TI PCA9545APWR

PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
FEATURES
19
3
18
4
17
5
6
7
16
15
14
8
13
9
12
10
11
VCC
SDA
SCL
INT
SC3
SD3
INT3
SC2
SD2
INT2
20 19 18 17 16
RESET
INT0
SD0
SC0
INT1
1
15 INT
2
14 SC3
3
13 SD3
4
12 INT3
11
5
6
7
8 9 10
SC2
A1
RESET
INT0
SD0
SC0
INT1
SD1
SC1
2
3
4
5
6
7
8
9
VCC
20
2
1
20
10
11
INT2
1
RGY PACKAGE
(TOP VIEW)
A0
A0
A1
RESET
INT0
SD0
SC0
INT1
SD1
SC1
GND
RGW PACKAGE
(TOP VIEW)
A1
A0
DGV, DW, OR PW PACKAGE
(TOP VIEW)
GND
•
•
•
No Glitch on Power Up
Supports Hot Insertion
Low Standby Current
Operating Power-Supply Voltage Range of
2.3 V to 5.5 V
5.5-V Tolerant Inputs
0 to 400-kHz Clock Frequency
Latch-Up Performance Exceeds 100 mA Per
JESD 78
ESD Protection Exceeds JESD 22
– 2000-V Human-Body Model (A114-A)
– 200-V Machine Model (A115-A)
– 1000-V Charged-Device Model (C101)
SDA
SCL
•
•
•
•
VCC
•
•
•
•
•
1-of-4 Bidirectional Translating Switches
I2C Bus and SMBus Compatible
Four Active-Low Interrupt Inputs
Active-Low Interrupt Output
Active-Low Reset Input
Two Address Pins, Allowing up to Four
Devices on the I2C Bus
Channel Selection Via I2C Bus, In Any
Combination
Power Up With All Switch Channels
Deselected
Low RON Switches
Allows Voltage-Level Translation Between
1.8-V, 2.5-V, 3.3-V, and 5-V Buses
SD1
SC1
GND
INT2
SD2
•
•
•
•
•
•
19
18
17
16
15
14
13
12
SDA
SCL
INT
SC3
SD3
INT3
SC2
SD2
DESCRIPTION/ORDERING INFORMATION
The PCA9545A is a quad bidirectional translating switch controlled via the I2C bus. The SCL/SDA upstream pair
fans out to four downstream pairs, or channels. Any individual SCn/SDn channel or combination of channels can
be selected, determined by the contents of the programmable control register. Four interrupt inputs (INT3–INT0),
one for each of the downstream pairs, are provided. One interrupt (INT) output acts as an AND of the four
interrupt inputs.
An active-low reset (RESET) input allows the PCA9545A to recover from a situation in which one of the
downstream I2C buses is stuck in a low state. Pulling RESET low resets the I2C state machine and causes all
the channels to be deselected, as does the internal power-on reset function.
The pass gates of the switches are constructed such that the VCC pin can be used to limit the maximum high
voltage, which will be passed by the PCA9545A. This allows the use of different bus voltages on each pair, so
that 1.8-V, 2.5-V, or 3.3-V parts can communicate with 5-V parts, without any additional protection. External
pullup resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5.5-V tolerant.
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas
Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.
PRODUCTION DATA information is current as of publication date.
Products conform to specifications per the terms of the Texas
Instruments standard warranty. Production processing does not
necessarily include testing of all parameters.
Copyright © 2005–2006, Texas Instruments Incorporated
PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
DESCRIPTION/ORDERING INFORMATION (CONTINUED)
ORDERING INFORMATION
PACKAGE (1)
TA
Reel of 3000
PCA9545ARGWR
PD545A
QFN – RGY
Reel of 1000
PCA9545ARGYR
PD545A
Tube of 25
PCA9545ADW
Reel of 2000
PCA9545ADWR
Reel of 250
PCA9545ADWT
PCA9545A
PCA9545APW
PD545A
Tube of 70
TSSOP – PW
Reel of 2000
Reel of 250
PCA9545APWE4
PCA9545APWR
PD545A
PCA9545APWRE4
PCA9545APWT
PD545A
PCA9545APWTE4
PCA9545ADGVR
Reel of 250
PCA9545ADGVT
VFBGA – GQN
Reel of 1000
PCA9545AGQNR
PD545A
VFBGA – ZQN (Pb-free)
Reel of 1000
PCA9545AZQNR
PD545A
PD545A
Package drawings, standard packing quantities, thermal data, symbolization, and PCB design guidelines are available at
www.ti.com/sc/package.
