Ten Daily Electronic Common Sense-Section 86

What is the error management logic responsible for?

Error management logic is responsible for error management of transport layer modules. It receives error reports from BSP and informs BSP and IML for error statistics.

What aspects should you consider when selecting ferrite materials?

• Frequency of unwanted signal to be suppressed
• Radiated or conducted energy source
• Environmental conditions (increase in temperature can reduce overall impedance and performance)
• Circuit impedance of source and load
• Amount of attenuation required
• Allowable space size on PCB
• Impedance presented by the ferrite material to the circuit
• Permeability values in the selected operating frequency range
• Changes in impedance due to changes in core size, shape or length
• Bias (the flow through the material current) will reduce the impedance to invalidate the point of failure
• Additional “undesirable” signal attenuation occurs when either AC or DC current flows through the element
• Additional winding on the bead or core increases shield impedance (however, reduces spectral bandwidth performance)

What points should I pay attention to when setting the multi-speed speed of the inverter?

• When setting the multi-stage speed of the inverter, you need to pay attention to the following points:
  1. Each parameter can be set in the range of 0~400Hz, and the parameter value can be modified during the running period.
  2. The parameters of multi-step speed can be set during PU operation or external operation, but only in external operation mode or Pr. When 79=3 or 4, it can run multi-speed, otherwise it cannot.
  3. Multi-stage speed has priority over main speed, but there is no priority for setting between parameters.
  4. When using Pr. 180～Pr. 186 When the terminal function is changed, its operation will change.

What is ASD?

The full name of ADS is ARM Developer Suite, which is a new generation of ARM integrated development tools launched by ARM. Now the latest version of ADS is 2.5.1, which replaces the earlier ADSl.1 and ADSl.0. In addition to being able to be installed under Windows NT4, Windows 2000 operating systems, it also supports Windows XP and Windows Me operating systems.

What are the characteristics of text displays?

The text display can only display numbers, characters and Chinese characters, but cannot display graphics.
Text display TD 200, TD 200C and TD 400C are small monitoring devices tailored for S7-200, and are configured with the programming software STEP 7-Micro/WIN of S7-200.
With the exception of the text display, other HMIs from Siemens are configured with WinCC flexible.  
The above-mentioned TD equipment can be configured with 80 alarm messages and 64 process pictures. Using PPI communication, there is a password protection function. The time and date can be set for a CPU with a real-time clock. Check and change the RUN/STOP operation mode of the CPU, and force the digital input/output points.

What are the main differences between CPLD and FPGA in application?

1. FPGA is “sequential rich” type, which is more suitable for completing sequential logic. CPLD is “logic-rich” type, which is more suitable for completing various algorithms and combinational logic. That is, FPGA is more suitable for the structure with abundant flip-flops, while CPLD is more suitable for the structure with limited flip-flops and abundant product terms. Therefore, CPLD is suitable for designing complex combinational logic such as decoding. The manufacturing process of FPGA determines that the number of LUTs and flip-flops contained in the FPGA chip is very large, and the integration is higher. Therefore, FPGA is suitable for situations where a large number of flip-flop circuits are used in the design.
2. FPGA is gate-level programming, and distributed interconnection is used between LABs. FPGAs are primarily programmed by changing the routing of the interconnects. And CPLD is logic block level programming, and its logic block interconnection is lumped. CPLDs are programmed by modifying logic functions with fixed interconnected circuits. And because the CPLD has a dedicated connection, each macrocell is connected. The delay of the signal to each macrocell is the same and the delay is the shortest, so CPLD has greater time predictability than FPGA. Therefore the CPLD can predict the maximum pin-to-pin delay time.
3. CPLD is mainly based on E2PROM or FLASH memory programming. The advantage is that the programming information is not lost after the system is powered off. And no external memory chip is needed, and it is easy to use. FPGAs are mostly based on SRAM programming. The advantage is that it can be programmed any number of times and can be programmed quickly on the fly. Enables dynamic configuration at the board and system level, so the FPGA can reconfigure the hardware. The disadvantage is that the programming information needs to be stored on the external memory. At each power-up, programming data needs to be written to the SRAM from the device’s external memory or from a computer. The use method is complicated, and the programming data information is lost when the system is powered off. In short, FPGA and CPLD have their own characteristics and advantages. Both of them have made great progress in programmable logic device technology. Therefore, when choosing CPLD or FPGA, the best choice can be made according to different technical requirements and specific applications.

What is the development of battery-powered portable devices?

Portable devices powered by batteries are constantly developing in the direction of high speed, miniaturization and portability.

Microwave device selection for high-power wireless routers：

Among the many analog device manufacturers, the product performance of Skyworks, RFMD, SiGe, SST and Microsemi is particularly outstanding. Moreover, they all have certain advantages in terms of cost. This time, we will focus on the high-power microwave devices of these five companies. 
Skyworks: Skyworks is an industry-leading wireless communication semiconductor supplier focusing on RF and complete communication system solutions for mobile communication applications. Provide various front-end modules, RF subsystems and mobile systems to mobile phone, wireless network and communication infrastructure customers. Skyworks is headquartered in Woburn, Massachusetts, with administrative offices in Irvine, California. And has design, engineering, manufacturing, marketing, business and service teams in North America, Europe, Japan and Asia Pacific. 
RFMD: RFMD is a world-class provider of design, manufacture and application solutions for high-performance wireless systems for mobile communications. RFMD’s power amplifiers, transmission modules, cellular transceivers and system-on-chip (SOC) solutions facilitate the mobility of global communications. Enhanced connectivity and support for advanced features in current and next-generation mobile phones, cellular base stations, wireless local area networks (WLAN), and global positioning systems (GPS). 
SiGe: SiGe Semiconductor (SiGeSemiconductor, Inc) is a global leading supplier of radio frequency (RF) solutions for wireless systems in GPS, Bluetooth, Wimax, WirelessLan, etc. SiGe Semiconductor is headquartered in Ottawa, Canada, and its R&D department is located in Cambridge, UK. The members were originally affiliated with the National Research Institute of Canada, specializing in semiconductor processes. After becoming an independent company, it focuses on the development of RF products with silicon germanium process. 
SST: SST is a leading manufacturer of flash memory (Flash) technology with its own ultra-fast flash technology. Produces and sells a variety of non-volatile memory solutions that are widely used in digital consumer products, networking, wireless communications and network computing markets. SST’s products include high-function flash memory, high-capacity flash storage products and integrated single-chip flash memory microcontrollers. 
Microsemi: Microsemi is a global supplier of power management, power conditioning, transient suppression and RF/microwave semiconductor devices. The company manufactures highly reliable analog ICs and discrete semiconductor devices. It is used in satellite, telecommunication, computer/peripheral, military/aviation, industrial/commercial, medical and other fields.

What problems are sometimes encountered during the use of the waterfall model?

1. Actual projects rarely proceed in the order given by the model. While linear models can allow iteration, they are indirect. Changes during project development can cause confusion.
2. It is often difficult for users to clearly give all requirements. While linear models require this, they cannot yet accept the uncertainty that naturally exists at the start of many projects.
3. Users must be patient. A working system is not available until late in the project’s development. Big mistakes can be catastrophic if they are not discovered until the running program is checked.
4. Developers’ time is often unnecessarily delayed. In a real project, the linear nature of the waterfall model can lead to a “blocking state”. Some project team members have to wait for other members of the team to complete their dependent tasks first.

What are the components of the dual heat pipe system?

The dual cooling pipe system consists of 3 parts: dual cooling pipes, dual cooling plates and metal brackets.