View PCA9545A_4739361.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
Rev. 07 -- 19 June 2009 Product data sheet
1. General description
The PCA9545A/45B/45C 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 SCx/SDx channel or combination of channels can be selected, determined by the contents of the programmable control register. Four interrupt inputs, INT0 to INT3, one for each of the downstream pairs, are provided. One interrupt output, INT, acts as an AND of the four interrupt inputs. An active LOW reset input allows the PCA9545A/45B/45C to recover from a situation where one of the downstream I2C-buses is stuck in a LOW state. Pulling the RESET pin LOW resets the I2C-bus 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 VDD pin can be used to limit the maximum high voltage which will be passed by the PCA9545A/45B/45C. This allows the use of different bus voltages on each pair, so that 1.8 V or 2.5 V or 3.3 V parts can communicate with 5 V parts without any additional protection. External pull-up resistors pull the bus up to the desired voltage level for each channel. All I/O pins are 5 V tolerant. The PCA9545A, PCA9545B and PCA9545C are identical except for the fixed portion of the slave address.
2. Features
I I I I I I I I I I I I I I I 1-of-4 bidirectional translating switches I2C-bus interface logic; compatible with SMBus standards 4 active LOW interrupt inputs Active LOW interrupt output Active LOW reset input 2 address pins allowing up to 4 devices on the I2C-bus Alternate address versions A, B and C allow up to a total of 12 devices on the bus for larger systems or to resolve address conflicts 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 No glitch on power-up Supports hot insertion Low standby current Operating power supply voltage range of 2.3 V to 5.5 V
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
I 5 V tolerant Inputs I 0 Hz to 400 kHz clock frequency I ESD protection exceeds 2000 V HBM per JESD22-A114, 200 V MM per JESD22-A115, and 1000 V CDM per JESD22-C101 I Latch-up protection exceeds 100 mA per JESD78 I Three packages offered: SO20, TSSOP20, and HVQFN20
3. Ordering information
Table 1. Ordering information Package Name PCA9545ABS PCA9545AD PCA9545APW PCA9545BPW PCA9545CPW HVQFN20 SO20 TSSOP20 Description Version plastic thermal enhanced very thin quad flat package; SOT662-1 no leads; 20 terminals; body 5 x 5 x 0.85 mm plastic small outline package; 20 leads; body width 7.5 mm plastic thin shrink small outline package; 20 leads; body width 4.4 mm SOT163-1 SOT360-1 Type number
3.1 Ordering options
Table 2. Ordering options Topside mark 9545A PCA9545AD PA9545A PA9545B PA9545C Temperature range -40 C to +85 C -40 C to +85 C -40 C to +85 C -40 C to +85 C -40 C to +85 C Type number PCA9545ABS PCA9545AD PCA9545APW PCA9545BPW PCA9545CPW
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
2 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
4. Block diagram
PCA9545A/PCA9545B/PCA9545C
SC0 SC1 SC2 SC3 SD0 SD1 SD2 SD3
VSS VDD RESET
SWITCH CONTROL LOGIC
POWER-ON RESET
SCL SDA
INPUT FILTER
I2C-BUS CONTROL
A0 A1
INT0 to INT3
INTERRUPT LOGIC
INT
002aab168
Fig 1.
Block diagram of PCA9545A/45B/45C
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
3 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
5. Pinning information
5.1 Pinning
A0 A1 RESET INT0 SD0 SC0 INT1 SD1 SC1
1 2 3 4 5 6 7 8 9
20 VDD 19 SDA 18 SCL 17 INT 16 SC3 15 SD3 14 INT3 13 SC2 12 SD2 11 INT2
002aab165
A0 A1 RESET INT0 SD0 SC0 INT1 SD1 SC1
1 2 3 4 5 6 7 8 9
20 VDD 19 SDA 18 SCL 17 INT
PCA9545AD
PCA9545APW PCA9545BPW PCA9545CPW
16 SC3 15 SD3 14 INT3 13 SC2 12 SD2 11 INT2
VSS 10
VSS 10
002aab166
Fig 2.
Pin configuration for SO20
20 A1 19 A0 terminal 1 index area
Fig 3.
17 SDA 16 SCL 18 VDD
Pin configuration for TSSOP20
RESET INT0 SD0 SC0 INT1
1 2 3 4 5 SD2 10 6 7 8 9
15 INT 14 SC3
PCA9545ABS
13 SD3 12 INT3 11 SC2
VSS
INT2
SD1
SC1
002aab167
Transparent top view
Fig 4.
