HC705XX7

HC705XX7 Technical Summary

Overview

The HC705XX7 is a member of the MC68HC05 microcontroller family, featuring an 8-bit architecture with integrated memory and I/O capabilities. This component is designed for low-cost embedded applications requiring reliable performance and flexible interfacing options.

Key Features

• 8-bit HC05 CPU core
• On-chip memory including RAM and EPROM/OTPROM
• Multiple operating modes including user and special modes
• Integrated analog subsystem with A/D conversion capabilities
• Multiple timer modules including core timer and programmable timer
• Parallel I/O ports with configurable direction control
• Simple Serial Interface (SIOP) for communication
• Low-power operating modes (Stop, Wait, Halt)
• Multiple reset sources including power-on, external, and watchdog

Applications

• Consumer electronics
• Industrial control systems
• Automotive electronics
• Home appliances
• Embedded sensor systems

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (VDD): -0.3V to +7.0V
• Input Voltage: -0.3V to VDD + 0.3V
• Operating Temperature Range: -40°C to +85°C
• Storage Temperature Range: -55°C to +150°C

Recommended Operating Conditions

• Supply Voltage (VDD): 2.7V to 5.5V
• Operating Temperature: -40°C to +85°C
• Clock Frequency: Up to 4MHz (dependent on VDD)

Power Consumption

• Active Mode (5V @ 4MHz): 10mA typical
• Wait Mode (5V): 2mA typical
• Stop Mode (5V): 100μA typical

Package Information

• 20-pin Plastic Dual In-Line Package (PDIP)
• 20-pin Small Outline Integrated Circuit (SOIC)
• 28-pin PDIP (for expanded I/O versions)
• 28-pin SOIC (for expanded I/O versions)

Detailed Functional Description

Memory Organization

The HC705XX7 features a unified memory architecture with:

• Up to 2KB of EPROM/OTPROM for program storage
• 128 bytes of RAM for data storage
• Memory-mapped I/O registers
• Interrupt vector table in high memory

CPU Core

The 8-bit CPU features:

• Accumulator (A) register
• Index register (X)
• Stack pointer (SP)
• Program counter (PC)
• Condition code register (CCR)
• 62 basic instructions
• Multiple addressing modes

I/O Ports

The device includes multiple parallel I/O ports:

• Port A: 6-bit general purpose I/O
• Port B: 8-bit multifunction I/O (some pins have alternate functions)
• Port C: 8-bit general purpose I/O (28-pin versions only)
• Each port features:
  • Data direction registers
  • Pull-down control registers
  • Interrupt capability on select pins

Timers

The HC705XX7 includes two timer modules:

• Core Timer:
  • 8-bit prescaler
  • Real-time interrupt capability
  • Watchdog timer function
• Programmable Timer:
  • 16-bit counter
  • Input capture capability
  • Output compare capability
  • Timer overflow detection

Analog Subsystem

The integrated analog features include:

• 8-bit A/D converter
• Multiple analog input channels
• Voltage comparator
• Current source
• Temperature sensing diode
• Sample and hold capability

Serial Interface

The Simple Serial Interface (SIOP) provides:

• Full-duplex communication
• Programmable baud rate
• Master/slave operation
• Interrupt-driven operation

Development Support

The HC705XX7 is supported by:

• In-circuit emulators
• EPROM programmers
• Assemblers and C compilers
• Evaluation boards