DEVICE OVERVIEW
This document contains device specific information for the following devices:

• PIC18F2420 • PIC18LF2420
• PIC18F2520 • PIC18LF2520
• PIC18F4420 • PIC18LF4420
• PIC18F4520 • PIC18LF4520

This family offers the advantages of all PIC18 micro controllers – namely, high computational performance at an economical price – with the addition of high endurance, Enhanced Flash program memory. On top of these features, the PIC18F2420/2520/4420/4520 family introduces design enhancements that make these microcontrollers a logical choice for many high performance, power sensitive applications.

Power Managed Modes:
• Run: CPU on, peripherals on
• Idle: CPU off, peripherals on
• Sleep: CPU off, peripherals off
• Idle mode currents down to 5.8 µA typical
• Sleep mode current down to 0.1 µA typical
• Timer1 Oscillator: 1.8 µA, 32 kHz, 2V
• Watchdog Timer: 2.1 µA
• Two-Speed Oscillator Start-up

Peripheral Highlights:
• High-current sink/source 25 mA/25 mA
• Three programmable external interrupts
• Four input change interrupts
• Up to 2 Capture/Compare/PWM (CCP) modules, one with Auto-Shutdown (28-pin devices)
• Enhanced Capture/Compare/PWM (ECCP) module (40/44-pin devices only):
  - One, two or four PWM outputs
  - Selectable polarity
  - Programmable dead time
  - Auto-Shutdown and Auto-Restart
• Master Synchronous Serial Port (MSSP) module
supporting 3-wire SPI™ (all 4 modes) and I2C™ Master and Slave Modes
• Enhanced Addressable USART module:
  - Supports RS-485, RS-232 and LIN 1.2
  - RS-232 operation using internal oscillator block (no external crystal required)
  - Auto-Wake-up on Start bit
  - Auto-Baud Detect
• 10-bit, up to 13-channel Analog-to-Digital Converter module (A/D):
 - Auto-acquisition capability
 - Conversion available during Sleep
• Dual analog comparators with input multiplexing)

Flexible Oscillator Structure:
• Four Crystal modes, up to 40 MHz
• 4X Phase Lock Loop (available for crystal and internal oscillators)
• Two External RC modes, up to 4 MHz
• Two External Clock modes, up to 40 MHz
• Internal oscillator block:
  - 8 user selectable frequencies, from 31 kHz to 8 MHz
  - Provides a complete range of clock speeds from 31 kHz to 32 MHz when used with PLL
  - User tunable to compensate for frequency drift
• Secondary oscillator using Timer1 @ 32 kHz
• Fail-Safe Clock Monitor:
  - Allows for safe shutdown if peripheral clock stops

Special Microcontroller Features:
• C compiler optimized architecture:
- Optional extended instruction set designed to optimize re-entrant code
• 100,000 erase/write cycle Enhanced Flash program memory typical
• 1,000,000 erase/write cycle Data EEPROM memory typical
• Flash/Data EEPROM Retention: 100 years typical
• Self-programmable under software control
• Priority levels for interrupts
• 8 x 8 Single-Cycle Hardware Multiplier
• Extended Watchdog Timer (WDT):
- Programmable period from 4 ms to 131s
• Single-supply 5V In-Circuit Serial Programming™ (ICSP™) via two pins
• In-Circuit Debug (ICD) via two pins
• Wide operating voltage range: 2.0V to 5.5V
• Programmable 16-level High/Low-Voltage

Detection (HLVD) module:
  - Supports interrupt on High/Low-Voltage Detection
• Programmable Brown-out Reset (BOR
  - With software enable option