Pin configuration for HVQFN20 (transparent top view)
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
4 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
5.2 Pin description
Table 3. Symbol A0 A1 RESET INT0 SD0 SC0 INT1 SD1 SC1 VSS INT2 SD2 SC2 INT3 SD3 SC3 INT SCL SDA VDD
[1]
Pin description Pin SO20, TSSOP20 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 HVQFN20 19 20 1 2 3 4 5 6 7 8[1] 9 10 11 12 13 14 15 16 17 18 address input 0 address input 1 active LOW reset input active LOW interrupt input 0 serial data 0 serial clock 0 active LOW interrupt input 1 serial data 1 serial clock 1 supply ground active LOW interrupt input 2 serial data 2 serial clock 2 active LOW interrupt input 3 serial data 3 serial clock 3 active LOW interrupt output serial clock line serial data line supply voltage Description
HVQFN20 package die supply ground is connected to both the VSS pin and the exposed center pad. The VSS pin must be connected to supply ground for proper device operation. For enhanced thermal, electrical, and board-level performance, the exposed pad needs to be soldered to the board using a corresponding thermal pad on the board, and for proper heat conduction through the board thermal vias need to be incorporated in the PCB in the thermal pad region.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
5 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
6. Functional description
Refer to Figure 1 "Block diagram of PCA9545A/45B/45C".
6.1 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 5. To conserve power, no internal pull-up resistors are incorporated on the hardware selectable address pins and they must be pulled HIGH or LOW.
1
1
1 fixed
0
0
A1
A0 R/W
hardware selectable
002aab169
Fig 5.
Slave address PCA9545A
The last bit of the slave address defines the operation to be performed. When set to logic 1, a read is selected while a logic 0 selects a write operation. The PCA9545BPW and PCA9545CPW are alternate address versions if needed for larger systems or to resolve conflicts. The data sheet will reference the PCA9545A, but the PCA9545B and PCA9545C function identically except for the slave address.
1
1
0 fixed
1
0
A1
A0 R/W
1
0
1 fixed
1
0
A1
A0 R/W
hardware selectable
002aab835
hardware selectable
002aab836
Fig 6.
Slave address PCA9545B
Fig 7.
Slave address PCA9545C
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
6 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
6.2 Control register
Following the successful acknowledgement of the slave address, the bus master will send a byte to the PCA9545A/45B/45C, which will be stored in the control register. If multiple bytes are received by the PCA9545A/45B/45C, it will save the last byte received. This register can be written and read via the I2C-bus.
interrupt bits (read only) 7 6 5 4 INT INT INT INT 3 2 1 0 3 B3
channel selection bits (read/write) 2 B2 1 B1 0 B0 channel 0 channel 1 channel 2 channel 3 INT0 INT1 INT2 INT3
002aab170
Fig 8.
Control register
6.2.1 Control register definition
One or several SCx/SDx downstream pair, or channel, is selected by the contents of the control register. This register is written after the PCA9545A/45B/45C has been addressed. The 4 LSBs of the control byte are used to determine which channel is to be selected. When a channel is selected, the channel will become active after a STOP condition has been placed on the I2C-bus. This ensures that all SCx/SDx lines will be in a HIGH state when the channel is made active, so that no false conditions are generated at the time of connection.
Table 4. INT3 X X X X 0 Control register: write (channel selection); read (channel status) INT2 X X X X 0 INT1 X X X X 0 INT0 X X X X 0 B3 X X X 0 1 0 B2 X X 0 1 X 0 B1 X 0 1 X X 0 B0 0 1 X X X 0 Command channel 0 disabled channel 0 enabled channel 1 disabled channel 1 enabled channel 2 disabled channel 2 enabled channel 3 disabled channel 3 enabled no channel selected; power-up/reset default state
Remark: Several channels can be enabled at the same time. Example: B3 = 0, B2 = 1, B1 = 1, B0 = 0, means that channel 0 and channel 3 are disabled and channel 1 and channel 2 are enabled. Care should be taken not to exceed the maximum bus capacity.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
7 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
6.2.2 Interrupt handling
The PCA9545A/45B/45C provides 4 interrupt inputs, one for each channel, and one open-drain interrupt output. When an interrupt is generated by any device, it will be detected by the PCA9545A/45B/45C and the interrupt output will be driven LOW. The channel does not need to be active for detection of the interrupt. A bit is also set in the control register. Bit 4 through bit 7 of the control register corresponds to channel 0 through channel 3 of the PCA9545A/45B/45C, 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 can then address the PCA9545A/45B/45C and read the contents of the control register to determine which channel contains the device generating the interrupt. The master can then reconfigure the PCA9545A/45B/45C 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 may be used as general purpose inputs if the interrupt function is not required. If unused, interrupt input(s) must be connected to VDD through a pull-up resistor.
Table 5. INT3 X X X 0 1 Control register: Read--interrupt INT2 X X 0 1 X INT1 X 0 1 X X INT0 0 1 X X X B3 X X X X B2 X X X X B1 X X X X B0 X X X X 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
Remark: Several interrupts can be active at the same time. Example: INT3 = 0, INT2 = 1, INT1 = 1, INT0 = 0, means that there is no interrupt on channel 0 and channel 3, and there is interrupt on channel 1 and channel 2.
6.3 RESET input
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 tw(rst)L, the PCA9545A/45B/45C will reset its registers and I2C-bus state machine and will deselect all channels. The RESET input must be connected to VDD through a pull-up resistor.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
8 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
6.4 Power-on reset
When power is applied to VDD, an internal Power-On Reset (POR) holds the PCA9545A/45B/45C in a reset condition until VDD has reached VPOR. At this point, the reset condition is released and the PCA9545A/45B/45C registers and I2C-bus state machine are initialized to their default states (all zeroes) causing all the channels to be deselected. Thereafter, VDD must be lowered below 0.2 V to reset the device.
