Here's a Description of its key Features:

8-Bit RISC Architecture: The PIC18F4520 follows an 8-bit Reduced Instruction Set Computing (RISC) architecture, providing a powerful and efficient instruction set.

32 KB Flash Memory: This memory is used for storing the program code. It is non-volatile, allowing the retention of the program even when power is turned off.

1536 Bytes RAM: Random Access Memory (RAM) is used for temporary data storage during program execution.

256 Bytes EEPROM: Electrically Erasable Programmable Read-Only Memory provides non-volatile storage for user data.

Clock Speed: The microcontroller supports a wide range of clock speeds, including a High-Speed Internal Oscillator (up to 8 MHz) and an External Clock up to 40 MHz.

On-Chip Oscillator and Clock Circuitry: It includes an on-chip oscillator and clock circuitry, reducing the need for external components for clock generation.

Three 16-bit Timer/Counters: These timers/counters are versatile and can be used for tasks such as time measurement, pulse width modulation (PWM), and event counting.

Capture/Compare/PWM Modules: These modules provide additional capabilities for capturing, comparing, and generating PWM signals.

USART, MSSP (I2C/SPI), and EUSART: Serial communication modules for various communication protocols.

10-bit Analog-to-Digital Converter (ADC): Allows the microcontroller to interface with analog sensors and signals.

Communication Ports: The microcontroller supports various communication protocols, making it suitable for applications that require data transfer.

Parallel Master Port (PMP): The PMP facilitates communication with external memory devices.

Programming and Flash Memory Protection: The PIC18F4520 supports in-system programming, allowing the user to program the device after it has been placed in the target system. It features Flash memory protection options.

Low Power Consumption: The microcontroller is designed for low power consumption, making it suitable for battery-operated devices.

Operating Voltage: The typical operating voltage is 2.0V to 5.5V.

Package Type: The PIC18F4520 comes in a Dual In-line Package (DIP) with 40 pins, facilitating easy integration into breadboards and circuit designs.