ST7277 HCMOS Microcontroller Technical Summary

Overview

The ST7277 is a high-performance HCMOS microcontroller unit (MCU) from the ST7 family, designed for embedded control applications requiring efficient processing and versatile peripheral integration. This 8-bit microcontroller combines advanced architecture with dedicated peripherals, making it suitable for a wide range of industrial, automotive, and consumer applications.

Built on a robust HCMOS process, the ST7277 offers enhanced power efficiency and operational reliability. Its core features include true bit manipulation capabilities and an 8x8 unsigned multiplier, enabling efficient arithmetic operations for real-time control tasks.

Key Features

• Advanced 8-bit ST7 Core with optimized instruction set for efficient processing
• True Bit Manipulation capability for granular control of I/O and registers
• 8x8 Unsigned Multiplier for efficient arithmetic operations
• Wide Operating Voltage Range (typically 3.0V to 5.5V)
• Low Power Consumption with multiple power-saving modes
• On-chip Memory including program Flash and data RAM
• Robust Peripheral Set including timers, communication interfaces, and analog components
• Enhanced EMI/EMS Performance for operation in noisy environments
• Industrial Temperature Range support (-40°C to +85°C or wider)

Applications

The ST7277 microcontroller is designed for versatile applications across multiple industries:

Industrial Control Systems

• Programmable logic controllers (PLCs)
• Motor control units
• Sensor interfaces
• Process control equipment

Automotive Electronics

• Body control modules
• Dashboard instrumentation
• Simple engine management systems
• Lighting control units

Consumer Electronics

• Home appliances
• Power tools
• Gaming peripherals
• Remote control systems

Medical Devices

• Portable monitoring equipment
• Diagnostic devices
• Therapy control systems

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage: -0.3V to +6.5V
• Input Voltage on any pin: -0.3V to V_DD+0.3V
• Storage Temperature Range: -55°C to +150°C
• Maximum Junction Temperature: +150°C

Recommended Operating Conditions

• Operating Voltage Range: 3.0V to 5.5V
• Ambient Temperature Range:
  • Commercial: 0°C to +70°C
  • Industrial: -40°C to +85°C
  • Extended: -40°C to +105°C (selected versions)
• Clock Frequency: Up to 8MHz (varies by voltage)

Power Consumption

• Active Mode (8MHz): 5mA typical
• Wait Mode: 1.5mA typical
• Halt Mode: 10μA typical

Timing Characteristics

• CPU Clock Cycle Time: 125ns (8MHz operation)
• External Interrupt Response Time: 500ns typical
• Reset Pulse Width: 10μs minimum

Package Information

The ST7277 is available in multiple package options to suit various application requirements:

DIP (Dual In-line Package)

• 28-pin configuration
• Through-hole mounting
• Package dimensions: 35.56mm x 7.62mm
• Ideal for prototyping and educational use

SOIC (Small Outline Integrated Circuit)

• 28-pin configuration
• Surface mount technology
• Package dimensions: 17.9mm x 7.5mm
• Suitable for space-constrained applications

TSSOP (Thin Shrink Small Outline Package)

• 32-pin configuration
• Ultra-thin profile (1.0mm height)
• Package dimensions: 9.7mm x 4.4mm
• Optimal for high-density PCB designs

QFN (Quad Flat No-leads)

• 32-pin configuration
• Extremely compact footprint
• Package dimensions: 5mm x 5mm
• Excellent thermal performance

Development Support

STMicroelectronics provides comprehensive development support for the ST7277 microcontroller:

• ST7 Toolchain including assembler, linker, and C compiler
• Evaluation Boards for rapid prototyping
• Debugging Tools including in-circuit emulators and debug probes
• Application Notes covering various implementation scenarios
• Reference Designs for common applications
• Technical Support through STMicroelectronics' global network

Conclusion

The ST7277 HCMOS microcontroller represents a versatile and reliable solution for embedded control applications. With its combination of processing power, peripheral integration, and power efficiency, it addresses the needs of diverse market segments. The device's robust architecture, coupled with comprehensive development support, makes it an excellent choice for both new designs and upgrades to existing systems.

Engineers can leverage the ST7277's features to create cost-effective yet powerful solutions, benefiting from STMicroelectronics' proven quality and reliability in microcontroller technology.