6.5 Voltage translation
The pass gate transistors of the PCA9545A/45B/45C are constructed such that the VDD voltage can be used to limit the maximum voltage that will be passed from one I2C-bus to another.
5.0 Vo(sw) (V) 4.0
(1)
002aaa964
3.0
(2) (3)
2.0
1.0 2.0
2.5
3.0
3.5
4.0
4.5
5.5 5.0 VDD (V)
(1) maximum (2) typical (3) minimum
Fig 9.
Pass gate voltage versus supply voltage
Figure 9 shows the voltage characteristics of the pass gate transistors (note that the graph was generated using the data specified in Section 10 "Static characteristics" of this data sheet). In order for the PCA9545A/45B/45C to act as a voltage translator, the Vo(sw) voltage 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 Vo(sw) should be equal to or below 2.7 V to effectively clamp the downstream bus voltages. Looking at Figure 9, we see that Vo(sw)(max) will be at 2.7 V when the PCA9545A/45B/45C supply voltage is 3.5 V or lower, so the PCA9545A/45B/45C 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 Figure 16). More Information can be found in Application Note AN262: PCA954X family of I2C/SMBus multiplexers and switches.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
9 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
7. Characteristics of the I2C-bus
The I2C-bus is for 2-way, 2-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 pull-up resistor when connected to the output stages of a device. Data transfer may be initiated only when the bus is not busy.
7.1 Bit transfer
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 will be interpreted as control signals (see Figure 10).
SDA
SCL data line stable; data valid change of data allowed
mba607
Fig 10. Bit transfer
7.2 START and STOP conditions
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 11).
SDA
SCL S START condition P STOP condition
mba608
Fig 11. Definition of START and STOP conditions
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
10 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
7.3 System configuration
A device generating a message is a `transmitter', a device receiving is the `receiver'. The device that controls the message is the `master' and the devices which are controlled by the master are the `slaves' (see Figure 12).
SDA SCL MASTER TRANSMITTER/ RECEIVER SLAVE RECEIVER SLAVE TRANSMITTER/ RECEIVER MASTER TRANSMITTER MASTER TRANSMITTER/ RECEIVER I2C-BUS MULTIPLEXER
SLAVE
002aaa966
Fig 12. System configuration
7.4 Acknowledge
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 acknowledge bit. The acknowledge bit is a HIGH level put on the bus by the transmitter, whereas the master generates an extra acknowledge related clock pulse. A slave receiver which is addressed must generate an acknowledge after the reception of each byte. Also a master must generate an acknowledge after the reception of each byte that has been clocked out of the slave transmitter. The device that acknowledges has to pull down the SDA line during the acknowledge clock pulse, so that the SDA line is stable LOW during the HIGH period of the acknowledge related clock pulse; set-up and hold times must be taken into account. A master receiver must signal an end of data to the transmitter by not generating an acknowledge on the last byte that has been clocked out of the slave. In this event, the transmitter must leave the data line HIGH to enable the master to generate a STOP condition.
data output by transmitter not acknowledge data output by receiver acknowledge SCL from master S START condition 1 2 8 clock pulse for acknowledgement
002aaa987
9
Fig 13. Acknowledgement on the I2C-bus
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
11 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
7.5 Bus transactions
Data is transmitted to the PCA9545A/45B/45C control register using the Write mode as shown in Figure 14.
slave address SDA S 1 1 1 0 0 A1 A0 0 A X X X
control register X B3 B2 B1 B0 A P
START condition
R/W
acknowledge from slave
acknowledge from slave STOP condition
002aab172
Fig 14. Write control register
Data is read from PCA9545A/45B/45C using the Read mode as shown in Figure 15.
slave address SDA S 1 1 1 0 0 A1 A0 1 A
control register INT3 INT2 INT1 INT0 B3 B2 B1
last byte
B0
NA
P
START condition
R/W
acknowledge from slave
no acknowledge from master STOP condition
002aab173
Fig 15. Read control register
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
12 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
8. Application design-in information
VDD = 2.7 V to 5.5 V VDD = 3.3 V V = 2.7 V to 5.5 V see note (1) SDA SCL SDA SCL INT RESET see note (1) I2C-bus/SMBus master SD1 SC1 INT1 V = 2.7 V to 5.5 V channel 1 SD0 SC0 INT0 V = 2.7 V to 5.5 V channel 0
PCA9545A
SD2 SC2 INT2
see note (1) channel 2
V = 2.7 V to 5.5 V see note (1) A1 A0 VSS SD3 SC3 INT3
002aab171
channel 3
(1) If the device generating the interrupt has an open-drain output structure or can be 3-stated, a pull-up resistor is required. If the device generating the interrupt has a totem-pole output structure and cannot be 3-stated, a pull-up resistor is not required. The interrupt inputs should not be left floating.
