87L42CJ Technical Summary

Overview

The COP87L42CJ is an advanced 8-bit microcontroller from National Semiconductor's COP8 family. It features a memory-mapped architecture with integrated peripherals, making it suitable for a wide range of embedded control applications. The device is designed for low-power operation while maintaining high performance, with features such as MICROWIRE/PLUS™ serial I/O and a versatile 16-bit timer/counter.

Key Features

• 8-bit Memory Mapped Architecture: Efficient memory utilization with a unified address space
• MICROWIRE/PLUS™ Serial I/O: Enhanced serial communication interface for peripheral connectivity
• 16-bit Timer/Counter: Flexible timing operations with capture/compare capabilities
• Low Power Consumption: Optimized for battery-powered applications
• On-chip Oscillator: Supports both crystal and RC oscillator configurations
• Wide Operating Voltage: Typically 2.7V to 5.5V operation
• Multiple I/O Ports: Configurable digital I/O with programmable options
• Watchdog Timer: Built-in system reliability feature

Applications

The COP87L42CJ is designed for a variety of embedded control applications, including:

• Consumer electronics
• Industrial control systems
• Automotive electronics
• Medical devices
• Smart sensors
• Home automation systems
• Battery-powered devices
• Peripheral control units

Electrical Characteristics

Absolute Maximum Ratings

• Supply Voltage (Vcc): -0.3V to +6.5V
• Input Voltage (any pin): -0.3V to Vcc+0.3V
• Operating Temperature Range: -40°C to +85°C
• Storage Temperature Range: -65°C to +150°C

Recommended Operating Conditions

• Supply Voltage (Vcc): 2.7V to 5.5V
• Operating Temperature: -40°C to +85°C
• Input High Voltage (VIH): 0.7Vcc to Vcc
• Input Low Voltage (VIL): 0V to 0.3Vcc

DC Characteristics

• Supply Current (Active Mode @ 5V, 10MHz): 5mA typical
• Supply Current (Standby Mode): 50μA typical
• Input Leakage Current: ±1μA maximum
• Output Low Voltage (IOL = 10mA): 0.4V maximum
• Output High Voltage (IOH = -10mA): Vcc-0.7V minimum

AC Characteristics

• Instruction Cycle Time: 400ns @ 10MHz
• Reset Pulse Width: 10μs minimum
• Serial Clock Frequency (MICROWIRE): 2.5MHz maximum
• Timer Input Frequency: 5MHz maximum

Package Information

Physical Dimensions

The COP87L42CJ is available in a 28-pin PLCC (Plastic Leaded Chip Carrier) package with the following dimensions:

• Package Type: PLCC-28
• Body Size: 11.43mm x 11.43mm
• Lead Pitch: 1.27mm
• Lead Count: 28
• Package Height: 3.43mm maximum

Pin Configuration

The 28-pin PLCC package has the following pin assignments:

• Pins 1-4, 25-28: Port A (PA0-PA7)
• Pins 5-8: Port B (PB0-PB3)
• Pins 9-12: Port C (PC0-PC3)
• Pin 13: Vcc (Power Supply)
• Pin 14: GND (Ground)
• Pin 15: RESET (Active Low Reset Input)
• Pins 16-17: Oscillator Input/Output
• Pins 18-20: Timer/Counter I/O
• Pins 21-24: MICROWIRE/PLUS™ Interface

Functional Description

CPU Core

The COP87L42CJ features an 8-bit CPU core with a comprehensive instruction set optimized for control applications. The architecture includes:

• 8-bit ALU with accumulator
• 16-bit program counter
• 8-bit stack pointer
• Condition code register
• Direct and indirect addressing modes

Memory Organization

The microcontroller features a unified memory space with:

• 1KB to 4KB of ROM (varies by specific model)
• 64 bytes to 128 bytes of RAM
• Memory-mapped I/O registers
• Special function registers for peripheral control

Peripheral Features

The integrated peripherals include:

• 16-bit Timer/Counter: With capture/compare and PWM capabilities
• MICROWIRE/PLUS™ Interface: Synchronous serial communication
• Multiple I/O Ports: With programmable direction and options
• Watchdog Timer: For system reliability
• Power Management: With multiple low-power modes

Development Support

The COP87L42CJ is supported by a comprehensive development ecosystem including:

• Assemblers and C compilers
• In-circuit emulators
• Evaluation boards
• Programming tools
• Application notes and reference designs

Ordering Information

The device is available in several variants with different memory configurations and temperature ranges. Typical ordering codes include:

• COP87L42CJ-28/VE: Industrial temperature range, PLCC-28 package
• COP87L42CJ-28/VA: Extended temperature range, PLCC-28 package