GQN OR ZQN PACKAGE
(TOP VIEW)
TERMINAL ASSIGNMENTS
1
2
3
4
A
A1
A0
VCC
SDA
A
B
INT0
INT
RESET
SCL
B
C
SC0
SD0
SD3
SC3
C
D
SD1
SC2
INT1
INT3
D
E
GND
SC1
INT2
SD2
1
2
3
4
E
2
PCA9545A
Reel of 2000
TVSOP – DGV
(1)
TOP-SIDE MARKING
QFN – RGW
SOIC – DW
–40°C to 85°C
ORDERABLE PART NUMBER
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PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
TERMINAL FUNCTIONS
NO.
DGV, DW, PW,
AND RGY
RGW
GQN AND
ZQN
NAME
DESCRIPTION
1
19
A2
A0
Address input 0. Connect directly to VCC or ground.
2
20
A1
A1
Address input 1. Connect directly to VCC or ground.
3
1
B3
RESET
4
2
B1
INT0
Active-low interrupt input 0. Connect to VCC through a
pullup resistor.
5
3
C2
SD0
Serial data 0. Connect to VCC through a pullup resistor.
6
4
C1
SC0
Serial clock 0. Connect to VCC through a pullup resistor.
7
5
D3
INT1
Active-low interrupt input 1. Connect to VCC through a
pullup resistor.
8
6
D1
SD1
Serial data 1. Connect to VCC through a pullup resistor.
9
7
E2
SC1
Serial clock 1. Connect to VCC through a pullup resistor.
10
8
E1
GND
Ground
11
9
E3
INT2
Active-low interrupt input 2. Connect to VCC through a
pullup resistor.
12
10
E4
SD2
Serial data 2. Connect to VCC through a pullup resistor.
13
11
D2
SC2
Serial clock 2. Connect to VCC through a pullup resistor.
14
12
D4
INT3
Active-low interrupt input 3. Connect to VCC through a
pullup resistor.
15
13
C3
SD3
Serial data 3. Connect to VCC through a pullup resistor.
16
14
C4
SC3
Serial clock 3. Connect to VCC through a pullup resistor.
17
15
B2
INT
Active-low interrupt output. Connect to VCC through a pullup
resistor.
18
16
B4
SCL
Serial clock line. Connect to VCC through a pullup resistor.
19
17
A4
SDA
Serial data line. Connect to VCC through a pullup resistor.
20
18
A3
VCC
Supply power
Active-low reset input. Connect to VCC through a pullup
resistor, if not used.
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PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
BLOCK DIAGRAM
PCA9545A
SC0
SC1
SC2
SC3
6
9
13
16
SD0
5
SD1
8
SD2 12
SD3 15
GND
VCC
RESET
Switch Control Logic
10
20
3
Power-on Reset
SCL 18
SDA
INT0
INT1
19
1
Input Filter
I2C Bus Control
A0
A1
4
7
Interrupt Logic
INT2 11
INT3 14
Pin numbers shown are for DGV, DW, PW, and RGY packages.
4
2
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Output
Filter
17
INT
PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Device Address
Following a start condition, the bus master must output the address of the slave it is accessing. The address of
the PCA9545A is shown in Figure 1. To conserve power, no internal pullup resistors are incorporated on the
hardware-selectable address pins, and they must be pulled high or low.
Slave Address
1
1
0
1
0
A1
A0 R/W
Hardware
Selectable
Fixed
Figure 1. PCA9545A Address
The last bit of the slave address defines the operation to be performed. When set to a logic 1, a read is selected,
while a logic 0 selects a write operation.
Control Register
Following the successful acknowledgment of the slave address, the bus master sends a byte to the PCA9545A,
which is stored in the control register (see Figure 2). If multiple bytes are received by the PCA9545A, it saves
the last byte received. This register can be written and read via the I2C bus.