Fig 16. Typical application
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
13 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
9. Limiting values
Table 6. Limiting values In accordance with the Absolute Maximum Rating System (IEC 60134). Voltages are referenced to VSS (ground = 0 V).[1] Symbol VDD VI II IO IDD ISS Ptot Tstg Tamb
[1]
Parameter supply voltage input voltage input current output current supply current ground supply current total power dissipation storage temperature ambient temperature
Conditions
Min -0.5 -0.5 -60
Max +7.0 +7.0 20 25 100 100 400 +150 +85
Unit V V mA mA mA mA mW C C
operating
-40
The performance capability of a high-performance integrated circuit in conjunction with its thermal environment can create junction temperatures which are detrimental to reliability. The maximum junction temperature of this integrated circuit should not exceed 125 C.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
14 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
10. Static characteristics
Table 7. Static characteristics at VDD = 2.3 V to 3.6 V VSS = 0 V; Tamb = -40 C to +85 C; unless otherwise specified. See Table 8 on page 16 for VDD = 4.5 V to 5.5 V[1]. Symbol Supply VDD IDD Istb VPOR VIL VIH IOL IL Ci VIL VIH ILI Ci Pass gate Ron ON-state resistance VDD = 3.6 V; VO = 0.4 V; IO = 15 mA VDD = 2.3 V to 2.7 V; VO = 0.4 V; IO = 10 mA Vo(sw) switch output voltage Vi(sw) = VDD = 3.3 V; Io(sw) = -100 A Vi(sw) = VDD = 3.0 V to 3.6 V; Io(sw) = -100 A Vi(sw) = VDD = 2.5 V; Io(sw) = -100 A Vi(sw) = VDD = 2.3 V to 2.7 V; Io(sw) = -100 A IL Cio INT output IOL IOH
[1] [2]
Parameter supply voltage supply current standby current power-on reset voltage LOW-level input voltage HIGH-level input voltage LOW-level output current leakage current input capacitance LOW-level input voltage HIGH-level input voltage input leakage current input capacitance
Conditions
Min 2.3
Typ 10 0.1 1.6 7 10 10 1.6 11 16 1.9 1.5 3 -
Max 3.6 30 1 2.1 +0.3VDD 6 +1 13 +0.3VDD VDD + 0.5 +1 3 30 55 2.8 2.0 +1 5 +10
Unit V A A V V V mA mA A pF V V A pF V V V V A pF mA A
Operating mode; VDD = 3.6 V; no load; VI = VDD or VSS; fSCL = 100 kHz Standby mode; VDD = 3.6 V; no load; VI = VDD or VSS no load; VI = VDD or VSS
[2]
-0.5 0.7VDD
Input SCL; input/output SDA
VOL = 0.4 V VOL = 0.6 V VI = VDD or VSS VI = VSS
3 6 -1 -0.5 0.7VDD
Select inputs A0, A1, INT0 to INT3, RESET
pin at VDD or VSS VI = VSS
-1 5 7 1.6 1.1 -1 3 -
leakage current input/output capacitance LOW-level output current HIGH-level output current
VI = VDD or VSS VI = VSS VOL = 0.4 V
For operation between published voltage ranges, refer to the worst-case parameter in both ranges. VDD must be lowered to 0.2 V in order to reset part.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
15 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
Table 8. Static characteristics at VDD = 4.5 V to 5.5 V VSS = 0 V; Tamb = -40 C to +85 C; unless otherwise specified. See Table 7 on page 15 for VDD = 2.3 V to 3.6 V[1]. Symbol Supply VDD IDD supply voltage supply current Operating mode; VDD = 5.5 V; no load; VI = VDD or VSS; fSCL = 100 kHz Standby mode; VDD = 5.5 V; no load; VI = VDD or VSS no load; VI = VDD or VSS
[2]
Parameter
Conditions
Min 4.5 -
Typ 25
Max 5.5 100
Unit V A
Istb VPOR VIL VIH IOL IL Ci VIL VIH ILI Ci Pass gate Ron Vo(sw)
standby current power-on reset voltage LOW-level input voltage HIGH-level input voltage LOW-level output current leakage current input capacitance LOW-level input voltage HIGH-level input voltage input leakage current input capacitance ON-state resistance switch output voltage
-0.5 0.7VDD
0.3 1.7 10 2 9 3.6 3 -
1 2.1 +0.3VDD 6 +1 13 +0.3VDD VDD + 0.5 +1 5 24 4.5 +1 5 +10
A V V V mA mA A pF V V A pF V V A pF mA A
Input SCL; input/output SDA
