 |
| Pin 18 | RD2/PSP2 — Port D bit 2 / Parallel slave port bit 2 |
| Pin 19 | RD3/PSP3 — Port D bit 3 / Parallel slave port bit 3 |
| Pin 20 | RC4/SDI/SDA — Port C bit 4 / SPI data in / I2C data |
| Pin 21 | RC5/SDO — Port C bit 5 / SPI data out |
| Pin 22 | RC6/TX/CK — Port C bit 6 / USART transmit / SPI clock |
| Pin 23 | RC7/RX/DT — Port C bit 7 / USART receive / data |
| Pin 24 | RD4/PSP4 — Port D bit 4 / Parallel slave port bit 4 |
| Pin 25 | RD5/PSP5 — Port D bit 5 / Parallel slave port bit 5 |
| Pin 26 | RD6/PSP6 — Port D bit 6 / Parallel slave port bit 6 |
| Pin 27 | RD7/PSP7 — Port D bit 7 / Parallel slave port bit 7 |
| Pin 28 | VSS — Ground reference |
| Pin 29 | VDD — Positive power supply |
| Pin 30 | RB0/INT0 — Port B bit 0 / External interrupt 0 |
| Pin 31 | RB1/INT1 — Port B bit 1 / External interrupt 1 |
| Pin 32 | RB2/INT2 — Port B bit 2 / External interrupt 2 |
| Pin 33 | RB3/CCP2 — Port B bit 3 / Capture-Compare-PWM 2 (alternate) |
| Pin 34 | RB4 — Port B bit 4 / interrupt-on-change |
| Pin 35 | RB5/PGM — Port B bit 5 / low-voltage programming pin |
| Pin 36 | RB6/PGC — Port B bit 6 / ICSP programming clock |
| Pin 37 | RB7/PGD — Port B bit 7 / ICSP programming data |
| Pin 38 | RE0/RD/AN5 — Port E bit 0 / PSP read strobe / Analog channel 5 |
| Pin 39 | RE1/WR/AN6 — Port E bit 1 / PSP write strobe / Analog channel 6 |
| Pin 40 | RE2/CS/AN7 — Port E bit 2 / PSP chip select / Analog channel 7 |
| Pin 41 | AVDD — Analog positive supply (for ADC) |
| Pin 42 | AVSS — Analog ground (for ADC) |
| Pin 43 | VSS — Ground reference |
| Pin 44 | VDD — Positive power supply |
Typical Applications
PIC18F4520-I/PT is suitable for 6 applications: Industrial Automation and Control, Instrumentation and Data Logging, Motor and LED PWM Control, Consumer Appliance Control, Automotive Accessories (Non-Safety), Embedded Learning and Prototyping.
Industrial Automation and Control
The PIC18F4520-I/PT fits industrial control boards because its 40 MHz core, three 16-bit timers, and CCP/ECCP modules handle timing-critical sequencing, while the 10-bit ADC digitizes up to 13 analog sensor channels such as potentiometers, current shunts, and temperature sensors. In a PLC-style I/O card it reads analog inputs, drives relay outputs via the parallel slave port or PORTD, and communicates over UART (RC6/RX, RC7/TX) to supervisory systems. The -I grade (-40C to +85C) covers control-cabinet environments. Design with watchdog enabled and ceramic decoupling at each of the multiple VDD/VSS pin pairs to survive noisy switch-mode loads.
Recommended
Instrumentation and Data Logging
For data loggers and bench instruments, the PIC18F4520-I/PT combines a 10-bit ADC with nanoWatt technology so the system can sleep between samples and wake on external interrupt (INT0/INT1/INT2 on RB0-RB2). A typical design samples analog channels at 10-bit resolution, time-stamps them with Timer1 (which can run from a 32.768 kHz watch crystal on T1OSO/T1OSI), and stores results in external EEPROM over the RC3/SCL, RC4/SDA I2C lines. The ECCP module can gate a precision excitation pulse for sensor ratiometric measurements. Current during Run depends on clock; verify datasheet figures for your voltage and frequency combination before battery sizing.
Recommended
Motor and LED PWM Control
The ECCP module of the PIC18F4520-I/PT generates half-bridge and full-bridge PWM with programmable dead-band control, making it appropriate for DC and stepper motor drives and for high-power LED dimming. PWM resolution scales with the timer clock - at 40 MHz the module supports up to 10-bit PWM at reduced frequency or 8-bit PWM at higher frequency, per the family datasheet. The 10-bit ADC closes the loop by reading motor current via a shunt or LED current feedback. Use RC2/CCP1 or RB3/CCP2 as the PWM output, and pair with an external gate driver rather than driving MOSFET gates directly from the MCU pins.
Recommended
Consumer Appliance Control
Appliance control boards (rice cookers, air conditioners, coffee machines) benefit from the PIC18F4520-I/PT's low system cost, 32 KB of Flash holding user-interface plus control firmware, and RB0-RB7 with weak pull-ups for a membrane-key matrix. The nanoWatt technology keeps standby consumption low for always-plugged appliances, and the internal PLL lets a low-cost crystal generate the 40 MHz operating clock. The 10-bit ADC reads NTC thermistors for temperature closed-loop control while CCP outputs drive triacs or relays via zero-cross timing. The 44-TQFP (10x10 mm) footprint keeps the PCB compact for control-panel housings.