Interrupt Bits
(Read Only)
7
6
5
Channel-Selection Bits
(Read/Write)
4
INT3 INT2 INT1 INT0
3
2
1
0
B3
B2
B1
B0
Channel 0
Channel 1
Channel 2
Channel 3
INT0
INT1
INT2
INT3
Figure 2. Control Register
Control Register Definition
One or several SCn/SDn downstream pairs, or channels, are selected by the contents of the control register
(see Table 1). After the PCA9545A has been addressed, the control register is written. The four LSBs of the
control byte are used to determine which channel or channels are to be selected. When a channel is selected,
the channel becomes active after a stop condition has been placed on the I2C bus. This ensures that all
SCn/SDn lines are in a high state when the channel is made active, so that no false conditions are generated at
the time of connection. A stop condition must occur always right after the acknowledge cycle.
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PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Table 1. Control Register Write (Channel Selection), Control Register Read (Channel Status) (1)
(1)
INT3
INT2
INT1
INT0
D3
B2
B1
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
0
0
0
0
0
X
1
0
0
Channel 0 disabled
1
Channel 0 enabled
X
X
X
X
X
0
X
0
1
COMMAND
Channel 1 disabled
X
1
0
0
B0
Channel 1 enabled
Channel 2 disabled
Channel 2 enabled
Channel 3 disabled
Channel 3 enabled
No channel selected,
power-up/reset default state
Several channels can be enabled at the same time. For example, B3 = 0, B2 = 1, B1 = 1, B0 = 0 means that channels 0 and 3 are
disabled, and channels 1 are 2 and enabled. Care should be taken not to exceed the maximum bus capacity.
Interrupt Handling
The PCA9545A provides four interrupt inputs (one for each channel) and one open-drain interrupt output (see
Table 2). When an interrupt is generated by any device, it is detected by the PCA9545A and the interrupt output
is driven low. The channel does not need to be active for detection of the interrupt. A bit also is set in the control
register.
Bits 4–7 of the control register correspond to channels 0–3 of the PCA9545A, respectively. Therefore, if an
interrupt is generated by any device connected to channel 1, the state of the interrupt inputs is loaded into the
control register when a read is accomplished. Likewise, an interrupt on any device connected to channel 0 would
cause bit 4 of the control register to be set on the read. The master then can address the PCA9545A and read
the contents of the control register to determine which channel contains the device generating the interrupt. The
master then can reconfigure the PCA9545A to select this channel and locate the device generating the interrupt
and clear it.
It should be noted that more than one device can provide an interrupt on a channel, so it is up to the master to
ensure that all devices on a channel are interrogated for an interrupt.
The interrupt inputs can be used as general-purpose inputs if the interrupt function is not required.
If unused, interrupt input(s) must be connected to VCC.
Table 2. Control Register Read (Interrupt) (1)
INT3
INT2
INT1
X
X
X
X
X
0
1
(1)
6
X
0
1
X
D3
B2
B1
B0
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
0
1
INT0
0
1
COMMAND
No interrupt on channel 0
Interrupt on channel 0
No interrupt on channel 1
Interrupt on channel 1
No interrupt on channel 2
Interrupt on channel 2
No interrupt on channel 3
Interrupt on channel 3
Several interrupts can be active at the same time. For example, INT3 = 0, INT2 = 1, INT1 = 1, INT0 = 0 means that there is no interrupt
on channels 0 and 3, and there is interrupt on channels 1 and 2.
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PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
RESET Input
The RESET input can be used to recover the PCA9545A from a bus-fault condition. The registers and the I2C
state machine within this device initialize to their default states if this signal is asserted low for a minimum of tWL.
All channels also are deselected in this case. RESET must be connected to VCC through a pullup resistor.
Power-On Reset
When power is applied to VCC, an internal power-on reset holds the PCA9545A in a reset condition until VCC has
reached VPOR. At this point, the reset condition is released and the PCA9545A registers and I2C state machine
are initialized to their default states, all zeroes, causing all the channels to be deselected. Thereafter, VCC must
be lowered below 0.2 V to reset the device.