VOL = 0.4 V VOL = 0.6 V VI = VSS VI = VSS
3 6 -1 -0.5 0.7VDD
Select inputs A0, A1, INT0 to INT3, RESET
VI = VDD or VSS VI = VSS VDD = 4.5 V to 5.5 V; VO = 0.4 V; IO = 15 mA Vi(sw) = VDD = 5.0 V; Io(sw) = -100 A Vi(sw) = VDD = 4.5 V to 5.5 V; Io(sw) = -100 A
-1 4 2.6 -1 3 -
IL Cio INT output IOL IOH
[1] [2]
leakage current input/output capacitance LOW-level output current HIGH-level output current
VI = VDD or VSS VI = VSS VOL = 0.4 V
For operation between published voltage ranges, refer to the worst-case parameter in both ranges. VDD must be lowered to 0.2 V in order to reset part.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
16 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
11. Dynamic characteristics
Table 9. Symbol Dynamic characteristics Parameter Conditions Standard-mode I2C-bus Min tPD fSCL tBUF tHD;STA tLOW tHIGH tSU;STA tSU;STO tHD;DAT tSU;DAT tr tf Cb tSP tVD;DAT tVD;ACK INT tv(INTnN-INTN) valid time from INTn to INT signal td(INTnN-INTN) delay time from INTn to INT inactive tw(rej)L tw(rej)H RESET tw(rst)L trst tREC;STA
[1] [2] [3] [4] [5]
Fast-mode I2C-bus Unit Min 0 1.3 0.6 1.3 0.6 0.6 0.6 0[3] 100 20 + 0.1Cb[4] 20 + 0.1Cb[4] 1 0.5 4 500 0 Max 0.3[1] ns 400 0.9 300 300 400 50 1 0.6 1 4 2 kHz s s s s s s s ns ns ns pF ns s s s s s s s ns ns ns
Max 0.3[1] 100 3.45 1000 300 400 50 1 0.6 1 4 2 -
propagation delay SCL clock frequency bus free time between a STOP and START condition hold time (repeated) START condition LOW period of the SCL clock HIGH period of the SCL clock set-up time for a repeated START condition set-up time for STOP condition data hold time data set-up time rise time of both SDA and SCL signals fall time of both SDA and SCL signals capacitive load for each bus line pulse width of spikes that must be suppressed by the input filter data valid time data valid acknowledge time
from SDA to SDx, or SCL to SCx
0 4.7
[2]
4.0 4.7 4.0 4.7 4.0 0[3] 250 -
HIGH-to-LOW LOW-to-HIGH
[5] [5]
-
LOW-level rejection time HIGH-level rejection time LOW-level reset time reset time recovery time to START condition
INTn inputs INTn inputs
1 0.5 4
SDA clear
500 0
Pass gate propagation delay is calculated from the 20 typical Ron and the 15 pF load capacitance. After this period, the first clock pulse is generated. A device must internally provide a hold time of at least 300 ns for the SDA signal (referred to the VIH(min) of the SCL signal) in order to bridge the undefined region of the falling edge of SCL. Cb = total capacitance of one bus line in pF. Measurements taken with 1 k pull-up resistor and 50 pF load.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
17 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
SDA tBUF tLOW SCL tr tf tHD;STA tSP
tHD;STA P S tHD;DAT tHIGH tSU;DAT Sr
tSU;STA
tSU;STO P
002aaa986
Fig 17. Definition of timing on the I2C-bus
START SCL
ACK or read cycle
SDA 30 % trst
RESET
50 % tREC;STA
50 %
50 % tw(rst)L
002aac549
Fig 18. Definition of RESET timing
protocol
START condition (S) tSU;STA
bit 7 MSB (A7) tLOW tHIGH
bit 6 (A6)
bit 0 (R/W)
acknowledge (A)
STOP condition (P)
1/f
SCL
SCL tBUF tr tf
SDA
tHD;STA
tSU;DAT
tHD;DAT
tVD;DAT
tVD;ACK
tSU;STO
002aab175
Rise and fall times refer to VIL and VIH.
Fig 19. I2C-bus timing diagram
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
18 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
SCL
2
1
0
A
P
70 % 30 %
SDA
INPUT tv(INTnN-INTN) INT
002aab176
50 % td(INTnN-INTN)
Fig 20. Expanded view of read input port register
12. Test information
VDD VDD PULSE GENERATOR VI D.U.T.
RT CL 50 pF RL 500
VO
002aab177
Definitions test circuit: RL = Load resistance. CL = Load capacitance including jig and probe capacitance. RT = Termination resistance should be equal to the output impedance Zo of the pulse generator.
