Overview
The LC665304A, LC665306A, LC665308A, LC665312A, and LC665316A are 4-bit CMOS microcontrollers that integrate on a single chip all the functions required in a system controller, including ROM, RAM, I/O ports, a serial interface, 16-value comparator inputs, timers, interrupt functions, and an optional sub-oscillator circuit. These microcontrollers are available in a 48-pin package.

Features and Functions
• On-chip ROM capacitiy of 4, 6, 8, 12, and 16 kilobytes, and an on-chip RAM capacity of 512 × 4 bits.
• Fully supports the LC66000 Series common instruction set (128 instructions).
• I/O ports: 42 pins
• A sub-oscillator circuit can be used (option) This circuit allows power dissipation to be reduced by operating at lower speeds.
• 8-bit serial interface: two circuits (can be connected in cascade to form a 16-bit interface)
• Instruction cycle time: 0.95 to 10 µs (at 3 to 5.5 V)
• Powerful timer functions and prescalers
    — Time limit timer, event counter, pulse width measurement, and square wave output using a 12-bit timer.
    — Time limit timer, event counter, PWM output, and square wave output using an 8-bit timer.
    — Time base function using a 12-bit prescaler.
• Powerful interrupt system with 8 interrupt factors and 8 interrupt vector locations.
    — External interrupts: 3 factors/3 vector locations
    — Internal interrupts: 5 factors/5 vector locations
• Flexible I/O functions 16-value comparator inputs, 20-mA drive outputs, inverter circuits, pull-up and open-drain circuits selectable as options.
• Optional runaway detection function (watchdog timer)
• 8-bit I/O functions
• Power saving functions using halt and hold modes.
• Packages: DIP48S, QIP48E (QFP48E)
• Evaluation LSIs: LC66599 (evaluation chip) + EVA800/850-TB662YXX2 LC66E5316(on-chip EPROM microcontroller)