Voltage Translation
The pass-gate transistors of the PCA9545A are constructed such that the VCC voltage can be used to limit the
maximum voltage that is passed from one I2C bus to another.
Figure 3 shows the voltage characteristics of the pass-gate transistors (note that the graph was generated using
data specified in the electrical characteristics section of this data sheet). In order for the PCA9545A to act as a
voltage translator, the Vpass voltage must be equal to or lower than the lowest bus voltage. For example, if the
main bus is running at 5 V and the downstream buses are 3.3 V and 2.7 V, Vpass must be equal to or below 2.7
V to effectively clamp the downstream bus voltages. As shown in Figure 3, Vpass (max) is at 2.7 V when the
PCA9545A supply voltage is 3.5 V or lower, so the PCA9545A supply voltage could be set to 3.3 V. Pullup
resistors then can be used to bring the bus voltages to their appropriate levels (see Figure 13).
5
4.5
Maximum
Vpass (V)
4
Typical
3.5
3
2.5
2
Minimum
1.5
1
2
2.5
3
3.5
4
4.5
5
5.5
VCC (V)
Figure 3. Vpass Voltage vs VCC
I2C Interface
The I2C bus is for two-way two-line communication between different ICs or modules. The two lines are a serial
data line (SDA) and a serial clock line (SCL). Both lines must be connected to a positive supply via a pullup
resistor when connected to the output stages of a device. Data transfer can be initiated only when the bus is not
busy.
One data bit is transferred during each clock pulse. The data on the SDA line must remain stable during the high
period of the clock pulse, as changes in the data line at this time are interpreted as control signals (see
Figure 4).
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PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
SDA
SCL
Data Line
Stable;
Data Valid
Change
of Data
Allowed
Figure 4. Bit Transfer
Both data and clock lines remain high when the bus is not busy. A high-to-low transition of the data line while
the clock is high is defined as the start condition (S). A low-to-high transition of the data line while the clock is
high is defined as the stop condition (P) (see Figure 5).
SDA
SCL
S
P
Start Condition
Stop Condition
Figure 5. Definition of Start and Stop Conditions
A device generating a message is a transmitter; a device receiving a message is the receiver. The device that
controls the message is the master, and the devices that are controlled by the master are the slaves (see
Figure 6).
SDA
SCL
Master
Transmitter/
Receiver
Slave
Receiver
Slave
Transmitter/
Receiver
Master
Transmitter
Master
Transmitter/
Receiver
I2C
Multiplexer
Slave
Figure 6. System Configuration
The number of data bytes transferred between the start and the stop conditions from transmitter to receiver is
not limited. Each byte of eight bits is followed by one acknowlege (ACK) bit. The transmitter must release the
SDA line before the receiver can send an ACK bit.
When a slave receiver is addressed, it must generate an ACK after the reception of each byte. Also, a master
must generate an ACK after the reception of each byte that has been clocked out of the slave transmitter. The
device that acknowledges must pull down the SDA line during the ACK clock pulse so that the SDA line is stable
low during the high pulse of the ACK-related clock period (see Figure 7). Setup and hold times must be taken
into account.
8
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PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Data Output
by Transmitter
NACK
Data Output
by Receiver
ACK
SCL From
Master
1
2
8
9
S
Start
Condition
Clock Pulse for ACK
Figure 7. Acknowledgment on the I2C Bus
A master receiver must signal an end of data to the transmitter by not generating an acknowledge (NACK) after
the last byte has been clocked out of the slave. This is done by the master receiver by holding the SDA line
high. In this event, the transmitter must release the data line to enable the master to generate a stop condition.
Data is transmitted to the PCA9545A control register using the write mode shown in Figure 8.
Slave Address
SDA
S
1
1
1
0
0
Control Register
A1 A0
0
A
X
X
X
X
B3 B2 B1 B0
P
ACK From Slave
R/W ACK From Slave
Start Condition
A
Stop Condition
Figure 8. Write Control Register
Data is read from the PCA9545A control register using the read mode shown in Figure 9.
