GENERAL DESCRIPTION
TheAPU4006is a single-chip 4-bit microcontroller with LCD drivers. It can drive up to 3 common time 20 segments, i.e. 60 segments LCD driver. This 4-bit microcontroller contains a 4-bit parallel processing ALU, 1024 x 15-bit program ROM, 48 x 4-bit data RAM, input ports, alarm driver, timer, clock generator, crystal and RC oscillator circuit, LCD driver and 70 powerful instructions in a single chip. It uses HALT instruction to stop all internal operations other than the timer, clock generator, crystal/RC oscillator and LCD driver. Very low current dissipation can be easily achieved by combining 4 types of interrupt function and HALT instruction to minimize the operation cycle.

FEATURES
• Very low current dissipation.
• Wide operating voltage range.
• Supports both Ag and Li batteries.
• Powerful instruction set.
• 4-level subroutine nesting (including interrupt).
• 4 event driven interrupts, 2 external and 2 internal.
• ROM size: 1024 x 15 bits.
• RAM size: 48 x 4 bits.
• Input ports: 1 port/ 4 pins (M-PORT).
• Control output: ALARM.
• LCD driver outputs (can drive up to 60 LCD segments).
• Mask option to select 3 LCD drive modes: static, duplex 1/2 duty 1/2 bias, 1/3 duty 1/2 bias.
• Mask option permits LCD driver output pins to be used for DC output ports. Up to 20 pins are available. SEG13-SEG20 can be selected by open-drain output.
• Segment PLA circuit permits any layout on the LCD panel.
• Built-in clock generator (crystal or RC).
• Built-in voltage doubler, halver.