DS92LX2121SQE/NOPB National Semiconductor, DS92LX2121SQE/NOPB Datasheet - Page 27

• Manufacturer Part Number: DS92LX2121SQE/NOPB
• Description: IC SER/DESER 10-50MHZ 40-LLP
• Manufacturer: National Semiconductor

Specifications of DS92LX2121SQE/NOPB

• Serdes Function: Serializer
• Data Rate: 100Kbps
• Ic Output Type: CML
• No. Of Inputs: 21
• No. Of Outputs: 2
• Supply Voltage Range: 3V To 3.6V
• Driver Case Style: LLP
• No. Of Pins: 40
• Msl: MSL 3 - 168 Hours
• Rohs Compliant: Yes
• Leaded Process Compatible: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Other names: DS92LX2121SQE/NOPBTR

SLAVE CLOCK STRETCHING
In order to communicate and synchronize with remote de-
vices on the I
slave clock stretching must be supported by the I
controller/host device. The chipset utilizes bus clock stretch-
ing (holding the SCL line low) during data transmission; where
the I2C slave pulls the SCL line low on the 9th clock of every
I
will not control the clock and only stretches it until the remote
peripheral has responded; which is typically in the order of 12
μs (typical).
TABLE 3. DS92LX2121 RID Resistor Values
TABLE 4. DS92LX2122 RID Resistor Values
2
C data transfer (before the ACK signal). The slave device
Resistor RID kΩ
Resistor RID kΩ
12.1k
39.0k
12.1k
39.0k
GND
GND
2.0k
4.7k
8.2k
2.0k
4.7k
8.2k
0
0
2
C bus through the bi-directional control channel,
7b' 110 0000 (h'60)
7b' 110 0001 (h'61)
7b' 110 0010 (h'62)
7b' 110 0011 (h'62)
7b' 110 0100 (h'62)
7b' 110 0110 (h'66)
7b' 101 1010 (h'5A)
7b' 101 1011 (h'5B)
7b' 101 1100 (h'5C)
7b' 101 1110 (h'5E)
7b' 101 1000 (h'58)
7b' 101 1001 (h'59)
Address 7'b
Address 7'b
FIGURE 24. Serial Control Bus Connection
CAD Values - DS92LX2122 Des
CAD Values - DS92LX2121 Ser
2
C master
27
CAD PIN ADDRESS DECODER
The CAD pin is used to decode and set the physical slave
address of the Serializer/Deserializer (I
six devices on the bus using only a single pin. The pin sets
one of six possible addresses for each Serializer/Deserializer
device. The pin must be pulled to VDD (1.8V, NOT VDDIO))
with a 10 kΩ resistor and a pull down resistor (RID) of the
recommended value to set the physical device address. The
recommended maximum resistor tolerance is 0.1% worst
case (0.2% total tolerance).
Address 8'b 0 appended (WRITE)
Address 8'b 0 appended (WRITE)
8b' 1100 1100 (h'CC)
8b' 1011 1100 (h'BC)
8b' 1100 0000 (h'C0)
8b' 1100 0010 (h'C2)
8b' 1100 0100 (h'C4)
8b' 1101 0110 (h'C6)
8b' 1101 1000 (h'C8)
8b' 1011 0000 (h'B0)
8b' 1011 0010 (h'B2)
8b' 1011 0100 (h'B4)
8b' 1011 0110 (h'B6)
8b' 1011 1000 (h'B8)
30125143
2
C only) to allow up to
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