PCA9601
Dual bidirectional bus buffer
Rev. 3.1 — 4 January 2022
1
Product data sheet
General description
2
The PCA9601 is designed to isolate I C-bus capacitance, allowing long buses to be
driven in point-to-point or multipoint applications of up to 4 000 pF. The PCA9601 is
a higher-speed version of the P82B96 and a higher drive version of the PCA9600
that allows many more Fast-mode Plus (Fm+) slaves on remote daughter cards in
applications with temperature range of 0 °C to 85 °C.
2
It creates a non-latching, bidirectional, logic interface between a normal I C-bus and a
range of other higher capacitance or different voltage bus configurations. It can operate
at speeds up to at least 1 MHz, and the high drive side is compatible with the Fast-mode
Plus specifications.
The PCA9601 features temperature-stabilized logic voltage levels at its SX/SY interface
2
making it suitable for interfacing with buses that have non I C-bus-compliant logic levels
such as SMBus, PMBus, or with microprocessors that use those same TTL logic levels.
15 mA drive capability over 0 °C to 85 °C at SX/SY allows driving a 5 V Fm+ bus with
470 pF loading.
2
The separation of the bidirectional I C-bus signals into unidirectional TX and RX signals
enables the SDA and SCL signals to be transmitted via balanced transmission lines
(twisted pairs), or with galvanic isolation using opto or magnetic coupling. The TX and RX
signals may be connected together to provide a normal bidirectional signal.
2
Features and benefits
•
•
•
•
•
•
•
•
•
•
2
Bidirectional data transfer of I C-bus signals
15 mA SX/SY sink capability yields 5 V Fm+ bus rise time with 470 pF loads
Isolates capacitance allowing > 400 pF on SX/SY side and 4000 pF on TX/TY side
1 MHz operation on up to 20 meters of wire (see AN10658)
2
Supply voltage range of 2.5 V to 15 V with I C-bus logic levels on SX/SY side
independent of supply voltage
2
Splits I C-bus signal into pairs of forward/reverse TX/RX, TY/RY signals for interface
with opto-electrical isolators and similar devices that need unidirectional input and
output signal paths
Low power supply current
ESD protection exceeds 3500 V HBM per JESD22-A114, and 1400 V CDM per
JESD22-C101
Latch-up testing is done to JEDEC Standard JESD78 which exceeds 100 mA
Packages offered: SO8 and TSSOP8 (MSOP8)
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
3
Applications
2
• Interface between I C-buses operating at different logic levels (for example, 5 V and 3
V or 15 V)
2
• Interface between I C-bus and SMBus (350 μA) standard or Fm+ standard
2
• Simple conversion of I C-bus SDA or SCL signals to multi-drop differential bus
hardware, for example, via compatible PCA82C250
2
• Interfaces with opto-couplers to provide opto-isolation between I C-bus nodes up to 1
MHz
• Long distance point-to-point or multipoint architectures
4
Ordering information
Table 1. Ordering information
Type number
Topside
marking
Package
Name
Description
Version
PCA9601D
PCA9601
SO8
plastic small outline package; 8 leads; body width 3.9 mm
SOT96-1
PCA9601DP
9601
TSSOP8
plastic thin shrink small outline package; 8 leads; body width 3 mm
SOT505-1
4.1 Ordering options
Table 2. Ordering options
Type number
Orderable part
number
Package
Packing method
PCA9601D
PCA9601D,118
SO8
PCA9601DP
PCA9601DP,118
PCA9601DPZ
[1]
[2]
[3]
[2]
[1]
Minimum order
quantity
Temperature
REEL 13" Q1/T1
*STANDARD MARK SMD
2500
Tamb = -40 °C to +85 °C
TSSOP8
REEL 13" Q1/T1
*STANDARD MARK SMD
2500
Tamb = -40 °C to +85 °C
TSSOP8
REEL 13" Q1/T1 SSB
2500
Tamb = -40 °C to +85 °C
[3]
Standard packing quantities and other packaging data are available at www.nxp.com/packages/.
Orderable part number PCA9601DPZ is drop in alternate for PCA9601DP,118
This packing method uses a Static Shielding Bag (SSB) solution. Material should be kept in the sealed bag between uses.
5
Block diagram
VCC (2.5 V to 15 V)
8
SX (SDA)
static level offset
card side
1
PCA9601
3
2
SY (SCL)
5
7
6
TX (TxD, SDA)
RX (RxD, SDA)
TY (TxD, SCL)
higher drive,
longer distance side
RY (RxD, SCL)
4
GND
002aae873
Figure 1. Block diagram of PCA9601
PCA9601
Product data sheet
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2 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
6
Pinning information
6.1 Pinning
SX
1
8
VCC
RX
2
7
SY
TX
3
6
GND
PCA9601D
4
5
SX
1
8
VCC
RX
2
7
SY
RY
TX
3
6
RY
TY
GND
4
5
TY
002aae874
PCA9601DP
002aae875
Figure 2. Pin configuration for SO8
Figure 3. Pin configuration for TSSOP8 (MSOP8)
6.2 Pin description
Table 3. Pin description
7
Symbol
Pin
Description
SX
1
I C-bus (SDA or SCL)
RX
2
receive signal
TX
3
transmit signal
GND
4
negative supply voltage
TY
5
transmit signal
RY
6
receive signal
SY
7
I C-bus (SDA or SCL)
VCC
8
positive supply voltage
2
2
Functional description
Refer to Figure 1.
2
The PCA9601 has two identical buffers allowing buffering of SDA and SCL I C-bus
2
signals. Each buffer is made up of two logic signal paths, a forward path from the I C-bus
interface, pins SX and SY which drive the buffered bus, and a reverse signal path from
2
the buffered bus input, pins RX and RY to drive the I C-bus interface. These paths:
2
• sense the voltage state of I C-bus pins SX (and SY) and transmit this state to pin TX
(and TY respectively), and
2
• sense the state of pins RX and RY and pull the I C-bus pin LOW whenever pin RX or
pin RY is LOW.
The rest of this discussion will address only the ‘X’ side of the buffer; the ‘Y’ side is
identical.
7.1 Static level offset card side
2
The I C-bus pin SX is specified to allow interfacing with Fast-mode, Fm+ and TTL-based
systems.
PCA9601
Product data sheet
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Rev. 3.1 — 4 January 2022
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3 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
2
The logic threshold voltage levels at SX on this I C-bus are independent of the IC supply
2
voltage VCC. The maximum I C-bus supply voltage is 15 V.
7.1.1 Fast-mode operation
When interfacing with Fast-mode systems, the SX pin is guaranteed to sink the normal
3 mA with a VOL of 0.74 V maximum. That guarantees compliance with the Fast-mode
2
2
I C-bus specification for all I C-bus voltages greater than 3 V, as well as compliance with
SMBus or other systems that use TTL switching levels.
SX is guaranteed to sink an external 3 mA in addition to its internally sourced pull-up of
typically 300 μA (maximum 1 mA at -40 °C). When selecting the pull-up for the bus at
SX, the sink capability of other connected drivers should be taken into account. Most TTL
devices are specified to sink at least 4 mA so then the pull-up is limited to 3 mA by the
requirement to ensure the 0.8 V TTL LOW.
2
2
For Fast-mode I C-bus operation, the other connected I C-bus parts may have the
minimum sink capability of 3 mA. SX sources typically 300 μA (maximum 1 mA at -40
°C), which forms part of the external driver loading. When selecting the pull-up it is
necessary to subtract the SX pin pull-up current, so, worst-case at -40 °C, the allowed
pull-up can be limited (by external drivers) to 2 mA.
