UPD16431A NEC, UPD16431A Datasheet - Page 6

• Manufacturer Part Number: UPD16431A
• Description: 1/2/ 1/3/ 1/4-DUTY LCD CONTROLLER/DRIVER
• Manufacturer: NEC

KEY MATRIX CONFIGURATION
current I
I
6
2
runs thus resulting in SW1 to be recognized as being ON.
An example of key matrix configurations is shown below.
In this configuration, pressing three or more times may cause OFF switches to be determined to be ON.
For example, if SW2 to SW4 are ON and KS
1) When pressing three or more times is assumed:
2) When pressing twice or more times is assumed:
recognized.
A configuration example is shown below.
A configuration example is shown below. In this configuration, 0 to 2 ON switches can be recognized.
1
is running is supposed to be detected to be ON. However, since SW2 and SW4 are ON, current
KEY
KEY
KEY
KEY
KEY
KEY
KEY
KEY
KEY
KEY
KEY
KEY
I
I
1
2
3
4
1
2
3
4
1
2
2
3
4
1
Select
KS
KS
KS
SW1
SW3
1
1
1
KS
KS
KS
2
2
2
SW2
SW4
KS
KS
KS
3
3
3
KS
KS
KS
4
4
4
KS
KS
KS
5
5
5
1
has been selected (high level) as shown below, SW3 in which
KS
KS
KS
6
6
6
In this configuration, 0 to 32 ON switches can be
KS
KS
KS
7
7
7
KS
KS
KS
8
8
8
Diode A
=
=
=
C
PD16431A