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

• PIC18F2455 • PIC18LF2455
• PIC18F2550 • PIC18LF2550
• PIC18F4455 • PIC18LF4455
• PIC18F4550 • PIC18LF4550

This family of devices offers the advantages of all PIC18 microcontrollers – namely, high computational performance at an economical price – with the addition of high-endurance, Enhanced Flash program memory. In addition to these features, the PIC18F2455/2550/4455/4550 family introduces design enhancements that make these microcontrollers a logical choice for many high-performance, power sensitive applications.

Universal Serial Bus Features:
• USB V2.0 Compliant
• Low Speed (1.5 Mb/s) and Full Speed (12 Mb/s)
• Supports Control, Interrupt, Isochronous and Bulk Transfers
• Supports up to 32 Endpoints (16 bidirectional)
• 1 Kbyte Dual Access RAM for USB
• On-Chip USB Transceiver with On-Chip Voltage Regulator
• Interface for Off-Chip USB Transceiver
• Streaming Parallel Port (SPP) for USB streaming transfers (40/44-pin devices only)

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 Currents Down to 0.1 μA Typical
• Timer1 Oscillator: 1.1 μA Typical, 32 kHz, 2V
• Watchdog Timer: 2.1 μA Typical
• Two-Speed Oscillator Start-up

Flexible Oscillator Structure:
• Four Crystal modes, including High-Precision PLL for USB
• Two External Clock modes, Up to 48 MHz
• Internal Oscillator Block:
  - 8 user-selectable frequencies, from 31 kHz to 8 MHz
  - User-tunable to compensate for frequency drift
• Secondary Oscillator using Timer1 @ 32 kHz
• Dual Oscillator Options allow Microcontroller and USB module to Run at Different Clock Speeds
• Fail-Safe Clock Monitor:
  - Allows for safe shutdown if any clock stops

Peripheral Highlights:
• High-Current Sink/Source: 25 mA/25 mA
• Three External Interrupts
• Four Timer modules (Timer0 to Timer3)
• Up to 2 Capture/Compare/PWM (CCP) modules:
  - Capture is 16-bit, max. resolution 5.2 ns (TCY/16)
  - Compare is 16-bit, max. resolution 83.3 ns (TCY)
  - PWM output: PWM resolution is 1 to 10-bit
• Enhanced Capture/Compare/PWM (ECCP) module:
  - Multiple output modes
  - Selectable polarity
  - Programmable dead time
  - Auto-shutdown and auto-restart
• Enhanced USART module:
  - LIN bus support
• Master Synchronous Serial Port (MSSP) module Supporting 3-Wire SPI (all 4 modes) and I2C™ Master and Slave modes
• 10-Bit, Up to 13-Channel Analog-to-Digital Converter (A/D) module with Programmable Acquisition Time
• Dual Analog Comparators with Input Multiplexing