DESCRIPTION

The 4280 Group is a 4-bit single-chip microcomputer designed with CMOS technology for remote control transmitters. The 4280 Group has 7 carrier waves and enables fabrication of 8 × 7 key matrix.

FEATURES

• Number of basic instructions ............................................. 62

• Minimum instruction execution time ............................ 8.0 µs

(at f(XIN) = 4.0 MHz, system clock = f(XIN)/8, VDD=3.0 V)

• Supply voltage ................................................. 1.8 V to 3.6 V

• Subroutine nesting ..................................................... 4 levels

• Timer

Timer 1 ................................................................... 8-bit timer

with a reload register and carrier wave output auto-control

function

• Carrier wave output function (port CARR)

f(XIN), f(XIN)/4, f(XIN)/8, f(XIN)/12

f(XIN)/64, f(XIN)/96, “H” output fixed

• Logic operation function (XOR, OR, AND)

• RAM back-up function

• Key-on wakeup function (ports D7, E0–E2, G0–G3) ............. 8

• I/O port (ports D, E, G, CARR) .......................................... 16

• Oscillation circuit ..................................... Ceramic resonance

• Watchdog timer

• Power-on reset circuit

• Voltage drop detection circuit ......................... Typical:1.50 V

APPLICATION

Various remote control transmitters