Slave Address
SDA
S
1
Start Condition
1
1
0
0
Control Register
A1
A0
1
R/W
A INT3 INT2 INT1 INT0 B3
ACK From Slave
B2
B1
B0
NA
NACK From Master
P
Stop Condition
Figure 9. Read Control Register
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PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Absolute Maximum Ratings (1)
over operating free-air temperature range (unless otherwise noted)
MIN
MAX
VCC
Supply voltage range
–0.5
7
V
VI
Input voltage range (2)
–0.5
7
V
II
Input current
±20
mA
IO
Output current
±25
mA
±100
mA
±100
mA
Continuous current through VCC
Continuous current through GND
θJA
Package thermal impedance (3)
DGV package
92
DW package
58
GQN/ZQN package
78
PW package
83
RGW package
TBD
RGY package
47
UNIT
°C/W
Ptot
Total power dissipation
400
mW
Tstg
Storage temperature range
–65
150
°C
TA
Operating free-air temperature range
–40
85
°C
(1)
(2)
(3)
Stresses beyond those listed under "absolute maximum ratings" may cause permanent damage to the device. These are stress ratings
only, and functional operation of the device at these or any other conditions beyond those indicated under "recommended operating
conditions" is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
The input negative-voltage and output voltage ratings may be exceeded if the input and output current ratings are observed.
The package thermal impedance is calculated in accordance with JESD 51-7.
Recommended Operating Conditions (1)
VCC
Supply voltage
VIH
High-level input voltage
VIL
Low-level input voltage
TA
Operating free-air temperature
(1)
10
MIN
MAX
2.3
5.5
SCL, SDA
0.7 × VCC
6
A1, A0, INT3–INT0, RESET
0.7 × VCC
VCC + 0.5
SCL, SDA
–0.5
0.3 × VCC
A1, A0, INT3–INT0, RESET
–0.5
0.3 × VCC
–40
85
UNIT
All unused inputs of the device must be held at VCC or GND to ensure proper device operation. Refer to the TI application report,
Implications of Slow or Floating CMOS Inputs, literature number SCBA004.
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V
V
V
°C
PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Electrical Characteristics
over recommended operating free-air temperature range (unless otherwise noted)
PARAMETER
VPOR
Power-on reset
TEST CONDITIONS
voltage (2)
No load,
VI = VCC or GND
VCC
MIN TYP (1)
MAX
VPOR
1.6
2.1
5V
3.6
4.5 V to 5.5 V
Vpass
Switch output voltage
VSWin = VCC,
ISWout = –100 µA
2.6
3.3 V
3 V to 3.6 V
IOH
INT
VO = VCC
1.6
VOL = 0.6 V
INT
2.8
2.3 V to 5.5 V
VOL = 0.4 V
2
10
3
7
6
10
A1, A0
±1
VI = VCC or GND
±1
2.3 V to 5.5 V
±1
RESET
Operating mode fSCL = 100 kHz
Low inputs
VI = VCC or GND, IO = 0
VI = GND,
IO = 0
Standby mode
High inputs
INT3–INT0
Supply-current
change
SCL, SDA
VI = VCC,
IO = 0
5.5 V
3
12
3.6 V
3
11
2.7 V
3
10
5.5 V
0.3
1
3.6 V
0.1
1
2.7 V
0.1
1
5.5 V
0.3
1
3.6 V
0.1
1
2.7 V
0.1
1
8
15
8
15
8
15
8
15
4.5
6
One INT3–INT0 input at 0.6 V,
Other inputs at VCC or GND
One INT3–INT0 input at VCC – 0.6 V,
Other inputs at VCC or GND
SCL or SDA input at 0.6 V,
Other inputs at VCC or GND
INT3–INT0
SCL or SDA input at VCC – 0.6 V,
Other inputs at VCC or GND
VI = VCC or GND
2.3 V to 5.5 V
RESET
Cio(OFF) (3)
RON
(1)
(2)
(3)
SCL, SDA
SC3–SC0, SD3–SD0
Switch on-state resistance
VI = VCC or GND, Switch OFF
VO = 0.4 V,
IO = 15 mA
VO = 0.4 V,
IO = 10 mA
µA
µA
2.3 V to 5.5 V
A1, A0
Ci
µA
±1
INT3–INT0
∆ICC
mA
±1
SC3–SC0, SD3–SD0
ICC
µA
3
SCL, SDA
II
V
1.5
1.1
2.3 V to 5.5 V
VOL = 0.4 V
SCL, SDA
IOL
V
4.5
1.9
2.5 V
2.3 V to 2.7 V
UNIT
2.3 V to 5.5 V
4.5
6
4.5
5.5
15
19
6
8
4.5 V to 5.5 V
4
9
16
3 V to 3.6 V
5
11
20
2.3 V to 2.7 V
7
16
45
pF
pF
Ω
All typical values are at nominal supply voltage (2.5-V, 3.3-V, or 5-V VCC), TA = 25°C.
