Key And Display Circuit - Samsung S3F84B8 Design Manual

S3F84B8_ALL-IN-ONE IH COOKER_AN_REV 0.00

2.6.3 KEY AND DISPLAY CIRCUIT

Figure 2-9 shows the circuit diagram for key and display.
5V
R32
constant R29
constant R8 1
NC
constant 2
DIO
3
CLK
4
STB
KEY1
5
KEY 1
KEY2
6
KEY 2
5V
7
VDD0
SEG1/KS1
8
SEG1/KS1
SEG2/KS2
9
SEG2/KS2
SEG3/KS3
10
SEG3/KS3
SEG4/KS4
11
SEG4/KS4
SEG5/KS5
12
SEG5/KS5
SEG6/KS6
13
SEG6/KS6
SEG7/KS7
14
SEG7/KS7
K4 KEY
KEY1
K3
R18 constant
0
KEY2
KEY
constant
R17
R9
0
There are eight keys for power on, power grade selection, and some LEDs to display the operating status and
power grade. TM1628 controls the key and display circuit. MCU communicates with TM1628 through three I/Os:
DIO for data transfer, CLK as serial clock, and STB for chip enable.
1 R6 2
U2
constant
28
GND0
GRID1
27
GRID1
GRID2
26
GRID2
GND
25
GND
GRID3
24
GRID3
GRID4
23
GRID4
GND
22
GND1
5V
21
VDD1
GRID5
20
SEG14/GRID5
GRID6
19
SEG13/GRID6
GRID7
18
SEG12/GRID7
17
SEG10
16
SEG9
SEG8/KS8
15
SEG8/KS8
TM1628
K2 KEY
K1 K5 K6
KEY KEY KEY
constant constant constant
R7 R10
Figure 2-9
D1
SEG1/KS1
1
LED
D2
SEG4/KS4
1
LED
D3
1
LED
D4
SEG3/KS3
1
LED
K7 K8
KEY KEY
constant constant
R11 R12 R14
Key and Display Circuit
2-14
2 HARDWARE IMPLEMENTATION
2
2
D8
2
2
4LED
GRID7
5V
C26
+
PF
GND
0
constant
C27
PF