What is Altium? Altium is a PCB design tool, PCB stands for Printed Circuit Boards and the designing process for a PCB include: Schematic capture, Layout, SPICE simulations, Library and footprint creation, Part tracking, sourcing and revision tracking of both the components used in the design and design itself. It is like git for PCBs and Altium provides tools and resources for all parts of the PCB design workflow.The Altium designer comes with an easy-to-use interface that has lots of features for the PCB designer, like revision control and hot-keys. Altium has 4 SoftwareAltium DesignerAltium NexusAltium Circuit StudioAltium Circuit Maker Previous Next All these software provide a robust framework for the PCB designer to acquire skills of a cross-function multidisciplinary role, because PCB design requires understanding and knowledge of electronic, electrical, and mechanical theory and implementation mechanisms like testing equipment used, designing equipment, and of course manufacturing. Altium software offers the user the ability to interact and collaborate with the mechanical, electronic, and electrical designer through various tools integrated into the software which provide a seamless and robust framework for the designer. Figure 1 Altium 3D mechanical rendering. With the increase in remote working Altium software also offer cloud storage for saving projects, rendering projects, and even saving and running SPICE simulations!
UART stands for Universal Asynchronous Receiver/Transmitter. It communicates asynchronously. UART can work with different types of serial protocols that involve transmitting and receiving serial data. UART is not like other protocols it is a physical circuit built-in microcontroller or a dedicated IC. In old computer systems, devices like mouse or printer Uart was used for communicating although USB has replaced UART in recent devices still almost Microcontroller are using UART. In this blog, we will cover every concept about UART which will help you in better understanding this communication protocol. Modes of communication in UART UART has 3 different modes for communication: Simplex: Simplex data transmission means that data communication is one-way only. Full-duplex: Full–duplex data transmission means that data can be transmitted in both directions on a signal carrier, Simultaneously. Half-duplex: Half–duplex data transmission means that data can be transmitted in both directions on a signal carrier, but not at the same time. HOW DOES IT WORK? Communication between 2 UARTs UART is a single-master, single-slave protocol, where one device is set up to communicate with only one partner. UART uses only two wires for communication, one is for transmitting data called Tx pin and one is for receiving data called Rx pin. In UART, Master takes input from CPU or any other peripheral device in the parallel form then transmits the bits into serial form asynchronously to Rx [receiver], and then the slave or the receiving device transforms the data bits into parallel again with its controlling device. [ please refer blog1 for serial and parallel communication] UART transmits data in the form of packets which includes a start bit, data frame, parity bit, and stop bit as shown in the following diagram. Start Bit To start the transmission, the transmitter sends the 0 bit to the receiver or we can say that the clock pulse which is usually set at high voltage in a not transmitting state changes its voltage from high voltage to low voltage for one clock cycle. This clock pulse alert the receiver about the bits and then the receiver starts receiving the data bit by bit. Data Frame Data Frame contains the main information about the data. Length of the data frame can vary between 5-8 bits if the parity bit is in use, if not then it can be 9 bits long as well. The transmitter sends the data bit by bit to the receiver with a pre-defined baud rate. While transmitting data there is some delay which depends on the baud rate. The baud rate is a measure of the number of bits per second that can be transmitted or received by the UART. Parity bit The parity bit is used for detecting the error in the main data. How does parity work? A number of 1’s needs to be counted in the data. There are 2 types of parity bit: Even parity bit In the case of even parity, for a given set of bits, the occurrences of bits whose value is 1 are counted. If that count is odd, the parity bit value is set to 1, making the total count of occurrences of 1s in the whole set (including the parity bit) an even number. If the count of 1s in a given set of bits is already even, the parity bit\’s value is 0. Odd parity bit In the case of odd parity, the coding is reversed. For a given set of bits, if the count of bits with a value of 1 is even, the parity bit value is set to 1 making the total count of 1s in the whole set (including the parity bit) an odd number. If the count of bits with a value of 1 is odd, the count is already odd so the parity bit\’s value is 0. Stop bit To stop the transmission, the transmission line goes from low to high voltage for 1-2 bits of the clock pulse. STEPS OF UART TRANSMISSION The data bus of the CPU transmits the bits in parallel form to the transmitter Tx from the controlling devices which can be any of these CPUs of a microprocessor or a microcontroller, memory unit like a RAM or ROM, etc. As UART works asynchronously which means it doesn\’t have a clock signal for synchronizing so now it will use start and stop bits. The transmitter Tx adds these start, stop, and parity bits to the main data and converts its data frame into the serial form. The receiver Rx collects these bits by removing start, stop, and parity bits after checking if there is an error or not. 4.1 If an error is detected, then the receiver will ignore the received byte and request for retransmission of the same byte to the transmitter. 4.2 If not, it will receive it and so on. 5. Then again the receiver Rx converts the serial signal into the parallel form and then the transmitter Tx of the other UART transmits it to the control device via the data bus. Now, how RS232 is connected to UART? RS232 stands for Recommended Standard 232. A standard defining the signals between two devices, defining the signal names, their purpose, voltage levels, connectors, and pinouts. This is a specific interface standard that allows for equipment interoperability. While two pieces of hardware may have UARTs, you don\’t know that they\’ll connect without damage, or communicate properly unless you know they have the same pinout and voltage standards, or include a converter or specially wired cable specific to the interconnection of these two specific devices. To avoid the need for special