The power-on reset circuit resets the I2C bus logic with VCC < VPOR. VCC must be lowered to 0.2 V to reset the device.
Cio(ON) depends on the device capacitance and load that is downstream from the device.
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PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
I2C Interface Timing Requirements
over recommended operating free-air temperature range (unless otherwise noted) (see Figure 10)
STANDARD MODE
I2C BUS
MIN
MAX
100
FAST MODE
I2C BUS
UNIT
MIN
MAX
0
400
fscl
I2C clock frequency
0
tsch
I2C clock high time
4
0.6
µs
tscl
I2C clock low time
4.7
1.3
µs
tsp
I2C
tsds
I2C serial-data setup time
250
100
ns
tsdh
I2C serial-data hold time
0 (1)
0 (1)
µs
ticr
I2C input rise time
ticf
I2C
tocf
I2C output fall time
tbuf
I2C bus free time between stop and start
4.7
1.3
µs
tsts
I2C start or repeated start condition setup
4.7
0.6
µs
tsth
I2C start or repeated start condition hold
4
0.6
µs
tsps
I2C stop condition setup
4
0.6
µs
tvdL(Data)
Valid-data time (high to low) (3)
SCL low to SDA output low
valid
tvdH(Data)
Valid-data time (low to high) (3)
SCL low to SDA output high
valid
tvd(ack)
Valid-data time of ACK condition
ACK signal from SCL low
to SDA output low
Cb
I2C bus capacitive load
(1)
(2)
(3)
spike time
50
input fall time
10-pF to 400-pF bus
50
kHz
ns
1000
20 + 0.1Cb (2)
300
ns
300
20 + 0.1Cb
(2)
300
ns
300
20 + 0.1Cb (2)
300
ns
1
1
µs
0.6
0.6
µs
1
1
µs
400
400
pF
A device internally must provide a hold time of at least 300 ns for the SDA signal (referred to as the VIH min of the SCL signal), in order
to bridge the undefined region of the falling edge of SCL.
Cb = total bus capacitance of one bus line in pF
Data taken using a 1-kΩ pullup resistor and 50-pF load (see Figure 10)
Switching Characteristics
over recommended operating free-air temperature range, CL ≤ 100 pF (unless otherwise noted) (see Figure 12)
PARAMETER
tpd (1)
Propagation delay time
tiv
Interrupt valid time (2)
tir
(1)
(2)
12
Interrupt reset delay
time (2)
RON = 20 Ω, CL = 15 pF
RON = 20 Ω, CL = 50 pF
FROM
(INPUT)
TO
(OUTPUT)
SDA or SCL
SDn or SCn
INTn
INT
4
µs
INTn
INT
2
µs
MIN
MAX
0.3
1
The propagation delay is the calculated RC time constant of the typical ON-state resistance of the switch and the specified load
capacitance, when driven by an ideal voltage source (zero output impedance).
Data taken using a 4.7-kΩ pullup resistor and 100-pF load (see Figure 12)
Submit Documentation Feedback
UNIT
ns
PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
Interrupt and Reset Timing Requirements
over recommended operating free-air temperature range (unless otherwise noted) (see Figure 12)
PARAMETER
MIN
tPWRL
Low-level pulse duration rejection of INTn inputs
1
µs
tPWRH
High-level pulse duration rejection of INTn inputs
0.5
µs
tWL
Pulse duration, RESET low
trst (1)
RESET time (SDA clear)
tREC(STA)
Recovery time from RESET to start
(1)
MAX
UNIT
6
ns
500
0
ns
ns
trst is the propagation delay measured from the time the RESET pin is first asserted low to the time the SDA pin is asserted high,
signaling a stop condition. It must be a minimum of tWL.
