MAX7349AEG-T Maxim Integrated, MAX7349AEG-T Datasheet - Page 9

• Manufacturer Part Number: MAX7349AEG-T
• Description: Peripheral Drivers & Components - PCIs Low-EMI Key Switch & Sounder Controller
• Manufacturer: Maxim Integrated

Table 2. Key-Switch Mapping
Table 3. 2-Wire Interface Address Map
The MAX7347/MAX7348/MAX7349 have two 7-bit long
slave addresses (Figure 6). The bit following a 7-bit
slave address is the R/W bit, which is low for a write
command and high for a read command.
The first 4 bits (MSBs) of the MAX7347/MAX7348/
MAX7349 slave addresses are always 0111. Slave
address bits A3, A2, and A1 correspond, by the matrix
in Table 3, to the states of the device address input
AD0, and A0 corresponds to the R/W bit. MAX7347/
MAX7348/MAX7349 use two slave addresses, one for
the main key-scan controller, and one for the sounder
PIN AD0
ROW0
ROW1
ROW2
ROW3
ROW4
ROW5
ROW6
ROW7
PIN
GND
SDA
SCL
V+
KEY 0
KEY 1
KEY 2
KEY 3
KEY 4
KEY 5
KEY 6
KEY 7
COL0
A7
0
0
0
0
_______________________________________________________________________________________
2-Wire Interfaced Low-EMI Key Switch
A6
1
1
1
1
KEY 10
KEY 11
KEY 12
KEY 13
KEY 14
KEY 15
COL1
KEY 8
KEY 9
A5
1
1
1
1
Slave Addresses
COL2/PORT2 COL3/PORT3 COL4/PORT4 COL5/PORT5 COL6/PORT6 COL7/PORT7
DEVICE ADDRESS
KEY 16
KEY 17
KEY 18
KEY 19
KEY 20
KEY 21
KEY 22
KEY 23
A4
1
1
1
1
A3
0
0
1
1
KEY 24
KEY 25
KEY 26
KEY 27
KEY 28
KEY 29
KEY 30
KEY 31
and Sounder Controllers
A2
0
1
0
1
controller. The AD0 input can be connected to any of
four signals: GND, V+, SDA, or SCL, giving four possible
slave address pairs, allowing up to four MAX7348/
MAX7349 devices to share the bus. Only one MAX7347
can share the bus. The MAX7347 AD0 input is internally
connected to GND.
The MAX7347/MAX7348/MAX7349 monitor the bus
continuously, waiting for a START condition followed by
its slave address. When MAX7347/MAX7348/MAX7349
recognize their slave address, they acknowledge and
are then ready for continued communication.
KEY 32
KEY 33
KEY 34
KEY 35
KEY 36
KEY 37
KEY 38
KEY 39
A1
0
1
0
1
0
1
0
1
A0 R/W
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
KEY 40
KEY 41
KEY 42
KEY 43
KEY 44
KEY 45
KEY 46
KEY 47
Key-scan controller write
Key-scan controller read
Sounder controller write
Sounder controller read
Key-scan controller write
Key-scan controller read
Sounder controller write
Sounder controller read
Key-scan controller write
Key-scan controller read
Sounder controller write
Sounder controller read
Key-scan controller write
Key-scan controller read
Sounder controller write
Sounder controller read
KEY 48
KEY 49
KEY 50
KEY 51
KEY 52
KEY 53
KEY 54
KEY 55
FUNCTION
KEY 56
KEY 57
KEY 58
KEY 59
KEY 60
KEY 61
KEY 62
KEY 63
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