GENERAL DESCRIPTION

The 3885 group is the 8-bit microcomputer based on the 740 family core technology.

The 3885 group is designed for Keyboard Controller for the note book PC.

The multi-master I2C-bus interface can be added by option.

FEATURES

● Basic machine-language instructions ...................................... 71

● Minimum instruction execution time .................................. 0.5 µs

(at 8 MHz oscillation frequency)

● Memory size

ROM ................................................................. 32K to 60K bytes

RAM ............................................................... 1024 to 2048 bytes

● Programmable input/output ports ............................................ 72

● Software pull-up transistors ....................................................... 8

● Interrupts ................................................. 22 sources, 16 vectors

● Timers ............................................................................. 8-bit ✕ 4

● Watchdog timer ............................................................ 16-bit ✕ 1

● PWM output .................................................................. 14-bit ✕ 2

● Serial I/O....................... 8-bit ✕ 1(UART or Clock-synchronized)

● Multi-master I2C bus interface (option) ........................ 1 channel

● LPC interface .............................................................. 2 channels

● Serialized IRQ .................................................................. 3 factor

● A-D converter ............................................... 10-bit ✕ 8 channels

● D-A converter ................................................. 8-bit ✕ 2 channels

● Comparator circuit ...................................................... 8 channels

● Clock generating circuit ..................................... Built-in 2 circuits

(connect to external ceramic resonator or quartz-crystal oscillator)

● Power source voltage ................................................ 3.0 to 3.6 V

● Power dissipation

In high-speed mode ..........................................................20 mW

(at 8 MHz oscillation frequency, at 3.3 V power source voltage)

In low-speed mode ......................................................... 330 mW

(at 32 kHz oscillation frequency, at 3.3 V power source voltage)

● Operating temperature range.................................... –20 to 85°C

● Supply voltage ................................................. VCC = 3.3 ± 0.3V

● Program/Erase voltage ................................. VPP = 5.0 V ± 10

● Programming method ...................... Programming in unit of byte

● Erasing method

Parallel I/O mode

CPU reprogramming mode

● Program/Erase control by software command

● Number of times for programming/erasing ............................ 100

● Operating temperature range (at programming/erasing)

........................................................................Room temperature