Submit Documentation Feedback
13
PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
PARAMETER MEASUREMENT INFORMATION
VCC
RL = 1 kΩ
SDn, SCn
DUT
CL = 50 pF
(See Note A)
I2C PORT LOAD CONFIGURATION
Two Bytes for Complete
Device Programming
Address
Stop
Start
Address
Bit 7
Condition Condition
Bit 6
(MSB)
(P)
(S)
BYTE
Address
Bit 1
R/W
Bit 0
(LSB)
ACK
(A)
Data
Bit 7
(MSB)
Data
Bit 0
(LSB)
ACK
(A)
Stop
Condition
(P)
DESCRIPTION
I2C
1
2
address + R/W
Control register data
tscl
tsch
0.7 × VCC
SCL
tvd(ACK)
or tvdL
tvdH
ticr
ticf
tbuf
tsp
0.3 × VCC
tsts
0.7 × VCC
SDA
0.3 × VCC
ticr
ticf
tsth
tsdh
tsds
tsps
Repeat
Start
Condition
Start or Repeat
Start Condition
Stop
Condition
VOLTAGE WAVEFORMS
A.
CL includes probe and jig capacitance.
B.
All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, ZO = 50 Ω,
tr/tf = 30 ns.
C.
The outputs are measured one at a time, with one transition per measurement.
Figure 10. I2C Interface Load Circuit, Byte Descriptions, and Voltage Waveforms
14
Submit Documentation Feedback
PCA9545A
4-CHANNEL
AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
I2C
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
PARAMETER MEASUREMENT INFORMATION (continued)
Start
ACK or Read Cycle
SCL
SDA
30%
trst
50%
RESET
tREC
tWL
trst
50%
LEDx
LED OFF
Figure 11. Reset Timing
VCC
RL = 4.7 kΩ
DUT
INT
CL = 100 pF
(See Note A)
INTERRUPT LOAD CONFIGURATION
INTn
(input)
0.5 × VCC
INTn
(input)
tiv
INT
(output)
0.5 × VCC
tir
0.5 × VCC
INT
(output)
VOLTAGE WAVEFORMS (tiv)
0.5 × VCC
VOLTAGE WAVEFORMS (tir)
A.
CL includes probe and jig capacitance.
B.
All input pulses are supplied by generators having the following characteristics: PRR ≤ 10 MHz, ZO = 50 Ω,
tr/tf = 30 ns.
Figure 12. Interrupt Load Circuit and Voltage Waveforms
Submit Documentation Feedback
15
PCA9545A
4-CHANNEL I2C AND SMBus SWITCH
WITH INTERRUPT LOGIC AND RESET FUNCTIONS
www.ti.com
SCPS147C – OCTOBER 2005 – REVISED OCTOBER 2006
APPLICATION INFORMATION
Figure 13 shows an application in which the PCA9545A can be used.
VCC = 2.7 V to 5.5 V
VCC = 3.3 V
VCC = 2.7 V to 5.5 V
20
SDA
I2C/SMBus
SCL
Master
19
18
17
3
See Note A
SDA
SD0
SCL
SC0
INT
RESET
INT0
5
6
4
Channel 0
VCC = 2.7 V to 5.5 V
See Note A
SD1
8
SC1
9
7
INT1
Channel 1
VCC = 2.7 V to 5.5 V
PCA9545A
See Note A
SD2
SC2
INT2
2
1
10
A1
A0
GND
12
13
VCC = 2.7 V to 5.5 V
See Note A
SD3
SC3
INT3
15
16
Channel 3
14
A.
If the device generating the interrupt has an open-drain output structure or can be 3-stated, a pullup resistor is
required. If the device generating the interrupt has a totem-pole output structure and cannot be 3-stated, a pullup
resistor is not required. The interrupt inputs should not be left floating.
B.
