P82B715TD,118 NXP Semiconductors, P82B715TD,118 Datasheet - Page 10

• Manufacturer Part Number: P82B715TD,118
• Description: IC I2C BUS EXTENDER 8-SOIC
• Manufacturer: NXP Semiconductors
• Type: Bus Extenderr

Specifications of P82B715TD,118

• Package / Case: 8-SOIC (3.9mm Width)
• Tx/rx Type: I²C Logic
• Delay Time: 250ns
• Capacitance - Input: 3000pF
• Voltage - Supply: 4.5 V ~ 12 V
• Current - Supply: 22mA
• Mounting Type: Surface Mount
• Logic Family: P82B
• Propagation Delay Time: 250 ns
• Operating Supply Voltage: 4.5 V to 12 V
• Power Dissipation: 300 mW
• Operating Temperature Range: - 40 C to + 85 C
• Input Voltage: 5 V
• Logic Type: I/O Expander
• Maximum Clock Frequency: 400 KHz
• Mounting Style: SMD/SMT
• Output Current: 60 mA
• Output Voltage: 5 V
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 568-1007-2; 935154770118; P82B715TD-T

NXP Semiconductors
P82B715_8
Product data sheet
Fig 9.
MASTER
I
2
C-BUS
5 V
C
Remark: Cable bus pull-ups only fitted at the cable ends, not fitted to modules connected along cable.
Quick design-in point-to-point/multi-point circuit for 5 V bus
4.7 k
SDA
SCL
8.2 Quick design-in point-to-point/multi-point circuit information for 5 V
4.7 k
Sx
Sy
P82B715
bus
With many variables (cable length/capacitance, local capacitive loading on each I
bus voltages, and bus speed), optimizing a design can be complex and requires
significant study of the application note information. The following circuit and simplified
approach has been checked to provide adequate performance in the typical 100 kHz
application and can be easily implemented by just using the values and circuit shown for
either point-to-point application, up to 30 meters long, or in multiple point applications if
additional nodes need to be added along the way.
Specific information on this circuit implementation:
•
•
•
The pull-up on each I
nearest usual value.
The net pull-up on the cable bus can be (V
n = total number of P82B715 modules on the cable. When there are only two
modules, one each end of the cable, the pull-up = (4.5 / 19) = 237 . Make the
pull-ups at each end of the cable equal. Signalling is bidirectional so there is no
advantage optimizing for any one direction. The pull-up at each end will be 474 ,
using 470
The 100 kHz rise time requirement is 1 s. Meeting this requires the product of the
bus capacitance and pull-up resistor on each bus section to be less than 1.18 s. That
provides one capacitance limit. With 4.7 k pull-ups the I
while the 235
470
Lx
Ly
ESD protection
optional
470
5V1
as the nearest usual value.
sets a cable bus limit at 5000 pF.
Rev. 08 — 9 November 2009
2
C-bus is (V
twisted pair cable
20 meter Cat5e
protection
optional
ESD
CC
optional
ESD protection
0.4 V) / 1 mA = 4.6 k , using 4.7 k as the
CC
5V1
470
Lx
Ly
5V1
0.5 V) / (21
P82B715
470
Lx
Ly
4.7 k
2
Sx
Sy
P82B715
C-bus limit is 250 pF each,
n) mA where
4.7 k
4.7 k
SDA
SCL
Sx
Sy
P82B715
© NXP B.V. 2009. All rights reserved.
I
2
I
C-bus extender
2
SLAVE
C-BUS
5 V
4.7 k
SDA
SCL
I
002aad817
2
2
SLAVE
C-BUS
C-bus,
5 V
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