16F84

PIC16F84 Technical Summary

Overview

The PIC16F84 is a high-performance, 8-bit CMOS Flash microcontroller from Microchip Technology. This device features a RISC architecture with only 35 single-word instructions, making it easy to learn and implement in various embedded control applications. The PIC16F84 offers enhanced features over previous generations, including Flash program memory, data EEPROM, and improved I/O capabilities.

With its fully static design, the PIC16F84 can operate across a wide frequency range from DC to 10 MHz, providing flexibility in power consumption versus performance trade-offs. The device is particularly well-suited for applications requiring field reprogrammability due to its Flash memory technology.

Key Features

• High-Performance RISC CPU:
  • Only 35 single-word instructions to learn
  • All instructions are single-cycle (200 ns) except for program branches which take two cycles
  • Operating speed: DC - 10 MHz clock input
  • DC - 200 ns instruction cycle
• Special Microcontroller Features:
  • 1,000 erase/write cycle Flash program memory
  • 1,000,000 erase/write cycle Data EEPROM memory
  • Data EEPROM retention > 40 years
  • In-Circuit Serial Programming (ICSP)
  • Power-on Reset (POR)
  • Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)
  • Watchdog Timer (WDT) with its own on-chip RC oscillator
  • Programmable code protection
  • Power saving SLEEP mode
  • Selectable oscillator options
• Peripheral Features:
  • 13 I/O pins with individual direction control
  • High current sink/source for direct LED drive
  • 8-bit timer/counter with 8-bit prescaler

Applications

The PIC16F84 is suitable for a wide range of embedded control applications including:

• Industrial control systems
• Automotive applications
• Consumer electronics
• Security systems
• Peripheral controllers
• Smart sensors
• Remote transmitters/receivers
• Battery-powered devices
• Home appliances
• Educational and hobbyist projects

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (VDD): -0.3V to +7.5V
• Input Voltage (VIN): -0.3V to (VDD + 0.3V)
• Storage Temperature: -65°C to +150°C
• Operating Temperature: -40°C to +85°C (industrial)

DC Characteristics

• Supply Voltage Range: 2.0V to 5.5V (PIC16F84)
• Operating Current (5V, 4 MHz): 2 mA typical
• Operating Current (3V, 32 kHz): 15 μA typical
• Standby Current (SLEEP mode): 1 μA typical
• Input Low Voltage: 0.15 VDD max
• Input High Voltage: 0.25 VDD min
• I/O Pin Sink/Source Current: 25 mA max per pin

AC Characteristics

• Instruction Cycle Time: 4Tosc (200 ns @ 20 MHz)
• Timer0 Clock Input Frequency: DC to 1/4 of instruction cycle rate
• Reset Pulse Width: 2 μs min
• Watchdog Timer Period: 18 ms typical (with no prescaler)

Memory Organization

Program Memory

The PIC16F84 features 1K x 14 words of Flash program memory, organized as 512 words per page. Program memory is directly or indirectly addressable through the Program Counter (PC).

Data Memory (RAM)

The device includes 68 bytes of general-purpose RAM. The data memory is partitioned into two banks which contain the general-purpose registers and the Special Function Registers (SFRs).

EEPROM Data Memory

The PIC16F84 provides 64 bytes of non-volatile EEPROM data memory that can be read and written during normal operation. This memory has a minimum endurance of 1,000,000 erase/write cycles.

I/O Ports

The PIC16F84 features two I/O ports:

• PORTA: 5-bit bidirectional I/O port
• PORTB: 8-bit bidirectional I/O port

Each port pin can be individually configured as input or output. PORTB features weak internal pull-ups that can be enabled for all input pins. The RA4 pin is open-drain while all other port pins are push-pull.

Timer Module

The Timer0 module is an 8-bit timer/counter with the following features:

• 8-bit timer/counter register (TMR0)
• Readable and writable
• 8-bit software programmable prescaler
• Internal or external clock select
• Interrupt on overflow from FFh to 00h
• Edge select for external clock

Special CPU Features

• Reset: Multiple reset sources including power-on reset, external reset, watchdog timer reset, and brown-out reset
• Oscillator Selection: Four oscillator modes selectable via configuration bits:
  • LP: Low-power crystal
  • XT: Crystal/resonator
  • HS: High-speed crystal/resonator
  • RC: Resistor/capacitor
• Watchdog Timer: Includes its own RC oscillator for reliable operation
• Code Protection: Security bits protect against unauthorized reading of program memory
• Power-saving SLEEP Mode: Reduces power consumption to minimal levels

Package Information

The PIC16F84 is available in the following packages:

• 18-pin PDIP (Plastic Dual In-line Package):
  • Dimensions: 22.86mm x 6.35mm body
  • Lead pitch: 2.54mm
• 18-pin SOIC (Small Outline IC):
  • Dimensions: 11.55mm x 7.50mm body
  • Lead pitch: 1.27mm
• 20-pin SSOP (Shrink Small Outline Package):
  • Dimensions: 7.20mm x 5.30mm body
  • Lead pitch: 0.65mm

Development Support

Microchip provides comprehensive development support for the PIC16F84 including:

• MPLAB Integrated Development Environment (IDE)
• PICkit series programmers/debuggers
• MPLAB ICD in-circuit debuggers
• Third-party