Why do we need a rectifier Circuit? Whenever DC power is needed that time, we need to convert an AC Power to DC Power and that process is known as Rectification. A simple PN junction diode acts as a rectifier. The forward biassing and reverse biassing conditions of the diode makes the rectification. Types of Rectifier circuits There are two main types of rectifier circuits, depending upon their output. They are Half-wave Rectifier Full-wave Rectifier A Half-wave rectifier circuit rectifies only positive half cycles of the input supply whereas a Full-wave rectifier circuit rectifies both positive and negative half cycles of the input supply. Half-wave Rectifier Disadvantages of a half-wave rectifier Power is delivered only during the one-half cycle of the input alternating voltage. Ripple factor is high, therefore required to give steady dc output. They only allow a half cycle through per sine wave, and the other half cycle is wasted. This leads to power loss. Full-wave rectifier FWR has two types as follows: Centre tapped full wave rectifier Bridge full-wave Rectifier 1) Centre tapped full wave rectifier Advantages of a center-tapped full-wave rectifier: The ripple factor is much less than that of a half-wave rectifier. DC load current values are twice those of a half-wave rectifier. The rectification efficiency of the full-wave rectifier is double that of a half-wave rectifier. Disadvantages of center-tapped full-wave rectifier Location of center-tapping is difficult. The dc output voltage is small. The PIV of the diodes should be high. 2) Full-wave bridge rectifier Advantages of bridge rectifier: The need for the center-tapped transformer is eliminated. It can be used in application floating output terminals; no output terminal is grounded. The transformer utilization factor, in the case of the bridge rectifier, is higher than that of a center tap rectifier. Disadvantages of Bridge Rectifiers over center tap rectifiers. It requires four diodes for operation, thus, circuit components requirements in the case of the bridge rectifier are more than that of center tap rectifiers. The voltage drop across diodes increases four times that of a center tap full-wave rectifier. Types of Components and Its Symbol used in circuit Schematic of bridge rectifier PCB Layout of bridge rectifier Track Width – 1.00 mm Bill of material During the PCB assembly process, a BOM provides information about the components under a single roof such as their quantity, reference designators, footprints, etc. Designers will save lots of time and effort during PCB design by preparing a bill of materials with all the updated parts list. Every line of the bill of materials (BOM) includes the product code, part name, part number, part revision, description, quantity, unit of measure, size, length, weight, and specifications or features of the product. Go to fabrication bar in Easyeda online tool Download BOM Gerber File Each artwork layer, copper circuitry, power, or ground must have a corresponding Gerber file to create the required pattern. The outermost layers, referenced as “top” and “bottom,” component and solder or by layer count will also have a conforming layer for solder mask and silkscreen to be applied. Summary In this second blog, we have created a schematic of bridge rectifier and pcb layout also and learnt about bill of material and Gerber file. Apart from that we have seen that type of rectifier and understood which one is suitable for industry. Reference https://www.powerelectronicsnews.com/power-supply-design-notes-rectifier-circuits/ https://www.tutorialspoint.com/electronic_circuits/electronic_circuits_full_wave_rectifier.htm https://www.allaboutcircuits.com/textbook/semiconductors/chpt-3/rectifier-circuits/
Static is a keyword in the c/cpp language. It is a storage class specifier that can be applied to any data type. A static keyword can be used with both variables and functions. The static keyword tells the compiler to make the variable or function limited to scope but allows it to persist throughout the life of a program. The static keyword limits the scope of variables or functions to the current source file only. So static keyword helps in hiding the data to one source file only. Static words help in achieving encapsulation in c language. In this blog, we are going to cover the use of static keywords with variables. Static variables are stored in BSS or data segment of the C program Memory Layout. The BSS segment contains the uninitialized data. The DATA segment keeps the initialized data. The static variable is only initialized once, if it is not initialized then it is automatically initialized to 0. void demo(int value) { static int count = 0; count = value; cout<<count; } count = value: is not initialization, it is an assignment. Static can be assigned as many times as we wish. static int count = 0: is initialization & that happens only once for static variables. We can have static global variables or static local variables. Static local variables Static variables are able to retain their value b/w function calls. Static keywords, when used with variables inside the function, are then called static local variables. Static global variables The static keywords when used with variables outside the functions, are then called static global variables. Static global variables help in achieving enumeration, that is they make the scope of the variable limited to the present file only. References: The static keyword in C (c-programming-simple-steps.com)
Here we will understand the basic terms related to microcontrollers.
