PCA9544APW,112 NXP Semiconductors, PCA9544APW,112 Datasheet - Page 8

• Manufacturer Part Number: PCA9544APW,112
• Description: IC I2C MUX 4CH BI-DIR 20-TSSOP
• Manufacturer: NXP Semiconductors

Specifications of PCA9544APW,112

• Package / Case: 20-TSSOP
• Applications: 4-Channel I²C Multiplexer
• Interface: I²C
• Voltage - Supply: 2.3 V ~ 3.6 V, 4.5 V ~ 5.5 V
• Mounting Type: Surface Mount
• Product: Decoders, Encoders, Multiplexers & Demultiplexers
• Logic Family: PCA
• Number Of Lines (input / Output): 8.0 / 10.0
• Propagation Delay Time: 0.3 ns
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 2.3 V
• Maximum Operating Temperature: + 85 C
• Minimum Operating Temperature: - 40 C
• Mounting Style: SMD/SMT
• Number Of Input Lines: 8.0
• Number Of Output Lines: 10.0
• Power Dissipation: 400 mW
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 568-1045-5; 935275806112; PCA9544APW

NXP Semiconductors
PCA9544A_4
Product data sheet
6.4 Power-on reset
6.5 Voltage translation
When power is applied to V
a reset condition until V
and the PCA9544A registers and I
states (all zeroes), causing all the channels to be deselected. Thereafter, V
lowered below 0.2 V to reset the device.
The pass gate transistors of the PCA9544A are constructed such that the V
be used to limit the maximum voltage that will be passed from one I
Figure 7
was generated using the data specified in
data sheet). In order for the PCA9544A to act as a voltage translator, the V
should be equal to, or lower than the lowest bus voltage. For example, if the main bus was
running at 5 V, and the downstream buses were 3.3 V and 2.7 V, then V
equal to or below 2.7 V to effectively clamp the downstream bus voltages. Looking at
Figure
3.5 V or lower so the PCA9544A supply voltage could be set to 3.3 V. Pull-up resistors can
then be used to bring the bus voltages to their appropriate levels (see
More Information can be found in Application Note AN262, PCA954X family of I
multiplexers and switches .
Fig 7.
(1) maximum
(2) typical
(3) minimum
7, we see that V
shows the voltage characteristics of the pass gate transistors (note that the graph
Pass gate voltage versus supply voltage
V
o(sw)
(V)
o(sw)(max)
Rev. 04 — 15 June 2009
DD
5.0
4.0
3.0
2.0
1.0
2.0
has reached V
DD
, an internal Power-On Reset (POR) holds the PCA9544A in
2.5
will be at 2.7 V when the PCA9544A supply voltage is
2
C-bus state machine are initialized to their default
3.0
4-channel I
POR
3.5
Section 11 “Dynamic characteristics”
. At this point, the reset condition is released
4.0
2
C-bus multiplexer with interrupt logic
(1)
(2)
(3)
4.5
002aaa964
5.0
V
DD
(V)
5.5
PCA9544A
2
C-bus to another.
Figure
© NXP B.V. 2009. All rights reserved.
o(sw)
DD
o(sw)
DD
should be
14).
voltage can
must be
2
voltage
C/SMBus
of this
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