lc75700t Sanyo Semiconductor Corporation, lc75700t Datasheet - Page 13

• Manufacturer Part Number: lc75700t
• Description: Key Scan Ic
• Manufacturer: Sanyo Semiconductor Corporation

3. Output pin states during a reset
*4. Since this output pin is an open-drain output, a pull-up resistor of between 1 and 10 kΩ is required. This pin remains high during the reset period even if a
Sample Application Circuit
From the controller
key data read operation is performed.
To the controller
KS4/P4 to KS6/P2
To the controller
Output pins
KS1 to KS3
power supply
Note:
DO
P1
*5.
*6.
*7.
+5 V
When the power is first applied, it must be initialized by RES = "L".
The DO pin,being an open-drain output, requires a pull-up resistor. Select a resistance (between 1 and 10 k ) appropriate
for the capacitance of the external wiring so that signal waveforms are not degraded.
Each of The KS4/P4 to KS6/P2 pins must be set to either the key scan output port or the general-purpose output port.
*6
State during a reset
H *4
L
L
L
V DD
V SS
RES *5
CE
CL
DI
DO
OSC
LC75700T
*7
KS6/P2
KS5/P3
KS4/P4
KS3
KS2
KS1
KI5
KI4
KI3
KI2
KI1
P1
(P1)
(P2)
(P3)
(P4)
(General-purpose output ports)
Used with the backlight
controller or other circuit.
Key matrix
(up to 30 keys)
No. 7632-13/16