Recommended
Automotive Accessories (Non-Safety)
For non-safety automotive accessories such as lighting controllers, seat-memory modules, and telematics add-ons, the PIC18F4520-I/PT's industrial -40C to +85C range suits cabin and under-dash zones. The 10-bit ADC reads battery-sense and potentiometer inputs, while the ECCP module generates lamp PWM and the UART (RC6/RC7) links to telematics or K-line interfaces. Design considerations include load-dump transient protection upstream of the regulator, a brown-out configuration on reset, and watchdog supervision. For CAN-enabled accessories in the same footprint, the drop-in PIC18F4580-I/PT variant adds an ECAN controller without PCB rework, simplifying platform sharing across vehicle lines.
Recommended
Embedded Learning and Prototyping
The PIC18F4520-I/PT remains a popular teaching MCU in embedded-systems courses because it exposes classic peripherals - UART, I2C/SPI, CCP/PWM, a multi-channel 10-bit ADC, and external interrupts - on a single well-documented 8-bit core. Prototyping uses Microchip's MPLAB X IDE with a PICkit 5 debugger connected to a 5-pin ICSP header on RB6/RB7/MCLR, allowing in-circuit flashing of the 32 KB Flash across thousands of erase cycles. DIP adapter boards convert the 44-TQFP footprint for breadboard use. Students learn Harvard architecture, interrupt prioritization, and nanoWatt power modes with the same tools used in production environments.
Recommended
Recommended Products Summary
Engineering reference data for PIC18F4520-I/PT — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | PIC18LF4520-I/PT | PIC18F4525-I/PT | PIC18F4523-I/PT | PIC18F4580-I/PT | PIC18F4480-I/PT |
|---|---|---|---|---|---|---|
| Package | 44-TQFP (10x10 mm) | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same | 44-TQFP (10x10 mm) - same |
| Brand | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology | Microchip Technology |
| Program Memory (Flash) | 32 KB (16K x 16) | 32 KB (16K x 16) | 48 KB (24K x 16) | 64 KB (32K x 16) | 32 KB (16K x 16) | 16 KB (8K x 16) |
| Max Clock Frequency | 40 MHz | 40 MHz (derates at low VDD) | 40 MHz | 40 MHz | 40 MHz | 40 MHz |
| ADC Resolution | 10-bit | 10-bit | 10-bit | 12-bit | 10-bit | 10-bit |
| CAN Peripheral | No | No | No | No | Yes (ECAN) | Yes (CAN 2.0B) |
| Low-Voltage Option | No (standard 5 V class) | Yes (LF, ~2.0 V min) | No | No | No | No |
| ICSP Programming | Yes (RB6/RB7, MPLAB PICkit 5) | Yes (same pins) | Yes (same pins) | Yes (same pins) | Yes (same pins) | Yes (same pins) |
| Operating Temperature | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C | -40C to +85C |
Key Differentiators
- Low-voltage operation for battery and mixed-rail designs (vs PIC18LF4520-I/PT)
- Balanced 32 KB Flash headroom (vs PIC18F4480-I/PT)
- Cost-optimized for non-networked control (vs PIC18F4580-I/PT)
- Simple 10-bit ADC keeps cost low (vs PIC18F4523-I/PT)
Design Notes
The TQFP-44 provides four separate VDD/VSS pin pairs plus dedicated AVDD/AVSS pins (41/42) for the ADC. Decouple each VDD pin with a 100 nF ceramic capacitor placed within 2-3 mm of the pin, and add one bulk 4.7-10 uF capacitor near the supply entry. Connect AVDD to VDD through an RC or ferrite filter and tie AVSS to a quiet analog ground island - this directly improves ADC noise performance on the 10-bit converter, where even 1 LSB corresponds to about 4.9 mV at a 5 V reference.
RB6 (PGC) and RB7 (PGD) double as the ICSP programming clock and data lines. If your application drives these pins, ensure the external circuitry does not fight the programmer - series resistors (typically 470 ohm-1 kohm) on both lines isolate application loads while leaving ICSP functional. Also reserve pin 1 (MCLR/VPP) for the programming voltage: never clamp it with a strong pull-up to VDD unless you have disabled MCLR in configuration fuses and accept low-voltage programming limitations.
nanoWatt Technology on the PIC18F4520 enables multiple sleep and idle modes. For battery designs, run the clock from the internal oscillator or a low-frequency Timer1 crystal during sleep and switch to the PLL-driven 40 MHz clock only when computation is required. Estimated: at a typical 5 V system, dynamic current scales roughly linearly with frequency, so sleeping between tasks can reduce average current by an order of magnitude versus running continuously - confirm exact figures against the datasheet current-versus-frequency tables for your voltage.
When using the parallel slave port (RD0-RD7 with RE0-RE2 strobes) to interface with a host processor, keep the bus traces short (<10 cm) and consider series termination if the host drives fast edges. Unused PORTB pins should be configured with weak internal pull-ups or driven outputs to avoid floating-input oscillation, which increases supply noise and can upset the interrupt-on-change logic.
Compliance Information
Compliance status not stated in the provided verified web data. Microchip standard production parts are typically RoHS-compliant, but verify on the official Microchip product page before specification.