Pin numbers shown are for DGV, DW, PW, and RGY packages.
Figure 13. Typical Application
16
Channel 2
11
Submit Documentation Feedback
PACKAGE OPTION ADDENDUM
www.ti.com
30-Mar-2007
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
PCA9545ADGVR
ACTIVE
TVSOP
DGV
20
2000 Green (RoHS &
no Sb/Br)
PCA9545ADGVT
PREVIEW
TVSOP
DGV
20
250
TBD
Call TI
PCA9545ADW
ACTIVE
SOIC
DW
20
25
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545ADWR
ACTIVE
SOIC
DW
20
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545ADWT
PREVIEW
SOIC
DW
20
250
TBD
Call TI
Call TI
PCA9545AGQNR
NRND
GQN
20
1000
TBD
SNPB
Level-1-240C-UNLIM
PCA9545APW
ACTIVE
TSSOP
PW
20
70
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545APWE4
ACTIVE
TSSOP
PW
20
70
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545APWR
ACTIVE
TSSOP
PW
20
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545APWRE4
ACTIVE
TSSOP
PW
20
2000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545APWT
ACTIVE
TSSOP
PW
20
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545APWTE4
ACTIVE
TSSOP
PW
20
250
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-1-260C-UNLIM
PCA9545ARGWR
PREVIEW
QFN
RGW
20
3000
TBD
Call TI
PCA9545ARGYR
ACTIVE
QFN
RGY
20
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1YEAR
PCA9545ARGYRG4
ACTIVE
QFN
RGY
20
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-2-260C-1YEAR
PCA9545AZQNR
ACTIVE
ZQN
20
1000 Green (RoHS &
no Sb/Br)
SNAGCU
Level-1-260C-UNLIM
BGA MI
CROSTA
R JUNI
OR
BGA MI
CROSTA
R JUNI
OR
Pins Package Eco Plan (2)
Qty
Lead/Ball Finish
CU NIPDAU
MSL Peak Temp (3)
Level-1-260C-UNLIM
Call TI
Call TI
(1)
The marketing status values are defined as follows:
ACTIVE: Product device recommended for new designs.
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in
a new design.
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.
OBSOLETE: TI has discontinued the production of the device.
(2)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
Addendum-Page 1
PACKAGE OPTION ADDENDUM
www.ti.com
30-Mar-2007
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited
information may not be available for release.
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI
to Customer on an annual basis.
Addendum-Page 2
MECHANICAL DATA
MPDS006C – FEBRUARY 1996 – REVISED AUGUST 2000
DGV (R-PDSO-G**)
PLASTIC SMALL-OUTLINE
24 PINS SHOWN
0,40
0,23
0,13
24
13
0,07 M
0,16 NOM
4,50
4,30
6,60
6,20
Gage Plane
0,25
0°–8°
1
0,75
0,50
12
A
Seating Plane
0,15
0,05
1,20 MAX
PINS **
0,08
14
16
20
24
38
48
56
A MAX
3,70
3,70
5,10
5,10
7,90
9,80
11,40
A MIN
3,50
3,50
4,90
4,90
7,70
9,60
11,20
DIM
4073251/E 08/00
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion, not to exceed 0,15 per side.
Falls within JEDEC: 24/48 Pins – MO-153
14/16/20/56 Pins – MO-194
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
MECHANICAL DATA
MTSS001C – JANUARY 1995 – REVISED FEBRUARY 1999
PW (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
14 PINS SHOWN
0,30
0,19
0,65
14
0,10 M
8
0,15 NOM
4,50
4,30
6,60
6,20
Gage Plane
0,25
1
7
0°– 8°
A
0,75
0,50
Seating Plane
0,15
0,05
1,20 MAX
PINS **
0,10
8
14
16
20
24
28
A MAX
3,10
5,10
5,10
6,60
7,90
9,80
A MIN
2,90
4,90
4,90
6,40
7,70
9,60
DIM
4040064/F 01/97
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Body dimensions do not include mold flash or protrusion not to exceed 0,15.
Falls within JEDEC MO-153
POST OFFICE BOX 655303
• DALLAS, TEXAS 75265
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