pca9543bpw NXP Semiconductors, pca9543bpw Datasheet - Page 7

• Manufacturer Part Number: pca9543bpw
• Description: Pca9543a/pca9543b/pca9543c 2-channel I2c-bus Switch With Interrupt Logic And Reset
• Manufacturer: NXP Semiconductors

NXP Semiconductors
PCA9543A_43B_43C_4
Product data sheet
6.3 RESET input
6.4 Power-on reset
6.5 Voltage translation
Remark: Two interrupts can be active at the same time.
The RESET input is an active LOW signal which may be used to recover from a bus fault
condition. By asserting this signal LOW for a minimum of t
registers and I
be connected to V
When power is applied to V
a reset condition until V
and the PCA9543A 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 PCA9543A are constructed such that the V
be used to limit the maximum voltage that will be passed from one I
Figure 8
was generated using the data specified in
sheet). In order for the PCA9543A to act as a voltage translator, the V
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
Fig 8. Pass gate voltage versus supply voltage
(1) maximum
(2) typical
(3) minimum
shows the voltage characteristics of the pass gate transistors (note that the graph
2
C-bus state machine and will deselect all channels. The RESET input must
DD
V
through a pull-up resistor.
o(sw)
(V)
Rev. 04 — 20 October 2006
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 PCA9543A in
2.5
2-channel I
2
C-bus state machine are initialized to their default
3.0
POR
3.5
Section 10 “Static characteristics”
2
C-bus switch with interrupt logic and reset
. At this point, the reset condition is released
4.0
PCA9543A/43B/43C
(1)
(2)
(3)
4.5
002aaa964
5.0
V
WL
DD
, the PCA9543A will reset its
(V)
5.5
2
C-bus to another.
o(sw)
© NXP B.V. 2006. All rights reserved.
o(sw)
DD
voltage should
DD
should be
of this data
must be
voltage can
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