7.1.2 Fast-mode Plus operation
When the interface at SX is an Fm+ bus with a voltage greater than 4 V, its higher
specified sink capability may be used. PCA9601 has a guaranteed sink capability of
15 mA at VOL = 1 V maximum over 0 °C to 85 °C. That 1 V complies with the bus LOW
requirement (0.25Vbus) of any Fm+ bus operating at 4 V or greater. Since the other
connected Fm+ devices have a drive capability greater than 20 mA, the pull-up may be
selected for 15 mA sink current at VOL = 1 V. For a nominal 5 V bus (5.5 V maximum) the
allowed pull-up is (5.5 V - 1 V) / 15 mA = 300 Ω. With 300 Ω pull-up, the Fm+ rise time of
120 ns maximum can be met with total bus loading up to 470 pF.
7.2 High drive, long distance side
The logic level on RX is determined from the power supply voltage VCC of the chip.
Logic LOW is below 40 % of VCC, and logic HIGH is above 55 % of VCC (with a typical
switching threshold just slightly below half VCC).
TX is an open-collector output without ESD protection diodes to VCC. It may be
connected via a pull-up resistor to a supply voltage in excess of VCC, as long as the 15
2
V rating is not exceeded. It has a larger current sinking capability than a normal I C-bus
device, being able to sink a static current of greater than 30 mA, and typical 100 mA
dynamic pull-down capability as well.
2
A logic LOW is transmitted to TX when the voltage at I C-bus pin SX is below 0.425
2
V. A logic LOW at RX will cause I C-bus pin SX to be pulled to a logic LOW level in
2
accordance with I C-bus requirements (maximum 1.5 V in 5 V applications) but not low
enough to be looped back to the TX output and cause the buffer to latch LOW.
2
The LOW level this chip can achieve on the I C-bus by a LOW at RX is typically 0.64 V
when sinking 1 mA.
2
If the supply voltage VCC fails, then neither the I C-bus nor the TX output will be held
LOW. Their open-collector configuration allows them to be pulled up to the rated
PCA9601
Product data sheet
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Rev. 3.1 — 4 January 2022
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
maximum of 15 V even without VCC present. The input configuration on SX and RX also
presents no loading of external signals when VCC is not present.
The effective input capacitance of any signal pin, measured by its effect on bus rise
times, is less than 10 pF for all bus voltages and supply voltages including VCC = 0 V.
7.3 Connections to other bus buffers
Two or more SX or SY I/Os must not be interconnected. The PCA9601 design does
2
not support this configuration. Bidirectional I C-bus signals do not allow any direction
control pin so, instead, slightly different logic LOW voltage levels are used at SX/SY
2
to avoid latching of this buffer. A ‘regular I C-bus LOW’ applied at the RX/RY of a
PCA9601 will be propagated to SX/SY as a ‘buffered LOW’ with a slightly higher voltage
level. If this special ‘buffered LOW’ is applied to the SX/SY of another PCA9601, that
2
second PCA9601 will not recognize it as a ‘regular I C-bus LOW’ and will not propagate
it to its TX/TY output. The SX/SY side of PCA9601 may not be connected to similar
buffers that rely on special logic thresholds for their operation, for example P82B96,
PCA9511A, PCA9515A, ‘B’ side of PCA9517, etc. The SX/SY side is only intended for,
2
2
and compatible with, the normal I C-bus logic voltage levels of I C-bus master and slave
chips, or even TX/RX signals of a second PCA9601 or P82B96 if required. The TX/RX
2
2
and TY/RY I/O pins use the standard I C-bus logic voltage levels of all I C-bus parts.
There are no restrictions on the interconnection of the TX/RX and TY/RY I/O pins to
other PCA9601s, for example in a star or multipoint configuration with the TX/RX and
TY/RY I/O pins on the common bus and the SX/SY side connected to the line card slave
2
devices. For more details see Application Note AN10658, "Sending I C-bus signals via
long communication cables".
7.4 Comparison of PCA9601/PCA9600 and P82B96
The PCA9601 is a direct upgrade of the P82B96 with the significant differences
summarized in Table 4. The PCA9601 provides improved interface to the higher drive
Fast-mode Plus devices on the SX/SY sides.
Table 4. PCA9601/PCA9600 versus P82B96
Detail
PCA9601/PCA9600
P82B96
Supply voltage (VCC) range:
2.5 V to 15 V
2 V to 15 V
Maximum operating bus voltage
(independent of VCC):
15 V
15 V
5 mA
1 mA
0.5 V over -40 °C to +85 °C
0.65 V at 25 °C
Typical operating supply current:
2
Typical LOW-level input voltage on I C-bus
(SX/SY side):
2
LOW-level output voltage on I C-bus (SX/SY 0.74 V (max.) over -40 °C to +85 °C
side; 3 mA sink):
2
0.88 V (typ.) at 25 °C
LOW-level output voltage on Fm+ I C-bus
(SX/SY side; 15 mA sink):
1 V (max.) over 0 °C to 85 °C
(PCA9601 only)
n/a
Temperature coefficient of VIL / VOL:
0 mV/°C
-2 mV/°C
2
2
Logic voltage levels on SX/SY bus
(independent of VCC):
compatible with I C-bus and similar
compatible with I C-bus and similar
buses using TTL levels (SMBus, etc.) buses using TTL levels (SMBus, etc.)
Typical propagation delays:
< 100 ns
PCA9601
Product data sheet
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< 200 ns
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Table 4. PCA9601/PCA9600 versus P82B96...continued
Detail
PCA9601/PCA9600
2
TX/RX switching specifications (I C-bus
compliant):
P82B96
yes, all classes including 1 MHz Fm+ yes, all classes including Fm+
2
RX logic levels with tighter control than I Cbus limit of 30 % to 70 %:
yes, 40 % to 55 % (48 % nominal)
yes, 42 % to 58 % (50 % nominal)
Maximum bus speed:
> 1 MHz
> 400 kHz
ESD rating HBM per JESD22-A114:
> 3500 V
> 3500 V
Package:
SO8, TSSOP8 (MSOP8)
SO8, TSSOP8 (MSOP8)
2
When the device driving the PCA9601/PCA9600 is an I C-bus compatible device, then
the PCA9601 is an improvement on the P82B96 as shown in Table 4. There will always
2
be exceptions however, and if the device driving the bus buffer is not I C-bus compatible
(e.g., you need to use the micro already in the system and bit-bang using two GPIO pins)
then here are some considerations that would point to using the P82B96 instead:
• When the pull-up must be the weakest one possible. The spec is 200 μA for P82B96,
but it typically works even below that. And if designing for a temperature range -40 °C
up to +60 °C, then the driver when sinking 200 μA only needs to drive a guaranteed low
of 0.55 V. For the PCA9601/PCA9600, over that same temperature range and when
sinking 1.3 mA (at -40 °C), the device driving the bus buffer must provide the required
low of 0.425 V.
• When the lower operating temperature range is restricted (say 0 °C). The P82B96
larger SX voltage levels then make a better typical match with the driver, even when
the supply is as low as 3.3 V.
2
For an I C-bus compliant driver on 3.3 V the P82B96 is required to guarantee a bus
low that is below 0.83 V. P82B96 guarantees that with a 200 μA pull-up.
2
• When the operating temperature range is restricted at both limits. An I C driver's typical
output is well below 0.4 V and the P82B96 typically requires 0.6 V input even at +60
°C, so there is a reasonable margin. The PCA9601/PCA9600 requires a typical input
low of 0.5 V so its typical margin is smaller. At 0 °C the driver requires a typical input
low of 1.16 V and P82B96 provides 0.75 V, so again the typical margin is already quite
big and even though PCA9601/PCA9600 is better, providing 0.7 V, that difference is not
big.
