P82B715TD,112 NXP Semiconductors, P82B715TD,112 Datasheet - Page 4

• Manufacturer Part Number: P82B715TD,112
• Description: IC I2C BUS EXTENDER 8-SOIC
• Manufacturer: NXP Semiconductors
• Type: Bus Extenderr

Specifications of P82B715TD,112

• 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
• Number Of Lines (input / Output): 1 / 1
• 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
• Logic Type: I2C Bus Extender
• Mounting Style: SMD/SMT
• Number Of Input Lines: 1
• Number Of Output Lines: 1
• Output Current: 60 mA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 568-3981-5; 935154770112; P82B715TD; P82B715TD

NXP Semiconductors
7. Functional description
P82B715_8
Product data sheet
7.1 Sx, Sy: I
The P82B715 is a dual bidirectional logic signal device having unity voltage gain in both
directions, but 10 current amplification in one direction that allows increasing the
allowable I
and requires no external directional control. It uses unidirectional analog current
amplification to increase the current sink capability of I
to change the I
I
cables and without degradation of system performance.
P82B715 provides current amplification from its I
bus. Whenever current is flowing out of Sx, into an I
P82B715 will sink ten times that current into Lx to drive the buffered bus LOW (see
Figure
To minimize interference and ensure stability, the current rise and fall times of the Lx drive
amplifier are internally controlled.
The P82B715 does not amplify signal currents flowing in the other direction, i.e., into Sx
from the I
buffered side.
The buffered bus logic LOW voltage at Lx simply drives the I
internal 30
depends on the current flowing in the sense resistor so it will be very small when the bus
currents are small, but it is guaranteed not to exceed 100 mV in either direction with full
static I
The unity voltage gain, with signal current amplification dependent on direction, preserves
the multi-master, bidirectional, open-collector/open-drain, characteristic of any connected
I
signal voltage levels will be clamped at (V
the supply voltage V
On the normal side, because the two buffer circuits in the P82B715 are identical, either
the Sx or Sy input pins can be used as the I
2
2
Fig 4.
C-bus, or similar bus systems, to be extended over long distances using conventional
C-bus lines and provides these characteristics to the new low-impedance bus. Bus logic
I
2
C-bus Sx
GND
2
V
4).
C-bus loading.
CC
2
Equivalent circuit: one-half P82B715
C-bus. The Sx pin is driven LOW by current flowing out of Lx to the driver of that
2
2
C-bus system capacitance. It contains identical circuits for each I
C-bus SDA or SCL
resistor. The buffer’s offset voltage (the difference between Sx and Lx)
2
C-bus specification limit of 400 pF to a 4 nF system limit. This allows
I
CC
Sx
Rev. 08 — 9 November 2009
.
CURRENT
SENSE
30
CC
I
Sx
2
C-bus SDA data line, or the SCL clock line.
+ 0.7 V), but otherwise are independent of
= I
Lx
2
C-bus to its low-impedance or buffered
2
C-bus chip driving the I
2
C-bus chips by a factor of 10 and
I
Sx
2
C-bus at Sx LOW via the
9
I
Sx
I
Lx
P82B715
© NXP B.V. 2009. All rights reserved.
I
2
= 10
C-bus extender
2
2
C-bus signal
Lx buffered bus
C-bus LOW,
I
Sx
002aad688
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