Fig 21. Test circuitry for switching times
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
19 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
13. Package outline
SO20: plastic small outline package; 20 leads; body width 7.5 mm SOT163-1
D
E
A X
c y HE vMA
Z 20 11
Q A2 A1 pin 1 index Lp L 1 e bp 10 wM detail X (A 3) A
0
5 scale
10 mm
DIMENSIONS (inch dimensions are derived from the original mm dimensions) UNIT mm inches A max. 2.65 0.1 A1 0.3 0.1 A2 2.45 2.25 A3 0.25 0.01 bp 0.49 0.36 c 0.32 0.23 D (1) 13.0 12.6 0.51 0.49 E (1) 7.6 7.4 0.30 0.29 e 1.27 0.05 HE 10.65 10.00 L 1.4 Lp 1.1 0.4 Q 1.1 1.0 0.043 0.039 v 0.25 0.01 w 0.25 0.01 y 0.1 Z
(1)
0.9 0.4
0.012 0.096 0.004 0.089
0.019 0.013 0.014 0.009
0.419 0.043 0.055 0.394 0.016
0.035 0.004 0.016
8 o 0
o
Note 1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included. OUTLINE VERSION SOT163-1 REFERENCES IEC 075E04 JEDEC MS-013 JEITA EUROPEAN PROJECTION
ISSUE DATE 99-12-27 03-02-19
Fig 22. Package outline SOT163-1 (SO20)
PCA9545A_45B_45C_7 (c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
20 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
TSSOP20: plastic thin shrink small outline package; 20 leads; body width 4.4 mm
SOT360-1
D
E
A
X
c y HE vMA
Z
20
11
Q A2 pin 1 index A1 (A 3) A
Lp L
1
e bp
10
wM detail X
0
2.5 scale
5 mm
DIMENSIONS (mm are the original dimensions) UNIT mm A max. 1.1 A1 0.15 0.05 A2 0.95 0.80 A3 0.25 bp 0.30 0.19 c 0.2 0.1 D (1) 6.6 6.4 E (2) 4.5 4.3 e 0.65 HE 6.6 6.2 L 1 Lp 0.75 0.50 Q 0.4 0.3 v 0.2 w 0.13 y 0.1 Z (1) 0.5 0.2 8 o 0
o
Notes 1. Plastic or metal protrusions of 0.15 mm maximum per side are not included. 2. Plastic interlead protrusions of 0.25 mm maximum per side are not included. OUTLINE VERSION SOT360-1 REFERENCES IEC JEDEC MO-153 JEITA EUROPEAN PROJECTION ISSUE DATE 99-12-27 03-02-19
Fig 23. Package outline SOT360-1 (TSSOP20)
PCA9545A_45B_45C_7 (c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
21 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
HVQFN20: plastic thermal enhanced very thin quad flat package; no leads; 20 terminals; body 5 x 5 x 0.85 mm
SOT662-1
D
B
A
terminal 1 index area E
A A1 c
detail X
e1 e 6 L 11 b 10 vMCAB wMC y1 C
C y
5
e Eh e2
1
15
terminal 1 index area
20 Dh 0
16
X
2.5 scale
5 mm
DIMENSIONS (mm are the original dimensions) UNIT mm A(1) max. 1 A1 0.05 0.00 b 0.38 0.23 c 0.2 D(1) 5.1 4.9 Dh 3.25 2.95 E(1) 5.1 4.9 Eh 3.25 2.95 e 0.65 e1 2.6 e2 2.6 L 0.75 0.50 v 0.1 w 0.05 y 0.05 y1 0.1
Note 1. Plastic or metal protrusions of 0.075 mm maximum per side are not included. OUTLINE VERSION SOT662-1 REFERENCES IEC --JEDEC MO-220 JEITA --EUROPEAN PROJECTION ISSUE DATE 01-08-08 02-10-22
Fig 24. Package outline SOT662-1 (HVQFN20)
PCA9545A_45B_45C_7 (c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
22 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
14. Soldering of SMD packages
This text provides a very brief insight into a complex technology. A more in-depth account of soldering ICs can be found in Application Note AN10365 "Surface mount reflow soldering description".
14.1 Introduction to soldering
Soldering is one of the most common methods through which packages are attached to Printed Circuit Boards (PCBs), to form electrical circuits. The soldered joint provides both the mechanical and the electrical connection. There is no single soldering method that is ideal for all IC packages. Wave soldering is often preferred when through-hole and Surface Mount Devices (SMDs) are mixed on one printed wiring board; however, it is not suitable for fine pitch SMDs. Reflow soldering is ideal for the small pitches and high densities that come with increased miniaturization.