8
Limiting values
Table 5. Limiting values
In accordance with the Absolute Maximum Rating System (IEC 60134).
Voltages with respect to pin GND.
PCA9601
Product data sheet
Symbol
Parameter
Conditions
VCC
supply voltage
VCC to GND
2
2
Min
Max
Unit
-0.3
+18
V
-0.3
+18
V
VI2C-bus
I C-bus voltage
SX and SY; I C-bus
SDA or SCL
VO
output voltage
TX and TY; buffered
output
[1]
-0.3
+18
V
VI
input voltage
RX and RY; receive
input
[1]
-0.3
+18
V
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© NXP B.V. 2022. All rights reserved.
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Table 5. Limiting values...continued
In accordance with the Absolute Maximum Rating System (IEC 60134).
Voltages with respect to pin GND.
Symbol
2
II2C-bus
I C-bus current
Ptot
total power dissipation
Tj
junction temperature
Tstg
storage temperature
Tamb
ambient temperature
[1]
9
Parameter
Conditions
2
SX and SY; I C-bus
SDA or SCL
operating range
operating
Min
Max
Unit
-
250
mA
-
300
mW
-40
+125
°C
-55
+125
°C
-40
+85
°C
See also Section 10.2.
Characteristics
Table 6. Characteristics
Tamb = -40 °C to +85 °C unless otherwise specified; voltages are specified with respect to GND with VCC = 2.5 V to 15 V
unless otherwise specified. Typical values are measured at VCC = 5 V and Tamb = 25 °C.
Symbol Parameter
Conditions
Min
Typ
Max
Unit
Power supply
VCC
supply voltage
operating
2.5
-
15
V
ICC
supply current
VCC = 5 V; buses HIGH
-
5.2
6.75
mA
VCC = 15 V; buses HIGH
-
5.5
7.3
mA
per TX/TY output driven LOW; VCC
= 5.5 V
-
1.4
3.0
mA
-
-
15
V
-
-
15
V
0.3
-
15
mA
ΔICC
additional supply current
Bus pull-up (load) voltages and currents
2
Pins SX and SY; I C-bus
VI
input voltage
open-collector; RX and RY HIGH
VO
output voltage
open-collector; RX and RY HIGH
[1]
IO
output current
static; VSX = VSY = 0.4 V
IO(sink)
output sink current
VSX = VSY = 1 V; RX and RY LOW;
Tamb = 0 °C to 85 °C
15
-
-
mA
IL
leakage current
VSX = VSY = 15 V; RX and RY HIGH
-
-
10
μA
Pins TX and TY
VO
output voltage
open-collector
-
-
15
V
Iload
load current
maximum recommended on
buffered bus; VTX = VTY = 0.4 V; SX
2
and SY LOW on I C-bus = 0.4 V
-
-
30
mA
IO
output current
from buffered bus; VTX = VTY = 1 V;
2
SX and SY LOW on I C-bus = 0.4 V
60
130
-
mA
IL
leakage current
on buffered bus; VTX = VTY = VCC =
15 V; SX and SY HIGH
-
-
10
μA
Input currents
PCA9601
Product data sheet
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Table 6. Characteristics...continued
Tamb = -40 °C to +85 °C unless otherwise specified; voltages are specified with respect to GND with VCC = 2.5 V to 15 V
unless otherwise specified. Typical values are measured at VCC = 5 V and Tamb = 25 °C.
Symbol Parameter
II
IL
Conditions
Min
Typ
Max
Unit
2
from I C-bus on SX and SY
input current
leakage current
RX and RY HIGH or LOW; SX
and SY LOW ≤ 1 V
[1]
-
-0.3
-1
mA
RX and RY HIGH; SX and SY
HIGH > 1.4 V
[1]
-
-
10
μA
from buffered bus on RX and RY;
SX and SY HIGH or LOW; VRX =
VRY = 0.4 V
[2]
-
-1.5
-10
μA
-
-
10
μA
ISX = ISY = 3 mA; Figure 6
-
0.7
0.74
V
ISX = ISY = 0.3 mA; Figure 5
-
0.6
0.65
V
-
0.85
1
V
-
0
-
%/K
-
-
425
mV
580
-
-
mV
-
0
-
%/K
-
V
on buffered bus input on RX and
RY; VRX = VRY = 15 V
Output logic LOW level
Pins SX and SY
VOL
on Standard-mode or Fast-mode
2
I C-bus
LOW-level output voltage
2
on 5 V Fm+ I C-bus
ISX = ISY = 15 mA; Tamb = 0 °C
to 85 °C
ΔV/ΔT
voltage variation with
temperature
ISX = ISY = 0.3 mA to 3 mA
Input logic switching threshold voltages
Pins SX and SY
VIL
LOW-level input voltage
Vth(IH)
HIGH-level input threshold
voltage
ΔV/ΔT
voltage variation with
temperature
2
on normal I C-bus; Figure 7
[3]
2
on normal I C-bus; Figure 8
Pins RX and RY
VIH
HIGH-level input voltage
fraction of applied VCC
0.55VCC -
Vth(i)
input threshold voltage
fraction of applied VCC
-
0.48VCC -
V
VIL
LOW-level input voltage
fraction of applied VCC
-
-
0.4VCC
V
50
-
-
mV
-
-
1
V
Logic level threshold difference
ΔV
voltage difference
SX and SY; SX output LOW at 0.3
mA to SX input HIGH maximum
[4]
Bus release on VCC failure
VCC
supply voltage
PCA9601
Product data sheet
SX, SY, TX and TY; voltage at
which all buses are to be released
at 25 °C
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Table 6. Characteristics...continued
Tamb = -40 °C to +85 °C unless otherwise specified; voltages are specified with respect to GND with VCC = 2.5 V to 15 V
unless otherwise specified. Typical values are measured at VCC = 5 V and Tamb = 25 °C.
Symbol Parameter
Conditions
Min
Typ
Max
Unit
ΔV/ΔT
Figure 9
-
-4
-
%/K
voltage variation with
temperature
Buffer response time
[5]
VCC = 5 V; pin TX pull-up resistor = 160 Ω; pin SX pull-up resistor = 2.2 kΩ; no capacitive load
td
delay time
VSX to VTX, VSY to VTY; on falling
input between VSX = input switching
threshold, and VTX output falling to
50 % VCC
-
50
-
ns
VSX to VTX, VSY to VTY; on rising
input between VSX = input switching
threshold, and VTX output reaching
50 % VCC
-
60
-
ns
VRX to VSX, VRY to VSY; on falling
input between VRX = input switching
threshold, and VSX output falling to
50 % VCC
-
100
-
ns
VRX to VSX, VRY to VSY; on rising
input between VRX = input switching
threshold, and VSX output reaching
50 % VCC
-
95
-
ns
effective input capacitance of any
signal pin measured by incremental
bus rise times; guaranteed by
design, not production tested
-
-
10
pF
Input capacitance
Ci
[1]
[2]
[3]
[4]
[5]
input capacitance
This bus pull-up current specification is intended to assist design of the bus pull-up resistor. It is not a specification of the sink capability (see VOL under
sub-section "Output logic LOW level"). When used on an Fm+ bus the load current is limited to 15 mA by the drive capability of PCA9601. When used
2
in a standard I C-bus the load current is limited by the drive capability of other devices on the bus. The maximum static sink current for a Standard/Fast2
mode I C-bus is 3 mA and PCA9601 is guaranteed to sink more than 3 mA at SX/SY when its pins are holding the bus LOW. However, when an external
device pulls the SX/SY pins below 1.4 V, the PCA9601 will source a current between 0 mA and 1 mA maximum. When that other external device is driving
2
LOW it will pull the bus connected to SX or SY down to, or below, the 0.4 V level referenced in the I C-bus specification and in these test conditions. Then
that device must be able to sink up to 1 mA coming from SX/SY plus the usual pull-up current. Therefore in Standard and Fast-mode systems the external
pull-up used at SX/SY should be limited to 2 mA. The typical and maximum currents sourced by SX/SY as a function of junction temperature are shown in
Figure 10, and the equivalent circuit at the SX/SY interface is shown in Figure 4.
Valid over temperature for VCC ≤ 5 V. At higher VCC, this current may increase to maximum -20 μA at VCC = 15 V.
The input logic threshold is independent of the supply voltage.
The minimum value requirement for pull-up current, 0.3 mA, guarantees that the minimum value for VSX output LOW will always exceed the maximum VSX
input HIGH level to eliminate any possibility of latching. The specified difference is guaranteed by design within any IC. While the tolerances on absolute
levels allow a small probability, the LOW from one SX output is recognized by an SX input of another PCA9601, this has no consequences for normal
applications. In any design the SX pins of different ICs should never be linked because the resulting system would be very susceptible to induced noise
2
and would not support all I C-bus operating modes.
The fall time of VTX from 5 V to 2.5 V in the test is approximately 10 ns.
The fall time of VSX from 5 V to 2.5 V in the test is approximately 20 ns.
The rise time of VTX from 0 V to 2.5 V in the test is approximately 15 ns.
The rise time of VSX from 0.7 V to 2.5 V in the test is approximately 25 ns.
PCA9601
Product data sheet
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
VCC
≤ 1 mA
SX (SY)
Vref
002aac838
Figure 4. Equivalent circuit at SX/SY
002aac839
800
VOL
(mV)
VOL
(mV)
700
002aac840
800
700
(1)
(2)
(1)
(2)
600
600
500
400
- 50
500
- 25
0
25
50
75
100
125
Tj (°C)
400
- 50
- 25
0
25
50
75
100
125
Tj (°C)
VOL at SX typical and limits over temperature.
1. Maximum.
2. Typical.
VOL at SX typical and limits over temperature.
1. Maximum.
2. Typical.
Figure 5. VOL as a function of junction temperature (IOL
= 0.3 mA)
Figure 6. VOL as a function of junction temperature (IOL
= 3 mA)
002aag005
600
VIL
(mV)
500
VIH
(mV)
typical
002aag006
600
500
minimum
typical
maximum
400
400
300
300
200
- 50
- 25
0
25
50
75
100
125
Tj (°C)
200
- 50
- 25
0
25
50
75
100
125
Tj (°C)
VIL at SX changes over temperature range.
VIH at SX changes over temperature range.
Figure 7. VIL as a function of junction temperature;
maximum and typical values
Figure 8. VIH as a function of junction temperature;
minimum and typical values
PCA9601
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
002aac075
1400
VCC(max)
(mV)
1200
1000
(1)
(2)
600
800
400
600
400
- 50
001aai062
1000
II
(µA)
800
200
- 25
0
25
50
75
100
125
Tj (°C)
0
- 50
1. Maximum.
2. Typical.
0
25
50
75
100
125
Tj (°C)
Figure 10. Current sourced out of SX/SY as a function of
junction temperature if these pins are externally pulled
to 0.4 V or lower
Figure 9. VCC bus release limit over temperature;
maximum values
VOL
(V)
- 25
002aaf484
1.4
1.2
1.0
0.8
0.6
0.4
0.2
0
0
10
20
ISX, ISY (mA)
30
Figure 11. Typical SX/SY current versus LOW-level output voltage
10 Application information
Refer to application notes AN10658 and AN255 for more detailed application information.
VCC (2.5 V to 15 V)
5V
TX
(SDA)
I2C-bus
SDA
RX
(SDA)
PCA9601
R1
'SDA' (new levels)
002aae876
2
Figure 12. Interfacing a standard 3 mA I C-bus or one with TTL levels (e.g. SMBus) to
higher voltage or higher current sink (e.g. Fast-mode Plus) devices
PCA9601
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
VCC
R2
VCC1
R4
R5
RX
(SDA)
5V
R1
I2C-bus
SDA
I2C-bus
SDA
R3
TX
(SDA)
PCA9601
002aae877
This simple example may be limited, if using lowest-cost couplers, to speeds as low as 5 kHz.
Refer to application notes for schematics suitable for operation to 400 kHz or higher.
2
Figure 13. Galvanic isolation of I C-bus nodes via opto-couplers
main enclosure
3.3 V to 5 V
remote control enclosure
12 V
3.3 V to 5 V
12 V
long cables
SDA
SDA
3.3 V to 5 V
12 V
3.3 V to 5 V
SCL
SCL
PCA9601
PCA9601
002aae878
2
Figure 14. Long distance I C-bus communication
+V cable drive
VCC1
R2
SCL
VCC
RX
SX
SY
RX
R2
TX
TX
SX
TY
TY
R1
R1
RY
R1
R1
GND
SCL
I2C-BUS
SLAVE(S)
RY
cable
PCA9601
C2
R2
VCC
R2
I2C-BUS
MASTER
SDA
VCC2
SY
SDA
C2
C2
PCA9601
propagation
delay ≈ 5 ns/m
C2
BAT54A
BAT54A
GND
002aae879
Figure 15. Driving ribbon or flat telephone cables
PCA9601
Product data sheet
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Table 7. Examples of bus capability
Refer to Figure 15.
VCC1
(V)
+V
VCC2
cable (V)
(V)
R1
(Ω)
R2
C2
(kΩ) (pF)
Cable Cable
length capacitance
(m)
Cable
delay
Set master
nominal SCL
Effective
bus
clock
HIGH
LOW
speed
period period
(kHz)
(ns)
(ns)
Max. slave
response
delay
5
12
5
750
2.2
400
250
n/a (delay
based)
1.25 μs
600
3 850
125
normal
specification
400 kHz parts
5
12
5
750
2.2
220
100
n/a (delay
based)
500 ns
600
2 450
195
normal
specification
400 kHz parts
3.3
5
3.3
330
1
220
25
1 nF
125 ns
260
770
620
meets Fm+
specification
3.3
5
3.3
330
1
100
3
120 pF
15 ns
260
720
690
meets Fm+
specification
For more examples of faster alternatives for driving over longer cables such as Cat5
communication cable, see AN10658. Communication at 1 MHz is possible over short
cables and > 400 kHz is possible over 50 m of cable.
10.1 Calculating system delays and bus clock frequency
local master bus
buffered expansion bus
VCCM
remote slave bus
VCCB
SCL
MASTER
VCCS
Rm
Rb
SX
PCA9601
TX/RX
TX/RX
Rs
PCA9601
SCL
SLAVE
SX
I2C-BUS
I2C-BUS
Cm
master bus
capacitance
Cb
buffered bus
wiring capacitance
Cs
slave bus
capacitance
GND (0 V)
002aae880
9
Effective delay of SCL at slave: 120 + 17VCCM + (2.5 + 4 × 10 × Cb) × VCCB + 10VCCS (ns).
C = F; V = V.
Figure 16. Falling edge of SCL at master is delayed by the buffers and bus fall times
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PCA9601
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Dual bidirectional bus buffer
local master bus
buffered expansion bus
VCCM
VCCB
Rm
SCL
MASTER
Rb
SX
PCA9601
TX/RX
TX/RX
I2C-BUS
Cm
Cb
master bus
capacitance
buffered bus
wiring capacitance
GND (0 V)
002aae881
Effective delay of SCL at master: 115 + (Rm × Cm) + (0.7 × Rb × Cb) (ns).
C = F; R = Ω.
Figure 17. Rising edge of SCL at master is delayed (clock stretch) by buffer and bus rise times
local master bus
buffered expansion bus
VCCM
remote slave bus
VCCB
SDA
MASTER
VCCS
Rm
Rb
SX
PCA9601
TX/RX
TX/RX
Rs
PCA9601
SDA
SLAVE
SX
I2C-BUS
I2C-BUS
Cm
master bus
capacitance
Cb
buffered bus
wiring capacitance
Cs
slave bus
capacitance
GND (0 V)
002aae882
Effective delay of SDA at master: 115 + 0.2(Rs × Cs) + 0.7[(Rb × Cb) + (Rm × Cm)] (ns).
C = F; R = Ω.
Figure 18. Rising edge of SDA at slave is delayed by the buffers and bus rise times
Figure 16, Figure 17, and Figure 18 show the PCA9601 used to drive extended bus
2
wiring with relatively large capacitances linking two I C-bus nodes. It includes simplified
expressions for making the relevant timing calculations for 3.3 V or 5 V operation.
Because the buffers and the wiring introduce timing delays, it may be necessary to
decrease the nominal SCL frequency. In most cases the actual bus frequency will be
lower than the nominal Master timing due to bit-wise stretching of the clock periods.
The delay factors involved in calculation of the allowed bus speed are:
A: The propagation delay of the master signal through the buffers and wiring to the slave.
The important delay is that of the falling edge of SCL because this edge ‘requests’ the
data or acknowledge from a slave. See Figure 16.
PCA9601
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
B: The effective stretching of the nominal LOW period of SCL at the master caused by
the buffer and bus rise times. See Figure 17.
C: The propagation delay of the slave's response signal through the buffers and wiring
back to the master. The important delay is that of a rising edge in the SDA signal. Rising
edges are always slower and are therefore delayed by a longer time than falling edges.
(The rising edges are limited by the passive pull-up while falling edges are actively
driven); see Figure 18.
2
The timing requirement in any I C-bus system is that a slave's data response (which is
provided in response to a falling edge of SCL) must be received at the master before the
end of the corresponding LOW period of SCL as appears on the bus wiring at the master.
Since all slaves will, as a minimum, satisfy the worst case timing requirements of their
speed class (Fast-mode, Fm+, etc.), they must provide their response, allowing for the
set-up time, within the minimum allowed clock LOW period, e.g., 450 ns (max.) for Fm
+ parts. In systems that introduce additional delays it may be necessary to extend the
minimum clock LOW period to accommodate the ‘effective’ delay of the slave's response.
The effective delay of the slave’s response equals the total delays in SCL falling edge
from the master reaching the slave (Figure 16) minus the effective delay (stretch) of the
SCL rising edge (Figure 17) plus total delays in the slave's response data, carried on
SDA, reaching the master (Figure 18).
The master microcontroller should be programmed to produce a nominal SCL LOW
period as follows:
(1)
The actual LOW period will become (the programmed value + the stretching time B).
When this actual LOW period is then less than the specified minimum, the specified
minimum should be used.
Example 1:
It is required to connect an Fm+ slave, with Rs × Cs product of 100 ns, to a 5 V Fastmode system also having 100 ns Rm × Cm using two PCA9601’s to buffer a 5 V bus
with 4 nF loading and 160 Ω pull-up.
Calculate the allowed bus speed:
Delay A = 120 + 85 + (2.5 + [4 × 4]) × 5 + 50 = 347.5 ns
Delay B = 115 + 100 + 70 = 285 ns
Delay C = 115 + 20 + 0.7(100 + 100) = 275 ns
The maximum Fm+ slave response delay must be < 450 ns so the programmed LOW
period is calculated as:
LOW ≥ 450 + 347.5 - 285 + 275 + 100 = 887.5 ns
The actual LOW period will be 887.5 + 285 = 1 173 ns, which is below the Fast-mode
minimum, so the programmed LOW period must be increased to (1300 - 285) = 1015
ns, so the actual LOW equals the 1300 ns requirement and this shows that this Fastmode system may be safely run to its limit of 400 kHz.
Example 2:
It is required to buffer a Master with Fm+ speed capability, but only 3 mA sink
capability, to an Fm+ bus. All the system operates at 3.3 V. The Master Rm × Cm
product is 50 ns. Only one PCA9601 is used. The Fm+ bus becomes the buffered
bus. The Fm+ bus has 200 pF loading and 150 Ω pull-up, so its Rb × Cb product is 30
ns. The Fm+ slave has a specified data valid time tVD;DAT maximum of 300 ns.
PCA9601
Product data sheet
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Calculate the allowed maximum system bus speed. (Note that the fixed values in
the delay equations represent the internal propagation delays of the PCA9601. Only
one PCA9601 is used here, so those fixed values used below are taken from the
characteristics.)
The delays are:
Delay A = 40 + 56 + (2.5 + [4 × 0.2]) × 3.3 = 107 ns
Delay B = 115 + 50 + 21 = 186 ns
Delay C = 70 + 0.7(50 + 30) = 126 ns
The programmed LOW period is calculated as:
SCL LOW ≥ 300 + 117 - 186 + 126 + 50 = 407 ns
The actual LOW period will be 407 + 126 = 533 ns, which exceeds the minimum Fm
+ 500 ns requirement. This system requires the bus LOW period, and therefore cycle
time, to be increased by 33 ns so the system must run slightly below the 1 MHz limit.
The possible maximum speed has a cycle period of 1 033 ns or 968 kHz.
12 V
12 V
twisted-pair telephone wires,
USB, or flat ribbon cables;
up to 15 V logic levels,
include VCC and GND
3.3 V to 5 V
SX
SDA
TX
RX
3.3 V to 5 V
12 V
SY
SCL
TY
3.3 V 3.3 V
RY
PCA9601
PCA9601
PCA9601
PCA9601
SX
SX
SX
SY
SCL/SDA
SY
SCL/SDA
PCA9601
SY
SY SDA
SX SCL
SCL/SDA
no limit to the number of connected bus devices
002aae883
2
Figure 19. I C-bus multipoint application
2
There is an Excel calculator which makes it easy to determine the maximum I C-bus
clock speed when using the PCA9601. The calculator and instructions can be found at
www.nxp.com/clockspeedcalculator.
002aac932
7
VCC
6
(V)
VCC
6
(V)
(1)
5
(1)
5
4
4
3
3
(2)
2
(2)
2
1
1
(1)
0
-1
002aac933
7
(2)
0
100 200 300 400 500 600 700 800 900
time (ns)
1. TX output.
2. SX input.
Product data sheet
-1
(1)
(2)
0
100 200 300 400 500 600 700 800 900
time (ns)
1. TX/RX output.
2. SX input.
Figure 20. Propagation SX to TX with VRX = VCC = 3.3 V
(SX pull-up to 3.3 V; TX pull-up to 5.7 V)
PCA9601
(2)
0
Figure 21. Propagation SX to TX with RX tied to TX; VCC
= 3.3 V (SX pull-up to 3.3 V; TX pull-up to 5.7 V)
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
002aac934
7
VCC
6
(V)
5
4
(1)
3
(2)
2
(2)
1
0
-1
(1)
0
100 200 300 400 500 600 700 800 900
time (ns)
1. RX input.
2. SX output.
Figure 22. Propagation RX to SX (SX pull-up to 3.3 V; VCC = 3.3 V; RX pull-up to 4.6 V)
10.2 Negative undershoot below absolute minimum value
The reason why the IC pin reverse voltage on pins TX and RX in Table 5 is specified at
such a low value, -0.3 V, is not that applying larger voltages is likely to cause damage
but that it is expected that, in normal applications, there is no reason why larger DC
voltages will be applied. This ‘absolute maximum’ specification is intended to be a DC
2
or continuous ratings and the nominal DC I C-bus voltage LOW usually does not even
reach 0 V. Inside PCA9601 at every pin there is a large protective diode connected to
the GND pin and that diode will start to conduct when the pin voltage is more than about
-0.55 V with respect to GND at 25 °C ambient.
Figure 23 shows the measured characteristic for one of those diodes inside PCA9601.
The plot was made using a curve tracer that applies 50 Hz mains voltage via a series
resistor, so the pulse durations are long duration (several milliseconds) and are reaching
peaks of over 2 A when more than -1.5 V is applied. The IC becomes very hot during this
testing but it was not damaged. Whenever there is current flowing in any of these diodes
it is possible that there can be faulty operation of any IC. For that reason we put a
specification on the negative voltage that is allowed to be applied. It is selected so that, at
the highest allowed junction temperature, there will be a big safety factor that guarantees
the diode will not conduct and then we do not need to make any 100 % production tests
to guarantee the published specification.
For the PCA9601, in specific applications, there will always be transient overshoot and
ringing on the wiring that can cause these diodes to conduct. Therefore we designed the
IC to withstand those transients and as a part of the qualification procedure we made
tests, using DC currents to more than twice the normal bus sink currents, to be sure
that the IC was not affected by those currents. For example, the TX/TY and RX/RY pins
were tested to at least -80 mA which, from Figure 23, would be more than -0.8 V. The
correct functioning of the PCA9601 is not affected even by those large currents. The
Absolute Maximum (DC) ratings are not intended to apply to transients but to steady
state conditions. This explains why you will never see any problems in practice even if,
during transients, more than -0.3 V is applied to the bus interface pins of PCA9601.
Figure 23 also explains how the general Absolute Maximum DC specification was
selected. The current at 25 °C is near zero at -0.55 V. The PCA9601 is allowed to
operate with +125 °C junction and that would cause this diode voltage to decrease by
PCA9601
Product data sheet
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17 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
100 × 2 mV = 200 mV. So for zero current we need to specify -0.35 V and we publish -0.3
V just to have some extra margin.
Remark: You should not be concerned about the transients generated on the wiring
by a PCA9601 in normal applications and that is input to the TX/RX or TY/RY pins of
another PCA9601. Because not all ICs that may be driven by PCA9601 are designed to
tolerate negative transients, in Section 10.2.1 we show they can be managed if required.
002aaf063
0
diode current
(mA)
- 10- 1
-1
- 10
- 102
- 103
- 104
- 2.0
- 1.5
- 1.0
- 0.5
0
voltage (V)
Figure 23. Diode characteristic curve
10.2.1 Example with questions and answers
Question: On a falling edge of TX we measure undershoot at -800 mV at the linked
TX, RX pins of the PCA9601 that is generating the LOW, but the PCA9601 data sheet
specifies minimum -0.3 V. Does this mean that we violate the data sheet absolute
value?
Answer: For PCA9601 the -0.3 V Absolute Maximum rating is not intended to apply
to transients, it is a DC rating. As shown in Figure 24, there is no theoretical reason
for any undershoot at the IC that is driving the bus LOW and no significant undershoot
should be observed when using reasonable care with the ground connection of the
‘scope. It is more likely that undershoot observed at a driving PCA9601 is caused
by local stray inductance and capacitance in the circuit and by the oscilloscope
connections. As shown, undershoot will be generated by PCB traces, wiring, or
2
cables driven by a PCA9601 because the allowed value of the I C-bus pull-up resistor
generally is larger than that required to correctly terminate the wiring. In this example,
with no IC connected at the end of the wiring, the undershoot is about 2 V.
PCA9601
Product data sheet
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18 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
6
voltage
(V)
4
send
2
receive
0
-2
horizontal scale = 62.5 ns/div
5V
5V
5V
300 Ω
RX
SX
TX
send
PCA9601
time (ns)
2 meter
cable
300 Ω
receive
GND
002aaf078
Figure 24. Transients generated by the bus wiring
Question: We have 2 meters of cable in a bus that joins the TX/RX sides of two
PCA9601 devices. When one TX drives LOW the other PCA9601 TX/RX is driven to
-0.8 V for over 50 ns. What is the expected value and the theoretically allowed value
of undershoot?
Answer: Because the cable joining the two PCA9601s is a ‘transmission line’ that
will have a characteristic impedance around 100 Ω and it will be terminated by pullup resistors that are larger than that characteristic impedance there will always be
negative undershoot generated. The duration of the undershoot is a function of the
cable length and the input impedance of the connected IC. As shown in Figure 25, the
transient undershoot will be limited, by the diodes inside PCA9601, to around -0.8 V
and that will not cause problems for PCA9601. Those transients will not be passed
inside the IC to the SX/SY side of the IC.
PCA9601
Product data sheet
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19 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
6
voltage
(V)
4
2
receive
send
0
-2
horizontal scale = 62.5 ns/div
5V
5V
time (ns)
5V
300 Ω
RX
SX
TX
send
PCA9601
2 meter
cable
5V
300 Ω
receive
RX
SX
TX
GND
002aaf079
Figure 25. Wiring transients limited by the diodes in PCA9601
Question: If we input 800 mV undershoot at TX, RX pins, what kind of problem is
expected?
Answer: When that undershoot is generated by another PCA9601 and is simply the
result of the system wiring, then there will be no problems.
Question: Will we have any functional problem or reliability problem?
Answer: No.
Question: If we add 100 Ω to 200 Ω at signal line, the overshoot becomes slightly
smaller. Is this a good idea?
Answer: No, it is not necessary to add any resistance. When the logic signal
generated by TX or TY of PCA9601 drives long traces or wiring with ICs other than
PCA9601 being driven, then adding a Schottky diode (BAT54A) as shown in Figure 26
will clamp the wiring undershoot to a value that will not cause conduction of the IC’s
internal diodes.
PCA9601
Product data sheet
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20 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
6
voltage
(V)
4
2
send
0
receive
-2
horizontal scale = 62.5 ns/div
5V
5V
5V
300 Ω
RX
SX
TX
send
PCA9601
time (ns)
2 meter
cable
5V
300 Ω
receive
1/ BAT54A
2
RX
SX
TX
GND
002aaf080
Figure 26. Wiring transients limited by a Schottky diode
PCA9601
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21 / 31
PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
11 Package outline
SO8: plastic small outline package; 8 leads; body width 3.9 mm
SOT96-1
D
E
A
X
c
y
HE
v M A
Z
5
8
A2
Q
A
(A 3)
A1
pin 1 index
θ
Lp
1
L
4
e
detail X
w M
bp
0
2.5
5 mm
scale
DIMENSIONS (inch dimensions are derived from the original mm dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D (1)
E (2)
e
HE
L
Lp
Q
v
w
y
Z (1)
mm
1.75
0.25
0.10
1.45
1.25
0.25
0.49
0.36
0.25
0.19
5.0
4.8
4.0
3.8
1.27
6.2
5.8
1.05
1.0
0.4
0.7
0.6
0.25
0.25
0.1
0.7
0.3
0.01
0.019 0.0100 0.20
0.014 0.0075 0.19
0.16
0.15
inches
0.010 0.057
0.069
0.004 0.049
0.05
0.244
0.039 0.028
0.041
0.228
0.016 0.024
0.01
0.01
0.028
0.004
0.012
θ
o
8
o
0
Notes
1. Plastic or metal protrusions of 0.15 mm (0.006 inch) maximum per side are not included.
2. Plastic or metal protrusions of 0.25 mm (0.01 inch) maximum per side are not included.
REFERENCES
OUTLINE
VERSION
IEC
JEDEC
SOT96-1
076E03
MS-012
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-12-27
03-02-18
Figure 27. Package outline SOT96-1 (SO8)
PCA9601
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PCA9601
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Dual bidirectional bus buffer
TSSOP8: plastic thin shrink small outline package; 8 leads; body width 3 mm
D
E
SOT505-1
A
X
c
y
HE
v M A
Z
5
8
A2
pin 1 index
(A3)
A1
A
θ
Lp
L
1
4
e
detail X
w M
bp
0
2.5
5 mm
scale
DIMENSIONS (mm are the original dimensions)
UNIT
A
max.
