三合微科股�½有限公司
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AM
H
OP
Microelectronics Corp.
SM5221-001/002
32 KEYS ENCODER
(2) Key Scan
A pull-down resistor is inserted
keys are depressed simultaneously, transmission is disabled by the multi-depression
prevention circuit.
When a key is depressed, reading of the custom code and key data code is started, and DOUT
output begins 36 ms later, so that if the key is being depressed during this 36 ms interval one
transmission is performed. If a key is held down for 108 ms or longer, consecutive
transmissions of the leader code only are performed while the key is depressed.
Key Input
Ex. f OSC = 455 kHz
MIN. 36 ms
58.5 to 76.5 ms
108 ms
108 ms
(3) Data Code D
7
Control
Data code D7 can be controlled by this pin, allowing 64 kinds of data to be transmitted.
D7 is set to "0" by connecting the SEL pin to VDD, and to "1" by connecting the SEL pin to
VSS. As the input of this pin is high-impedance, it must be connected to either VDD or VSS.
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V.2.0 Mar 8,2002
SAMHOP [ SAMHOP MICROELECTRONICS CORP. ]