14.2 Wave and reflow soldering
Wave soldering is a joining technology in which the joints are made by solder coming from a standing wave of liquid solder. The wave soldering process is suitable for the following:
* Through-hole components * Leaded or leadless SMDs, which are glued to the surface of the printed circuit board
Not all SMDs can be wave soldered. Packages with solder balls, and some leadless packages which have solder lands underneath the body, cannot be wave soldered. Also, leaded SMDs with leads having a pitch smaller than ~0.6 mm cannot be wave soldered, due to an increased probability of bridging. The reflow soldering process involves applying solder paste to a board, followed by component placement and exposure to a temperature profile. Leaded packages, packages with solder balls, and leadless packages are all reflow solderable. Key characteristics in both wave and reflow soldering are:
* * * * * *
Board specifications, including the board finish, solder masks and vias Package footprints, including solder thieves and orientation The moisture sensitivity level of the packages Package placement Inspection and repair Lead-free soldering versus SnPb soldering
14.3 Wave soldering
Key characteristics in wave soldering are:
* Process issues, such as application of adhesive and flux, clinching of leads, board
transport, the solder wave parameters, and the time during which components are exposed to the wave
* Solder bath specifications, including temperature and impurities
PCA9545A_45B_45C_7 (c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
23 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
14.4 Reflow soldering
Key characteristics in reflow soldering are:
* Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads to
higher minimum peak temperatures (see Figure 25) than a SnPb process, thus reducing the process window
* Solder paste printing issues including smearing, release, and adjusting the process
window for a mix of large and small components on one board
* Reflow temperature profile; this profile includes preheat, reflow (in which the board is
heated to the peak temperature) and cooling down. It is imperative that the peak temperature is high enough for the solder to make reliable solder joints (a solder paste characteristic). In addition, the peak temperature must be low enough that the packages and/or boards are not damaged. The peak temperature of the package depends on package thickness and volume and is classified in accordance with Table 10 and 11
Table 10. SnPb eutectic process (from J-STD-020C) Package reflow temperature (C) Volume (mm3) < 350 < 2.5 2.5 Table 11. 235 220 Lead-free process (from J-STD-020C) Package reflow temperature (C) Volume (mm3) < 350 < 1.6 1.6 to 2.5 > 2.5 260 260 250 350 to 2000 260 250 245 > 2000 260 245 245 350 220 220
Package thickness (mm)
Package thickness (mm)
Moisture sensitivity precautions, as indicated on the packing, must be respected at all times. Studies have shown that small packages reach higher temperatures during reflow soldering, see Figure 25.
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
24 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
temperature
maximum peak temperature = MSL limit, damage level
minimum peak temperature = minimum soldering temperature
peak temperature
time
001aac844
MSL: Moisture Sensitivity Level
Fig 25. Temperature profiles for large and small components
For further information on temperature profiles, refer to Application Note AN10365 "Surface mount reflow soldering description".
15. Abbreviations
Table 12. Acronym CDM DUT ESD HBM IC I2C-bus LSB MM MSB PCB POR SMBus Abbreviations Description Charged-Device Model Device Under Test ElectroStatic Discharge Human Body Model Integrated Circuit Inter-Integrated Circuit bus Least Significant Bit Machine Model Most Significant Bit Printed-Circuit Board Power-On Reset System Management Bus
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
25 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
16. Revision history
Table 13. Revision history Release date 20090619 Data sheet status Product data sheet Change notice Supersedes PCA9545A_45B_45C_6 Document ID PCA9545A_45B_45C_7 Modifications:
*
Table 9 "Dynamic characteristics": - Symbol tf: changed Unit from "s" to "ns" - Symbol Cb: changed Unit from "s" to "pF"
*
PCA9545A_45B_45C_6 PCA9545A_45B_45C_5 PCA9545A_4 PCA9545A_3 (9397 750 14311) PCA9545A_2 (9397 750 13989) PCA9545A_1 (9397 750 13309)
Updated soldering information. Product data sheet Product data sheet Product data sheet Product data sheet Objective data sheet Objective data sheet PCA9545A_45B_45C_5 PCA9545A_4 PCA9545A_3 PCA9545A_2 PCA9545A_1 -
20070319 20061017 20060925 20050303 20040929 20040728
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
26 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
17. Legal information
17.1 Data sheet status
Document status[1][2] Objective [short] data sheet Preliminary [short] data sheet Product [short] data sheet
[1] [2] [3]
Product status[3] Development Qualification Production
Definition This document contains data from the objective specification for product development. This document contains data from the preliminary specification. This document contains the product specification.
Please consult the most recently issued document before initiating or completing a design. The term `short data sheet' is explained in section "Definitions". The product status of device(s) described in this document may have changed since this document was published and may differ in case of multiple devices. The latest product status information is available on the Internet at URL http://www.nxp.com.
17.2 Definitions
Draft -- The document is a draft version only. The content is still under internal review and subject to formal approval, which may result in modifications or additions. NXP Semiconductors does not give any representations or warranties as to the accuracy or completeness of information included herein and shall have no liability for the consequences of use of such information. Short data sheet -- A short data sheet is an extract from a full data sheet with the same product type number(s) and title. A short data sheet is intended for quick reference only and should not be relied upon to contain detailed and full information. For detailed and full information see the relevant full data sheet, which is available on request via the local NXP Semiconductors sales office. In case of any inconsistency or conflict with the short data sheet, the full data sheet shall prevail.
damage. NXP Semiconductors accepts no liability for inclusion and/or use of NXP Semiconductors products in such equipment or applications and therefore such inclusion and/or use is at the customer's own risk. Applications -- Applications that are described herein for any of these products are for illustrative purposes only. NXP Semiconductors makes no representation or warranty that such applications will be suitable for the specified use without further testing or modification. Limiting values -- Stress above one or more limiting values (as defined in the Absolute Maximum Ratings System of IEC 60134) may cause permanent damage to the device. Limiting values are stress ratings only and operation of the device at these or any other conditions above those given in the Characteristics sections of this document is not implied. Exposure to limiting values for extended periods may affect device reliability. Terms and conditions of sale -- NXP Semiconductors products are sold subject to the general terms and conditions of commercial sale, as published at http://www.nxp.com/profile/terms, including those pertaining to warranty, intellectual property rights infringement and limitation of liability, unless explicitly otherwise agreed to in writing by NXP Semiconductors. In case of any inconsistency or conflict between information in this document and such terms and conditions, the latter will prevail. No offer to sell or license -- Nothing in this document may be interpreted or construed as an offer to sell products that is open for acceptance or the grant, conveyance or implication of any license under any copyrights, patents or other industrial or intellectual property rights. Export control -- This document as well as the item(s) described herein may be subject to export control regulations. Export might require a prior authorization from national authorities.
