PDF LC75812PT Datasheet ( Hoja de datos )

		


Ordering number : ENA1417B
LC75812PT
CMOS IC
1/8, 1/9 Duty Dot Matrix LCD Display
Controllers/Drivers with Key Input Function
http://onsemi.com
Overview
The LC75812PT is 1/8, 1/9 duty dot matrix LCD display controllers/drivers that support the display of characters,
numbers, and symbols. In addition to generating dot matrix LCD drive signals based on data transferred serially from
a microcontroller, the LC75812PT also provide on-chip character display ROM and RAM to allow display systems to
be implemented easily. These products also provide up to 3 general-purpose output ports and incorporate a key scan
circuit that accepts input from up to 35 keys to reduce printed circuit board wiring.
Features
• Key input function for up to 35 keys (A key scan is performed only when a key is pressed.)
• Controls and drives a 5×7 or 5×8 dot matrix LCD.
• Supports accessory display segment drive (up to 65 segments)
• Display technique: 1/8 duty 1/4 bias drive (5×7 dots)
1/9 duty 1/4 bias drive (5×8 dots)
• Display digits: 13 digits×1 line (5×7 dots), 12 digits×1 line (5×8 dots)
• Display control memory
CGROM: 240 characters (5×7 or 5×8 dots)
CGRAM: 16 characters (5×7 or 5×8 dots)
ADRAM: 13×5 bits
DCRAM: 52×8 bits
• Instruction function
Display on/off control
Display shift function
• Sleep mode can be used to reduce current drain.
• Built-in display contrast adjustment circuit
• Switching between key scan output and general-purpose output ports can be controlled with instructions.
• PWM output for adjusting the LED backlight brightness
• The frame frequency of the common and segment output waveforms can be controlled by instructions.
• Serial data control of switching between the RC oscillator operating mode and external clock operating mode.
• Independent LCD driver block power supply VLCD
• A voltage detection type reset circuit is provided to initialize the IC and prevent incorrect display.
• The INH pin is provided. This pin turns off the display, disables key scanning, and forces the general-purpose
output ports to the low level.
• RC oscillator circuit
• CCB is ON Semiconductor® ’s original format. All addresses are managed
by ON Semiconductor® for this format.
• CCB is a registered trademark of Semiconductor Components Industries, LLC.
Semiconductor Components Industries, LLC, 2013
July, 2013
31710HKIM 20100223-S00011,S00012,S00013/N1809HKIM/52709HKIM No.A1417-1/54

1 page



(1) When CL is stopped at the low level
CE
VIH1
CL 50%
VIL1
DI VIH1
VIL1
DO
tds
tφH
tdh
tφL
LC75812PT
VIH1
tcp tcs
D0
(2) When CL is stopped at the high level
[Figure 2]
tdc
VIL1
tch
D1
tdr
VIH1
CE
tφL tφH VIH1
CL 50%
VIL1
tcp tcs
DI
VIH1
VIL1
tds tdh
DO D0
[Figure 3]
(3) OSC pin clock timing in external clock operating mode
D1
tdc
OSC
VIH2
50%
VIL2
tCKH
tCKL
[Figure 4]
fCK=
1
tCKH + tCKL
[kHz]
DCK=
tCKH
tCKH + tCKL
×100[%]
VIL1
tch
tdr
No.A1417-5/54

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Serial Data Input
(1) When CL is stopped at the low level
LC75812PT
CE
CL
DI 0 1 0 0 0 0 1 0 D0 D1 D2 D3 D4
D118 D119
B0 B1 B2 B3 A0 A1 A2 A3
Instruction data (Up to 120 bits)
DO
(2) When CL is stopped at the high level
CE
CL
DI 0 1 0 0 0 0 1 0 D0 D1 D2 D3 D4
D118 D119
B0 B1 B2 B3 A0 A1 A2 A3
Instruction data (Up to 120 bits)
DO
• B0 to B3, A0 to A3: CCB address 42H
• D0 to D119: Instruction data
The data is acquired on the rising edge of the CL signal and latched on the falling edge of the CE signal. When
transferring instruction data from the microcontroller, applications must assure that the time from the transfer of one set
of instruction data until the next instruction data transfer is significantly longer than the instruction execution time.
No.A1417-11/54

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