LC75878W
www.onsemi.com
6
Pin Functions
Symbol Pin No. Function Active
I/O
Handling
when
unused
S1 to S73
S74/COM10
S75/COM9
1 to 73
74
75
Segment driver outputs.
The S74/COM10 and S75/COM9 pins can be used as common driver outputs under
the control data.
- O OPEN
COM1 to
COM8
83 to 76 Common driver outputs.
- O OPEN
P1 to P4 84 to 87 General-purpose output ports.
- O OPEN
OSC 96 Oscillator connection.
An oscillator circuit is formed by connecting an external resistor and capacitor at
this pin.
- I/O V
DD
CE 98 Serial data transfer inputs.
These pins are connected to the microcontroller.
CE: Chip enable
CL: Synchronization clock
DI: Transfer data
H I
GND
CL 99 I
DI 100 - I
INH
97 Input that turns the display off and forces the general-purpose output ports low.
• When
INH
is low (V
SS
)
• Display off
S1 to S73 = “L” (V
LCD
4).
S74/COM10, S75/COM9 = “L” (V
LCD
4)
COM1 to COM8 = “L” (V
LCD
4).
• General-purpose output ports P1 to P4 = low (V
SS
)
• When
INH
is high (V
DD
)
• Display on
• The states of the general-purpose output ports can be set by
the PC1 to PC4 control data.
However, serial data can be transferred when the
INH
pin is low.
L I GND
V
LCD
0
90 LCD drive 4/4 bias voltage (high level) supply pin. The level on this pin can be
changed by the display contrast adjustment circuit.
However, (V
LCD
0 - V
LCD
4) must be greater than or equal to 4.5 V.
Also, external power must not be applied to this pin since the pin circuit includes the
display contrast adjustment circuit.
- O OPEN
V
LCD
1
91 LCD drive 3/4 bias voltage (middle level) supply pin. This pin can be used to supply
the 3/4 (V
LCD
0 - V
LCD
4) voltage level externally.
- I OPEN
V
LCD
2
92 LCD drive 2/4 bias voltage (middle level) supply pin. This pin can be used to supply
the 2/4 (V
LCD
0 - V
LCD
4) voltage level externally.
- I OPEN
V
LCD
3
93 LCD drive 1/4 bias voltage (middle level) supply pin. This pin can be used to supply
the 1/4 (V
LCD
0 - V
LCD
4) voltage level externally.
- I OPEN
V
LCD
4
94 LCD drive 0/4 bias voltage (low level) supply pin. Fine adjustment of the display
contrast can be implemented by connecting an external variable resistor to this pin.
However, (V
LCD
0 - V
LCD
4) must be greater than or equal to 4.5 V, and V
LCD
4
must be in the range 0 V to 1.5 V, inclusive.
- I GND
V
DD
88 Logic block power supply connection. Provide a voltage of between 2.7 and 6.0V.
- - -
V
LCD
89 LCD driver block power supply connection. Provide a voltage of between 7.0 and
11.0 V when the display contrast adjustment circuit is used and provide a voltage of
between 4.5 and 11.0 V when the circuit is not used.
- - -
V
SS
95 Power supply connection. Connect to ground.
- - -
