DESCRIPTION

The 3820 group is the 8-bit microcomputer based on the 740 family core technology. The 3820 group has the LCD drive control circuit and the serial I/ O as additional functions.

The various microcomputers in the 3820 group include variations of internal memory size and packaging. For details, refer to the section on part numbering.

For details on availability of microcomputers in the 3820 group, refer to the section on group expansion.

FEATURES

• Basic machine-language instructions ....................................... 71

• The minimum instruction execution time ............................ 0.5 µs

(at 8MHz oscillation frequency)

• Memory size

ROM .................................................................. 4 K to 32 K bytes

RAM ................................................................. 192 to 1024 bytes

• Programmable input/output ports ............................................. 43

• Software pull-up/pull-down resistors (Ports P0-P7 except Port P40)

• Interrupts .................................................. 16 sources, 16 vectors

(includes key input interrupt)

• Timers ........................................................... 8-bit ✕ 3, 16-bit ✕ 2

• Serial I/O1 ..................... 8-bit ✕ 1 (UART or Clock-synchronized)

• Serial I/O2 .................................... 8-bit ✕ 1 (Clock-synchronized)

• LCD drive control circuit

Bias ................................................................................... 1/2, 1/3

Duty ............................................................................ 1/2, 1/3, 1/4

Common output .......................................................................... 4

Segment output ......................................................................... 40

• 2 Clock generating circuit

Clock (XIN-XOUT) .................................. Internal feedback resistor

Sub-clock (XCIN-XCOUT).......... Without internal feedback resistor

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

• Watchdog timer ............................................................. 15-bit ✕ 1

• Power source voltage

In high-speed mode ....................................................4.0 to 5.5 V

(at 8MHz oscillation frequency and high-speed selected)

In middle-speed mode ................................................2.5 to 5.5 V

(at 8MHz oscillation frequency and middle-speed selected)

In low-speed mode ......................................................2.5 to 5.5 V

(Extended operating temperature version: 3.0 V to 5.5 V)

• Power dissipation

In high-speed mode ........................................................... 32 mW

(at 8 MHz oscillation frequency)

In low-speed mode ..............................................................45 µW

(at 32 kHz oscillation frequency, at 3 V power source voltage)

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

(Extended operating temperature version: –40 to 85°C)

APPLICATIONS

Household appliances, consumer electronics, etc.