BU34381 ROHM Co. Ltd., BU34381 Datasheet - Page 9

• Manufacturer Part Number: BU34381
• Description: Single-chip 4-bit Microcontroller For
• Manufacturer: ROHM Co. Ltd.

FHardware descriptions
(1)
5.5V)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
Optical disc ICs
Operates on a single power supply (V
Memory size
Instruction execution time (1 cycle instruction)
Subroutine nesting : 8 levels
Interrupts : 6 factors
ROM data table function (data table area: 12KB)
Two energy-saving modes (STOP / HALT)
Internal 20-segment LCD driver adaptable for vari-
ous types of displays
Internal bias resistor (3 stages, approx. 50k )
External
Internal (time counter, serial I / O) : 3 factors
Bias
Duty settings : 1 / 3, 1 / 4 (programmable)
ROM
RAM
LCD display RAM : 20
1.5 sec: (at 4MHz)
: 1 / 3
: 12288
: 512
4 bits
4 bits
DD
: 3 factors
8 bits
= 2.7 X
(9)
CMOS output
(10) Internal remote control receiver (pulse width count-
er)
(11) Internal 8-channel, 8-bit A / D converter
(12) A / D input is programmable in 1-bit units as digital
input
(13) Internal 8-bit timer counter (also used as event
counter)
(14) Two internal serial input / outputs (LSB fast) that
simplify interface with external LSI chips
(15) 12 input / outputs (programmable pull-up)
(16) 5 inputs (programmable pull-up)
LCD segment output is program-switchable to
All 20 segments can be selected in 4-bit
groups
Resetting: CMOS small-current output port,
LOW polarity
BU34381
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