17.3 Disclaimers
General -- Information in this document is believed to be accurate and reliable. However, NXP Semiconductors does not give any representations or warranties, expressed or implied, as to the accuracy or completeness of such information and shall have no liability for the consequences of use of such information. Right to make changes -- NXP Semiconductors reserves the right to make changes to information published in this document, including without limitation specifications and product descriptions, at any time and without notice. This document supersedes and replaces all information supplied prior to the publication hereof. Suitability for use -- NXP Semiconductors products are not designed, authorized or warranted to be suitable for use in medical, military, aircraft, space or life support equipment, nor in applications where failure or malfunction of an NXP Semiconductors product can reasonably be expected to result in personal injury, death or severe property or environmental
17.4 Trademarks
Notice: All referenced brands, product names, service names and trademarks are the property of their respective owners. I2C-bus -- logo is a trademark of NXP B.V.
18. Contact information
For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com
PCA9545A_45B_45C_7
(c) NXP B.V. 2009. All rights reserved.
Product data sheet
Rev. 07 -- 19 June 2009
27 of 28
NXP Semiconductors
PCA9545A/45B/45C
4-channel I2C-bus switch with interrupt logic and reset
19. Contents
1 2 3 3.1 4 5 5.1 5.2 6 6.1 6.2 6.2.1 6.2.2 6.3 6.4 6.5 7 7.1 7.2 7.3 7.4 7.5 8 9 10 11 12 13 14 14.1 14.2 14.3 14.4 15 16 17 17.1 17.2 17.3 17.4 18 19 General description . . . . . . . . . . . . . . . . . . . . . . 1 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Ordering information . . . . . . . . . . . . . . . . . . . . . 2 Ordering options . . . . . . . . . . . . . . . . . . . . . . . . 2 Block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Pinning information . . . . . . . . . . . . . . . . . . . . . . 4 Pinning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Pin description . . . . . . . . . . . . . . . . . . . . . . . . . 5 Functional description . . . . . . . . . . . . . . . . . . . 6 Device address . . . . . . . . . . . . . . . . . . . . . . . . . 6 Control register . . . . . . . . . . . . . . . . . . . . . . . . . 7 Control register definition . . . . . . . . . . . . . . . . . 7 Interrupt handling . . . . . . . . . . . . . . . . . . . . . . . 8 RESET input . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Power-on reset . . . . . . . . . . . . . . . . . . . . . . . . . 9 Voltage translation . . . . . . . . . . . . . . . . . . . . . . 9 Characteristics of the I2C-bus. . . . . . . . . . . . . 10 Bit transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 START and STOP conditions . . . . . . . . . . . . . 10 System configuration . . . . . . . . . . . . . . . . . . . 11 Acknowledge . . . . . . . . . . . . . . . . . . . . . . . . . 11 Bus transactions . . . . . . . . . . . . . . . . . . . . . . . 12 Application design-in information . . . . . . . . . 13 Limiting values. . . . . . . . . . . . . . . . . . . . . . . . . 14 Static characteristics. . . . . . . . . . . . . . . . . . . . 15 Dynamic characteristics . . . . . . . . . . . . . . . . . 17 Test information . . . . . . . . . . . . . . . . . . . . . . . . 19 Package outline . . . . . . . . . . . . . . . . . . . . . . . . 20 Soldering of SMD packages . . . . . . . . . . . . . . 23 Introduction to soldering . . . . . . . . . . . . . . . . . 23 Wave and reflow soldering . . . . . . . . . . . . . . . 23 Wave soldering . . . . . . . . . . . . . . . . . . . . . . . . 23 Reflow soldering . . . . . . . . . . . . . . . . . . . . . . . 24 Abbreviations . . . . . . . . . . . . . . . . . . . . . . . . . . 25 Revision history . . . . . . . . . . . . . . . . . . . . . . . . 26 Legal information. . . . . . . . . . . . . . . . . . . . . . . 27 Data sheet status . . . . . . . . . . . . . . . . . . . . . . 27 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Disclaimers . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Trademarks . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 Contact information. . . . . . . . . . . . . . . . . . . . . 27 Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Please be aware that important notices concerning this document and the product(s) described herein, have been included in section `Legal information'.
(c) NXP B.V. 2009.
All rights reserved.
For more information, please visit: http://www.nxp.com For sales office addresses, please send an email to: salesaddresses@nxp.com Date of release: 19 June 2009 Document identifier: PCA9545A_45B_45C_7

▲Up To Search▲

Price & Availability of PCA9545A

	To Download PCA9545A Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .