【TI Live FAQ】CAN SIC (Signal Improvement Function) Technology

EEWORLD社区

【TI Live FAQ】CAN SIC (Signal Improvement Function) Technology [Copy link]

 

Live Topic: CAN SIC (Signal Improvement Function) Technology Live

Content introduction:
From powertrain, to advanced driver assistance systems, to infotainment and safety, electronic control units (ECUs) such as controller area networks (CAN) are needed in vehicles to perform different types of electromechanical functions. In this webinar, we will discuss what is CAN SIC (Signal Improvement Function) technology? Why and when should you use it in your automotive and industrial systems. The live agenda is as follows:
1. CAN SIC technology overview
2. Our CAN SIC product portfolio
3. How to add CAN SIC to your design

Live lecturer: Kankan Wang｜Transceiver Product Marketing Engineer, Texas Instruments

Excerpt from the Live FAQ:

1. Is CAN SIC a hardware technology or a software technology?
Our SIC practice is actually implemented at the IC level, so it is a hardware technology and is not related to software. In the process of developing your system, when you switch from a traditional CAN transceiver to a traditional SIC transceiver, as we have just discussed, there is no need to modify any software or hardware and you can use it directly. In this way, CAN SIC is very convenient for us to use, and the development process is also very simple.

2. Is the waveform of the CAN bus oscillation caused by impedance mismatch?
The main reason is that we have two reasons. One is the topological structure. If it is a more traditional bus topology, the impedance matching of the transmitter and the receiver can be relatively simple. However, in a more complex star topology, the difficulty of impedance matching of this topology will be greatly increased. Because we don't know which point is sent to which point is the receiving point, and at the same time, its impedance will change greatly in the process of its signal from dominant to recessive and from introduction to dominant. At this time, if the impedance is not matched, this kind of signal oscillation will occur, which will affect our correct interpretation of the signal.

3. What peripheral devices need to be added?
In fact, when we switch from the traditional CAN transceiver to the CANCAN SIC, we do not need to add any external devices. Because the pins of its transceiver are fully compatible, it can be directly switched and used without any software and hardware modifications.

4. What is the maximum operating temperature of the CAN SIC transceiver?
Generally speaking, the ambient temperature is 125 degrees. The maximum temperature that the chip can withstand is 150 degrees, which fully meets the needs of the automotive application market and various industrial high-temperature application markets.

5. Does CAN SIC technology require TI devices at both ends to be implemented?
This depends on our CAN application scenario. If our application scenario is a more complex topology, such as the star topology we mentioned just now, and the data rate is relatively high, 2 megabits or 5 megabits, then if both the transceiver and the receiver are CAN SIC, of course the effect is the best, in this way there is no such camp process, but if one end is CAN SIC and the other end is a traditional CAN or CAN FD transceiver. In this process, because we cannot determine which point is the sending point and which point is the receiving point, there may be a bus oscillation scenario. But if the other end is from another supplier, if they have CAN SIC from another supplier, then they can communicate normally without any problems.

6. What is the maximum data rate that can be supported now? Can it reach 10 Mbps?
We just mentioned that the latest CAN SIC transceiver of Texas Instruments can support a maximum data rate of 8 Mbps. In our CIA standard, the maximum rate is 5 Mbps. So now in this industry or standard, there is no demand for a rate of 10 Mbps. So our latest CAN SIC transceiver can support up to 8 Mbps. If our customers have some needs in the future, as the standard continues to advance, we will also have CAN transceivers with higher data rates.

7. What is the main difference between CAN FD and CAN SIC?
I will explain here that CAN SIC is actually a new indicator of the CAN FD standard. This indicator mainly improves the problem of aging bus vibration caused by CAN FD under complex topology, especially at our 2M or 5M working speed. If the Top structure is a star structure or other structure, the traditional CAN FD's timing time indicator is difficult to meet the stability of our bus in a short time, so bus vibration will occur at this time. However, the CAN SIC transceiver, first of all, meets the latest CIA601-4 indicators. In its timing process, timing control, and transmission delay, it meets our latest standards. Secondly, our CAN SIC devices have this active bus vibration suppression function in the design, thereby achieving the goal of reducing bus vibration and improving the working speed. Therefore, CAN SIC is an indicator designed for CAN FD to be better at high speeds.

8. Is the CAN FD link layer protocol still compatible?
Currently, the CAN SIC indicators meet or exceed all ISO and ICI standards currently on the market or defined by international organizations, so its indicators are fully compatible and can even exceed the indicators set by these international organizations.

9. What are the special requirements for CAN FD or CAN SIC routing?
If you can pay attention to the data sheets of various CAN transceivers, if you download the data sheets of various transceivers from TI's official website, there will be some guiding summaries in the last part of the data sheets. How should you do it when designing routing? For example, the protection circuit should be as close to the interface as possible, for example, the grounding resistor can be allocated to two resistors, and then the middle point is grounded. These specific technical details have relevant guidance in the last part of the data sheet, and you can do some further research based on this part.

10. Are Texas Instruments' CAN SIC transceivers, or Texas Instruments' CAN transceivers, compatible with CAN transceivers from other suppliers or other semiconductor companies?
Now CAN transceivers are basically pin-compatible. Some of the transceivers we just mentioned have 8 pins, and some have 14 pins. These transceiver pins are compatible and can be used together.

11. What is the comparison between TI's CAN transceiver and other suppliers' CAN transceivers?
First of all, all TI's CAN transceivers are based on TI's own technology in terms of design, production and semiconductor technology. For example, the semiconductor technology of all our transceivers is developed by TI itself, so our design team, quality control team and production team know very well how to achieve the best quality and maximum efficiency in the design and production process.
Secondly, TI has a certain amount of common experience in the field of CAN transceivers. We have many previous generation products that everyone may be familiar with. Our latest CAN transceiver is our TCAN transceiver series, including the CAN SIC trigger introduced to you today. Therefore, TI has a very long history in CAN transceivers, and our accumulated experience can ensure that everyone can have great confidence in our products.
Another point is that the production of TI's CAN transceivers is also completed in TI's own wafer fab and packaging and testing plant, so we have certain advantages in quality control and production capabilities. Many of our CAN transceivers can be produced in multiple wafer factories and multiple packaging and testing factories, with mutual backup, so we have an absolute advantage in supply capacity. I think everyone knows that the supply of the entire semiconductor industry is very tight now. Of course, Texas Instruments' supply is also limited to a certain extent. However, relatively speaking, TI's supply is still better than that of some other semiconductor manufacturers, mainly because all production is completed by Texas Instruments itself, and we have better control over this process.

12. Will the CAN bus be replaced by the Ethernet bus?
In fact, I personally think that different application scenarios in the automotive industry may have different bus requirements, different data rates, and different bus requirements. For example, some netizens are asking about the relationship between the LIN bus and the CAN bus. As you know, the LIN bus is a bus with a relatively low transmission rate, and the LIN bus is a single-ended signal, so the LIN bus is generally used in some application scenarios that do not require high continuous security.
Let's take cars as an example. For example, the door locks in the car and the rising and falling of the window glass in the car are generally formulated and managed by the LIN bus. However, in the car, most of the control scenes and mechanical controls are generally managed by the CAN bus, and different buses have different speeds. We just mentioned Ethernet, which is generally used at higher speeds. For example, if the speed is relatively low, we have the LIN bus, and then in the range of 1 megabit to 5 megabits or now to 8 megabits, we have CAN FD and CAN SIC. In addition, international organizations have been formulating the next generation of CAN indicators, which may increase the speed of our CAN bus to 10 megabits or more. There will be some other indicators in the future. Therefore, according to our different application scenarios and different speed requirements, we will have corresponding different bus forms and different protocols that can be used with CAN.

13. Where is the signal improvement of CAN SIC?
I believe that through the introduction just now, everyone may have a preliminary impression of the signal improvement of CAN SIC. Here I will mainly explain that its signal improvement is mainly to improve the driving ability of the transmitter of the transceiver. In the design of its driving circuit, it adds a unique function. When the state of the bus it detects changes, it will automatically turn on the ringing suppression circuit accordingly, so that our bus tends to be stable, and its bus does not cause zero vibration at the time of sampling, so as to improve its accuracy.
In addition, at the receiving end of the transceiver period, we have higher requirements for the propagation delay of the data, and reduce the parameter performance of the propagation delay of the data, so as to meet the correctness of our sampling. So it is an improvement of the CAN transceiver in hardware, but all these performance improvements are achieved by hardware. For our use, no software or hardware changes are required. Just like many netizens asked whether the TCAN1042 used before can no longer be used, this is also relative. If the data rate of your application scenario may not be very high, a few hundred kps or one megabyte or less, and the bus is relatively simple, for example, the bus form we mentioned just now is relatively simple, and both ends of the transmitter and receiver are going to the transceivers at both ends, and there are such scenarios as impedance disconnection resistance. At this time, our original TCAN1042 or our latest TCAN1044 can continue to be used without any problems. However, if you find that when you want to improve the data combing of your application scenario, it causes this bus oscillation and error or other scenarios, then you can consider the CAN SIC transceiver we mentioned today, so that under more complex bus conditions and with higher-speed data transmission requirements, you can get better results.

14. Are there any low-power CAN transceivers?
Some of the TCAN transceivers we mentioned just now, such as TCAN1462, TCAN1463, and TCAN1466, all have low power consumption. We can explain that in automotive applications, we often use this standby mode, the low-power mode Standby, because in the standby low-power mode, its transmitter and receiver are both turned off, so it can greatly reduce its power consumption when it is low power. The TCAN1462 we mentioned just now has the Standby low-power mode, so today we will introduce to you several of TI's latest CAN SIC transceivers with low-power modes.

15. TCAN1042 and TCAN1642 are interchangeable. Let me answer this. 1042, first of all, the 1042 series of CAN transceivers does not have the CAN SIC function we mentioned today. It is a more traditional CAN transceiver. However, as for these two part numbers, they can be interchanged with each other, their pins are fully compatible, and their performance is very similar. However, I also mentioned earlier that because the semiconductor process used by TI's CAN transceivers is completed by TI itself, our designers have a clear and definite understanding of our process, so the performance of the products we design can be said to be better than that of CAN transceivers of other semiconductor companies on the market.
To give a simple example, in our automotive application scenarios, we generally have to pass various EMI tests. We also compare the CAN transceivers on the market. We can use CAN to TCAN transceivers. Due to its strict requirements for manufacturing process, production process and final testing, the symmetry of the two signals CAN h and CAN l on the two buses of TCAN is very good. In this way, our overall anti-interference ability is better than that of many other semiconductor companies' products on the market. So although they are pin-compatible and can be replaced with each other, our TI CAN transceiver, due to its design capabilities, process technology, production technology and testing technology, the performance of our low-carbon products is better than that of other local companies' solutions on the market.
In addition, we can also mention the latest CAN SIC transceiver, which can also replace our previous generation TCAN1042 or other CAN transceivers. They can be directly replaced without any problems.

16. Is the communication rate of CAN SIC variable? Is the design complicated?
We just mentioned that the latest TCAN1462 supports a maximum data rate of 8 Mbps. Here you can see that we are talking about the highest rate. If the speed requirements of your application scenario are relatively low, such as one to two Mbps or a few hundred kilobytes, you can also use CAN SIC transceivers without any problems. However, the advantages of CAN SIC transceivers are mainly reflected in the scenarios of higher-speed communication under complex loop structures. Therefore, in the case of relatively low rates, it may be easier to choose, with multiple data options and multiple solutions to choose from. But if your application scenario requires higher data, the advantages of the CAN SIC we improved today will be more obvious.

17. What should be noted for compatibility with traditional CAN?
As we just mentioned, CAN SIC and traditional CAN transceivers are pin-compatible, so they can be directly replaced without any changes in the design process.

18. For CAN SIC and CAN SD networks, if some nodes do not support SIC connection, can they only transmit data in accordance with CAN FD? Let
me explain to you here that CAN SIC has made some stricter regulations on its timing for those compatible with CAN FD, so that better data transmission can be carried out under high data conditions without bit errors and axis oscillation. So if we have CAN SIC and traditional CAN FD on a bus, if at this time we have to look at our propagation rate, if the rate is not very high, such as two megabytes or lower, if our bus form is not very complicated, then there is no problem with mixing. But if our bus is like the dual crystal structure mentioned just now, or our data rate is also relatively high at this time, 2 megabytes or 5 megabytes, then the traditional CAN FD may cause bit errors during the sending and receiving process. If the sending is completed by CAN SIC, the bit error rate will be much lower relatively speaking.

19. TI has various buffs. Is it okay to just choose the highest voltage-resistant product?
The CAN SIC transceivers of the TCAN146 series mentioned today support a bus fault protection voltage of ±58 volts, which means that if a voltage of 58 volts or less is short-circuited to our CAN buff from the outside, the CAN bus is protected and there will be no hardware damage. The internal protection circuit of the CAN SIC transceiver can achieve short-circuit protection within 58 volts. However, if the short-circuit voltage of the short line outside is high, higher than 58 at a time, it may cause some damage. However, in addition to the TCAN146x series we talked about today, TI also has some transceivers that support higher bus protection. For example, the well-known TCAN1042x series supports ±70 volt lifetime protection, which can achieve a higher protection level.

20. How much ESD voltage can it withstand?
In the brief description just now, we also mentioned the ESD of several devices. All the devices we mentioned today have ESD protection functions, including the more common IEC ESD and HBM mode ESD. What’s more important is that all the devices mentioned today are automotive-grade, and they must meet various types of indicators in the automotive industry, including ESD and electromagnetic interference. So if our application scenario is in the automotive grade case, the approvals mentioned today can meet this requirement.

21. What temperature range is the TCAN146 series with signal improvement function mentioned today used for?
I mentioned earlier that our indicators are defined at -40~150 degrees. In terms of node voltage, if the temperature range to the node is -40~150 degrees, it can meet its normal operating temperature range.

22. How many different packages and sizes have been launched for the several CAN transceivers with signal improvement functions mentioned today?
I would like to explain this to you. The most common CAN transceivers on the market are still the more traditional SOIC. For example, the 8-pin ones are generally around 5×4 mm, and the 14-pin ones are about 6×8 mm SIC packages. In addition to the more traditional SOIC packages, TI's CAN transceivers have other small package options. For example, the device we mentioned today has a 3×3 mm v so n, that is, a package without pins, and a smaller sot package of 2.9×1.6 mm.
This SOT package is relatively small in size, so when we do the layout design, we can consider putting the SOT and SOIC packages together, and put the SOT package in the SOIC layout in the layout design. In this way, in our future large-scale production process, we can choose both SOIC and SOT packages, which will have more flexibility in supply and procurement.
So the several transceivers we mentioned today have both traditional SOIC packaging and our smaller SOT packaging.

23. Has the CAN SIC transceiver passed the automotive-grade certification?
Today we introduced several CAN SIC transceivers, all of which have passed the AEC q100 automotive-grade certification and fully meet the following indicators of the automotive Q100 standard. In addition, the various CAN SIC transceivers mentioned today have also passed different automotive-grade test standards in various automotive markets, such as some ESD tests and some anti-interference tests. The several transceivers mentioned today took into account the various automotive-grade certifications that will need to be passed in the future, or certifications for other application scenarios, during the design stage. So the market we are targeting is the automotive market and the industrial market, so all these materials have passed the automotive-grade certification.

24. Does the chip support remote wake-up?
This function is included in the latest CAN transceivers. Several chips we mentioned today support remote wake-up. In addition, the chip we mentioned just now is called TCAN1463. This material not only supports remote wake-up, but also has an enable pin. During the design process, this enable pin can be used to control some external circuits, such as the DCDC link of the external power supply management. It can turn off the external power supply through the pin, and the entire system can be in low-power mode. When it is remotely awakened, it can turn on the power supply of the external power management chip, so that the entire system returns to normal operation. In this mode, power consumption can be minimized, which is also a unique function of the TCAN1463 material we mentioned today.

25. What topologies does CAN SIC only need to support?
In fact, in various applications, it is inevitable that there will be different topologies, such as ring-shaped buses. Let's first mention the star structure. The biggest advantage of CAN SIC mentioned today is that it can achieve better results in various buses and various main line conditions. Therefore, the general bus and various bus types can be supported by the CAN SIC transceiver mentioned today.

26. What is the transmission rate of CAN SIC?
Generally speaking, the CIA standard defines data rates of 2 Mbps and 5 Mbps. Today, we will talk about several new CAN SIC transceivers in the TCAN series, which can support data rates up to 8 Mbps.

27. TI CAN SIC is applied to automotive scenarios because ordinary CAN or CAN FD does not meet the new automotive scenarios. In fact, it can be said that in the process of using CAN, various designers have many expectations to achieve higher data transmission. However, based on traditional CAN or CAN FD transceivers, many designers will find in the design and testing process that when the data is increased to 2 megabytes or 5 megabytes, it will cause relatively large noise, and then the bus will not be stable, and there will be such an oscillation scenario. At this time, due to the bottleneck of the technical capabilities of the existing transceivers, many of our designers are unable to use higher data rates for communication. The CAN SIC transceiver mentioned today is to solve this problem, which can enable our designers to have only 2 megabytes and 5 megabytes of applications, and faster data transmission, so that our application scenarios can be expanded.

28. What is the difference between TI's SIC and other technologies?
Let me explain to you here. In the CIA standard process we just mentioned, it actually did not specify how this SIC is implemented. It just said that there are more stringent instructions on the timing control of the transceiver. As long as these more stringent indicators can be met, it can be used in the application scenario of SIC. In the design process of some of TI's own devices, we have our unique technology or some patents in it, which can reduce component vibration at relatively high speeds. I think if other CAN transceivers want to meet the CIA standard, they certainly have their own unique design concepts and design technologies, but in general, no matter whose CAN transceiver, everyone has to meet our CIA601-4 SIC standard, so that it can be fully expanded to various application scenarios. But specifically, there may be various types of semiconductor companies' CAN transceivers, and there are some unique features in them. For example, the EMI effect of TI's CAN transceiver that I just mentioned is relatively good. There may be an application scenario where you can achieve a good EMI effect without using some external components. This is also because TI has its own unique technology in its own design and manufacturing, as well as in the process.

29. Can two CAN SIC transceivers working at different voltages be directly connected and communicated?
The TCAN146x series transceivers we mentioned today are all powered by 5 volts. The main reason is that in automotive applications, our standards are defined below 5 volts, so all the various TCAN transceivers mentioned today are working under the 5 volt power supply scenario. If in other application scenarios or using CAN transceivers from other semiconductor companies, if in the same application scenario, they should also be powered by 5 volts, so they can be used interchangeably.

30. What is the maximum voltage range of the CAN bus of TCAN1462?
The CAN transceiver of TCAN1462 mentioned today supports ±58V bus fault protection and can work normally within the bus voltage range of 58V or less without any corresponding damage.

31. Can TCAN1463 be used for 15V voltage?
Our TCAN1463 is a 13-pin CAN transceiver with wake-up function. It has an external power supply voltage that can directly support 4.5V to 40V. So if it can be used in automotive applications, it can directly reach 40V when powered by a car battery. This should meet the 15V voltage standard mentioned in our question.

32. Can it be used for tunnel street light control?
In fact, in addition to the automotive application scenarios mentioned above, CAN transceivers can also be used in other application scenarios, including industrial automation lighting or other scenarios. According to the requirements of its own characteristics, communication rate requirements, communication distance requirements, or whether there is a need for an arbitration mechanism and a Trojan horse judgment mechanism, if there is a need for such a mechanism, or if you want to use this feature, you can use a CAN transceiver.

33. What are the advantages or differences between CAN and RS485?
These two interface modes are actually used in industrial and automotive application adjustments. At that time, we mentioned that CAN or LIN is used in many automotive scenarios. In fact, RS485 transceivers can also be used in automotive scenarios. Texas Instruments also has several RS485 transceivers with automotive certification, but there are also slight differences in actual application scenarios, because RS485 is just a physical measurement definition. It does not have such a data link layer, application layer or higher level definition, so it is completely just an electrical characteristic defined at the physical layer. When we designers use it, we can freely define some indicators of the data layer, data link layer or application layer. CAN is relatively different. CAN has corresponding indicator requirements whether it is at the physical layer, data link layer or higher application layer, so it has built-in error diagnosis and arbitration functions, which is different from 485.
In addition, the transmission data rate of CAN, as we mentioned just now, is more common, but the maximum is 1 Mbps, 2 Mbps, 5 Mbps, and the 8 Mbps transceiver we mentioned today. The transmission speed of RS485 may be wider. It can support, for example, the RS485 that Texas Instruments currently uses, which supports a maximum transmission rate of 50 Mbps. Therefore, according to different application scenarios, different transmission distances, different data rates, and requirements for signal indicators, you can choose the corresponding protocol, whether it is CAN bus or RS485.

34. Bus fault voltage protection. If the total bus voltage is continuously short, can it support a higher fault voltage?
The bus fault protection voltage we mentioned refers to the normal energy-off protection, which means that it can be protected for a few seconds or longer. If it is transient protection, it is more inclined to ESD or other protection modes. However, according to the ±58 volt requirements listed in our data, we recommend that it is within the ±58 volt voltage range as much as possible, so that our bus and our transceiver will not be damaged.

35. Can CAN SIC only be used in automobiles?
Today we mentioned several transceivers that support CAN SIC, all of which have passed automotive regulations and can be fully used in automotive application scenarios. However, it can also be used in non-automotive application scenarios, such as industrial communications or other application scenarios. The transceivers that support CAN SIC mentioned today are all OK, but the transceivers we mentioned can meet higher-level automotive regulations, but it can also be used in other application scenarios without any problems.

36. Some netizens are asking whether TCAN1463 is powered by a battery.
We just briefly answered this question. As you can see, the TCAN1463 we mentioned has a power supply pin that supports a voltage range of 4.5V to 40V, which can be used to directly power the battery.

37. Does each terminal of the star bus need to match the resistor?
In fact, I also understand that in the actual design process, it is difficult to match the resistor for each terminal in the actual application process. In fact, this is one of the reasons for signal reflection and bus oscillation. If a traditional CAN transceiver is used, it does not have this kind of oscillation suppression circuit. In the absence of a central resistor, it is easy to cause main line oscillation, and then some bit errors are generated. However, through the CAN SIC transceiver we mentioned today, because it has the function of bus oscillation suppression, it can greatly improve the problem of bit error rate in the absence of terminal electronics.

38. CAN SIC is an indicator of CAN FD. Do all CAN FDs have to meet the CAN SIC requirements?
I think the answer is no, because the CAN FD standard is earlier than the CAN SIC standard. Many CAN FD standards may be released around 2016, and our latest CAN SIC definition standard will be released later. So now, whether it is Texas Instruments or other manufacturers, manufacturers have CAN FD deep diggers, but many of them not only have CAN SIC, CAN SIC is our new transceiver that meets the SIC standard. This is probably the process.

39. Does the CAN SIC port need ESD protection measures?
Our latest TCAN transceiver has ESD protection with certain specifications. Different indicators, different pins, and different specifications have different requirements. Therefore, we can choose the corresponding CAN transceiver according to our paper.

40. What is the difference between TCAN1462 and TCAN1462V?
This can also be explained. First of all, both of these materials are 5V powered CAN transceivers, and their indicators are very close. TCAN1462V has a pin. When the pin is set to different voltages, the logic voltage level of its data communication is different. For example, our external CAN controller is powered by 3.3 volts. At this time, set the Vout pin of TCAN1462V to 3.3 volts. TCAN1462V can use the CAN controller to communicate directly without using the external level conversion process. The Vout pin is the main difference between TCAN1462V and another TCAN1462.

41. Does it support electrostatic protection?
Of course, I have mentioned it many times. All TCANs mentioned today, including the latest CAN transceivers from Texas Instruments, are equipped with traditional HBM ESD protection and IEC ESD protection.