A1
A2
A3
bp
c
D(1)
E(2)
e
HE
L
Lp
v
w
y
Z(1)
θ
mm
1.1
0.15
0.05
0.95
0.80
0.25
0.45
0.25
0.28
0.15
3.1
2.9
3.1
2.9
0.65
5.1
4.7
0.94
0.7
0.4
0.1
0.1
0.1
0.70
0.35
6°
0°
Notes
1. Plastic or metal protrusions of 0.15 mm maximum per side are not included.
2. Plastic or metal protrusions of 0.25 mm maximum per side are not included.
OUTLINE
VERSION
REFERENCES
IEC
JEDEC
JEITA
EUROPEAN
PROJECTION
ISSUE DATE
99-04-09
03-02-18
SOT505-1
Figure 28. Package outline SOT505-1 (TSSOP8)
PCA9601
Product data sheet
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12 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”.
12.1 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.
12.2 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
12.3 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
12.4 Reflow soldering
Key characteristics in reflow soldering are:
PCA9601
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PCA9601
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Dual bidirectional bus buffer
• Lead-free versus SnPb soldering; note that a lead-free reflow process usually leads
to higher minimum peak temperatures (see Figure 29) 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 8
and Table 9
Table 8. SnPb eutectic process (from J-STD-020D)
Package thickness (mm)
Package reflow temperature (°C)
Volume (mm³)
< 350
≥ 350
< 2.5
235
220
≥ 2.5
220
220
Table 9. Lead-free process (from J-STD-020D)
Package thickness (mm)
Package reflow temperature (°C)
Volume (mm³)
< 350
350 to 2000
> 2000
< 1.6
260
260
260
1.6 to 2.5
260
250
245
> 2.5
250
245
245
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 29.
PCA9601
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Dual bidirectional bus buffer
maximum peak temperature
= MSL limit, damage level
temperature
minimum peak temperature
= minimum soldering temperature
peak
temperature
time
001aac844
MSL: Moisture Sensitivity Level
Figure 29. Temperature profiles for large and small components
For further information on temperature profiles, refer to Application Note AN10365
“Surface mount reflow soldering description”.
13 Abbreviations
Table 10. Abbreviations
Acronym
Description
CDM
Charged-Device Model
ESD
ElectroStatic Discharge
HBM
Human Body Model
2
PCA9601
Product data sheet
I C-bus
Inter-Integrated Circuit bus
I/O
Input/Output
IC
Integrated Circuit
PMBus
Power Management Bus
SCL
Serial Clock Line
SDA
Serial DAta line
SMBus
System Management Bus
TTL
Transistor-Transistor Logic
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14 Revision history
Table 11. Revision history
Document ID
Release date
Data sheet status
Change notice
Supersedes
PCA9601 v.3.1
20220104
Product data sheet
-
PCA9601 v.3
Modifications:
• Added orderable part number PCA9601DPZ.
PCA9601 v.3
20150924
Product data sheet
-
PCA9601 v.2
PCA9601 v.2
20110506
Product data sheet
-
PCA9601 v.1
PCA9601 v.1
20100528
Product data sheet
-
-
PCA9601
Product data sheet
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15 Legal information
15.1 Data sheet status
Document status
[1][2]
Product status
[3]
Definition
Objective [short] data sheet
Development
This document contains data from the objective specification for product
development.
Preliminary [short] data sheet
Qualification
This document contains data from the preliminary specification.
Product [short] data sheet
Production
This document contains the product specification.
[1]
[2]
[3]
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.
15.2 Definitions
Draft — A draft status on a document indicates that 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 in a draft version of a document 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.
Product specification — The information and data provided in a Product
data sheet shall define the specification of the product as agreed between
NXP Semiconductors and its customer, unless NXP Semiconductors and
customer have explicitly agreed otherwise in writing. In no event however,
shall an agreement be valid in which the NXP Semiconductors product
is deemed to offer functions and qualities beyond those described in the
Product data sheet.
15.3 Disclaimers
Limited warranty and liability — 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. NXP Semiconductors takes no
responsibility for the content in this document if provided by an information
source outside of NXP Semiconductors.
In no event shall NXP Semiconductors be liable for any indirect, incidental,
punitive, special or consequential damages (including - without limitation lost profits, lost savings, business interruption, costs related to the removal
or replacement of any products or rework charges) whether or not such
damages are based on tort (including negligence), warranty, breach of
contract or any other legal theory.
Notwithstanding any damages that customer might incur for any reason
whatsoever, NXP Semiconductors’ aggregate and cumulative liability
towards customer for the products described herein shall be limited in
accordance with the Terms and conditions of commercial sale of NXP
Semiconductors.
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.
PCA9601
Product data sheet
Suitability for use — NXP Semiconductors products are not designed,
authorized or warranted to be suitable for use in life support, life-critical or
safety-critical systems or 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
damage. NXP Semiconductors and its suppliers accept 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.
Customers are responsible for the design and operation of their
applications and products using NXP Semiconductors products, and NXP
Semiconductors accepts no liability for any assistance with applications or
customer product design. It is customer’s sole responsibility to determine
whether the NXP Semiconductors product is suitable and fit for the
customer’s applications and products planned, as well as for the planned
application and use of customer’s third party customer(s). Customers should
provide appropriate design and operating safeguards to minimize the risks
associated with their applications and products.
NXP Semiconductors does not accept any liability related to any default,
damage, costs or problem which is based on any weakness or default
in the customer’s applications or products, or the application or use by
customer’s third party customer(s). Customer is responsible for doing all
necessary testing for the customer’s applications and products using NXP
Semiconductors products in order to avoid a default of the applications
and the products or of the application or use by customer’s third party
customer(s). NXP does not accept any liability in this respect.
Limiting values — Stress above one or more limiting values (as defined in
the Absolute Maximum Ratings System of IEC 60134) will cause permanent
damage to the device. Limiting values are stress ratings only and (proper)
operation of the device at these or any other conditions above those
given in the Recommended operating conditions section (if present) or the
Characteristics sections of this document is not warranted. Constant or
repeated exposure to limiting values will permanently and irreversibly affect
the quality and reliability of the device.
Terms and conditions of commercial 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, unless otherwise
agreed in a valid written individual agreement. In case an individual
agreement is concluded only the terms and conditions of the respective
agreement shall apply. NXP Semiconductors hereby expressly objects to
applying the customer’s general terms and conditions with regard to the
purchase of NXP Semiconductors products by customer.
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.
All information provided in this document is subject to legal disclaimers.
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Quick reference data — The Quick reference data is an extract of the
product data given in the Limiting values and Characteristics sections of this
document, and as such is not complete, exhaustive or legally binding.
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 competent authorities.
Suitability for use in non-automotive qualified products — Unless
this data sheet expressly states that this specific NXP Semiconductors
product is automotive qualified, the product is not suitable for automotive
use. It is neither qualified nor tested in accordance with automotive testing
or application requirements. NXP Semiconductors accepts no liability for
inclusion and/or use of non-automotive qualified products in automotive
equipment or applications.
In the event that customer uses the product for design-in and use in
automotive applications to automotive specifications and standards,
customer (a) shall use the product without NXP Semiconductors’ warranty
of the product for such automotive applications, use and specifications, and
(b) whenever customer uses the product for automotive applications beyond
NXP Semiconductors’ specifications such use shall be solely at customer’s
own risk, and (c) customer fully indemnifies NXP Semiconductors for any
liability, damages or failed product claims resulting from customer design and
use of the product for automotive applications beyond NXP Semiconductors’
standard warranty and NXP Semiconductors’ product specifications.
Translations — A non-English (translated) version of a document is for
reference only. The English version shall prevail in case of any discrepancy
between the translated and English versions.
PCA9601
Product data sheet
Security — Customer understands that all NXP products may be subject to
unidentified vulnerabilities or may support established security standards or
specifications with known limitations. Customer is responsible for the design
and operation of its applications and products throughout their lifecycles
to reduce the effect of these vulnerabilities on customer’s applications
and products. Customer’s responsibility also extends to other open and/or
proprietary technologies supported by NXP products for use in customer’s
applications. NXP accepts no liability for any vulnerability. Customer should
regularly check security updates from NXP and follow up appropriately.
Customer shall select products with security features that best meet rules,
regulations, and standards of the intended application and make the
ultimate design decisions regarding its products and is solely responsible
for compliance with all legal, regulatory, and security related requirements
concerning its products, regardless of any information or support that may be
provided by NXP.
NXP has a Product Security Incident Response Team (PSIRT) (reachable
at PSIRT@nxp.com) that manages the investigation, reporting, and solution
release to security vulnerabilities of NXP products.
15.4 Trademarks
Notice: All referenced brands, product names, service names, and
trademarks are the property of their respective owners.
NXP — wordmark and logo are trademarks of NXP B.V.
All information provided in this document is subject to legal disclaimers.
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Tables
Tab. 1.
Tab. 2.
Tab. 3.
Tab. 4.
Tab. 5.
Tab. 6.
Ordering information ..........................................2
Ordering options ................................................2
Pin description ...................................................3
PCA9601/PCA9600 versus P82B96 ................. 5
Limiting values .................................................. 6
Characteristics ...................................................7
Tab. 7.
Tab. 8.
Tab. 9.
Tab. 10.
Tab. 11.
Examples of bus capability ............................. 13
SnPb eutectic process (from J-STD-020D) ..... 25
Lead-free process (from J-STD-020D) ............ 25
Abbreviations ...................................................26
Revision history ...............................................27
Fig. 15.
Fig. 16.
Driving ribbon or flat telephone cables ............ 12
Falling edge of SCL at master is delayed
by the buffers and bus fall times ..................... 13
Rising edge of SCL at master is delayed
(clock stretch) by buffer and bus rise times ..... 14
Rising edge of SDA at slave is delayed by
the buffers and bus rise times .........................14
I2C-bus multipoint application ......................... 16
Propagation SX to TX with VRX = VCC =
3.3 V (SX pull-up to 3.3 V; TX pull-up to 5.7
V) ..................................................................... 16
Propagation SX to TX with RX tied to TX;
VCC = 3.3 V (SX pull-up to 3.3 V; TX pullup to 5.7 V) .....................................................16
Propagation RX to SX (SX pull-up to 3.3 V;
VCC = 3.3 V; RX pull-up to 4.6 V) .................. 17
Diode characteristic curve ...............................18
Transients generated by the bus wiring ...........19
Wiring transients limited by the diodes in
PCA9601 ......................................................... 20
Wiring transients limited by a Schottky
diode ................................................................21
Package outline SOT96-1 (SO8) .....................22
Package outline SOT505-1 (TSSOP8) ............23
Temperature profiles for large and small
components ..................................................... 26
Figures
Fig. 1.
Fig. 2.
Fig. 3.
Fig. 4.
Fig. 5.
Fig. 6.
Fig. 7.
Fig. 8.
Fig. 9.
Fig. 10.
Fig. 11.
Fig. 12.
Fig. 13.
Fig. 14.
Block diagram of PCA9601 ...............................2
Pin configuration for SO8 ..................................3
Pin configuration for TSSOP8 (MSOP8) ........... 3
Equivalent circuit at SX/SY ............................. 10
VOL as a function of junction temperature
(IOL = 0.3 mA) ................................................ 10
VOL as a function of junction temperature
(IOL = 3 mA) ...................................................10
VIL as a function of junction temperature;
maximum and typical values ........................... 10
VIH as a function of junction temperature;
minimum and typical values ............................ 10
VCC bus release limit over temperature;
maximum values ............................................. 11
Current sourced out of SX/SY as a function
of junction temperature if these pins are
externally pulled to 0.4 V or lower ...................11
Typical SX/SY current versus LOW-level
output voltage ..................................................11
Interfacing a standard 3 mA I2C-bus or
one with TTL levels (e.g. SMBus) to higher
voltage or higher current sink (e.g. Fastmode Plus) devices .........................................11
Galvanic isolation of I2C-bus nodes via
opto-couplers ...................................................12
Long distance I2C-bus communication ........... 12
PCA9601
Product data sheet
Fig. 17.
Fig. 18.
Fig. 19.
Fig. 20.
Fig. 21.
Fig. 22.
Fig. 23.
Fig. 24.
Fig. 25.
Fig. 26.
Fig. 27.
Fig. 28.
Fig. 29.
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PCA9601
NXP Semiconductors
Dual bidirectional bus buffer
Contents
1
2
3
4
4.1
5
6
6.1
6.2
7
7.1
7.1.1
7.1.2
7.2
7.3
7.4
General description ............................................ 1
Features and benefits .........................................1
Applications .........................................................2
Ordering information .......................................... 2
Ordering options ................................................ 2
Block diagram ..................................................... 2
Pinning information ............................................ 3
Pinning ............................................................... 3
Pin description ................................................... 3
Functional description ........................................3
Static level offset card side ................................3
Fast-mode operation ..........................................4
Fast-mode Plus operation ................................. 4
High drive, long distance side ........................... 4
Connections to other bus buffers .......................5
Comparison of PCA9601/PCA9600 and
P82B96 .............................................................. 5
8
Limiting values .................................................... 6
9
Characteristics .................................................... 7
10
Application information .................................... 11
10.1
Calculating system delays and bus clock
frequency ......................................................... 13
10.2
Negative undershoot below absolute
minimum value ................................................ 17
10.2.1
Example with questions and answers ..............18
11
Package outline .................................................22
12
Soldering of SMD packages .............................24
12.1
Introduction to soldering .................................. 24
12.2
Wave and reflow soldering .............................. 24
12.3
Wave soldering ................................................ 24
12.4
Reflow soldering .............................................. 24
13
Abbreviations .................................................... 26
14
Revision history ................................................ 27
15
Legal information .............................................. 28
Please be aware that important notices concerning this document and the product(s)
described herein, have been included in section 'Legal information'.
© NXP B.V. 2022.
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: 4 January 2022
Document identifier: PCA9601
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