Introduction to the SPI SPI stands for Serial Peripheral Interface. It is one of the most widely used interfaces between the microcontroller or other peripheral devices such as sensors, shift registers, etc. It uses a Synchronous communication protocol [It shares a clock signal for synchronizing bits between 2 devices] for the communication between a Master[ a microcontroller] and slaves[other peripheral devices]. Usually, a [Master]microcontroller sends a clock signal to the slaves to start the communication between them. SPI uses either 3 or 4 logic signals to communicate SCLK– Shared clock signal [Synchronize data transmission] MOSI– Master Out Slave In [Master sending data to the peripherals] MISO– Master In Slave Out [Master receiving data from the peripherals] CS/SS–Chip/Slave Select [Master indicates that data is being sent] How do SPI works? CS/SS – To start a new transmission the Master pulls the chip select to a low voltage level which means taking the voltage to 0. When it’s done the chip select goes back to its non-transmitting state which is a high voltage level. It is also used for selecting the slave to which master wants to communicate when we have multiple peripherals. When we have multiple slaves they are get connected by the Daisy chain. In Daisy Chain ChipSelect for all the slaves is connected together as in fig below and data propagates from one slave to the next. All the slaves receive the clock signal at the same time. Master sends the data to the first slave and so on. When the data is transferring from one slave to the next, The number of clock cycles required to transmit data is proportional to the slave position. Ex: Assuming we have 2 slaves and we need to transfer the data to the second slave. We have an 8-bit system then we need to send 16 clock pulses[8clockpulses at once as we are taking an 8-bit system] to get to the second slave. But Daisy Chain is not supported by all devices. Reading Data Sheet is recommended for that. SCLK – In SPI the clock signal is generated by the Master. The Master configures the clock, using a frequency supported by the slave device, and sends the clock signal to synchronize the data. Clock Polarity and Clock Phase are the main parameters to define a clock signal which is described later. MOSI/MISO – As SPI is full-duplex, the Master can transmit and receive the data bit by bit at the same time. Master sends the data in series usually MSB goes the first and in MISO, the slave sends the LSB first to the master. Modes of transmission CPOL[clock polarity]- It is used to determine the idle state of the clock. CPHA[clock phase]- Clock Phase determines at which edge data read/write occurs which is described in modes of transmission. If CPOL = 0 , data read/right occurs at falling edge then CPHA=0 If CPOL = 0 , data read/right occurs at rising edge then CPHA=1 If CPOL = 1 , data read/right occurs at rising edge then CPHA=0 If CPOL = 1 , data read/right occurs at falling edge then CPHA=1There are 4 modes of transmission in SPI: Data Transmission Steps The Master selects the chip select line associated with the slave. The Serial Clock line is then enabled. Master starts sending one bit of data on the MOSI line with each clock pulse. Slave reads the MSB first and stores it into memory. MISO line sends the data to the Master. Master reads the LSB first and stores it into the memory. Applications of SPI Memory: SD Card, MMC, EEPROM, Flash. Sensors: Temperature and Pressure. Control Devices: ADC, DAC, digital POTS, and Audio Codec. Others: Camera Lens Mount, touchscreen, LCD, RTC, video game controller, etc
Hello Friends, This is the second blog of the series of PCB designing. Today we are discussing Steps for PCB Designing, Types of Component and methods for mounting components onto a PCB and designing steps. So before discussing the Method for Mounting Components on PCB, first we will discuss the process or different stages of PCB designing. In order to design a PCB, one has to follow below steps : 1. Create the schematic 2. Link footprints to the components in the schematic 3. Generate a netlist 4. Create desired PCB shape in PCB editor 5. Import the netlist in PCB editor 6. Define design rules 7. Place the footprint of the component at desired location 8. Route the tracks to form electrical connections between various components 9. Add labels and identifiers on PCB 10. Generate design file Types of Components and Its Symbol :- So these are some symbols that are used to prepare the schematic. Methods for mounting components onto a PCB. 1. Through Hole: Through-hole components are best used for high-reliability products that require stronger connections between layers. Through-hole component leads run through the board, allowing the components to withstand more environmental stress. This is why through-hole technology is commonly used in military, automobile, and aerospace products that may experience extreme accelerations, collisions, or high temperatures. Through-hole technology is also useful in test and prototyping applications that sometimes require manual adjustment and replacement. 2. SMD (surface-mount devices): SMD components are much smaller than THM components. This will increase the overall density of the board tremendously. Using a Pick and Place machine for placing the components will reduce production time.SMD components are mostly cheaper compared to THM components. surface-mount devices (SMDs) are secured only by solder on the surface of the board SMD components are not suitable for prototyping or testing of small circuits. SMDs cannot be used directly with breadboards SMD solder connections may be damaged by potting compounds going through thermal cycling. EasyEDA Online Tool We will start from EasyEDA, a great web-based EDA(Electronics Design Automation) tool for electronics engineers, educators, students, makers, and enthusiasts. There is no need to install any software. Just open EasyEDA in Browser. EasyEDA Provides: Simple, Easy, Friendly, and Powerful drawing capabilities Works Anywhere, Anytime, on Any Device Real-time Team Cooperation Sharing Online Thousands of open-source projects Integrated PCB fabrication and Components purchase workflow API provided Script support Schematic Capture PCB Layout: Design Rules Checking(DRC) Multi-Layer, 6 copper layer supported Document export(PDF, PNG, SVG) Altium Designer format export BOM export 3D View Generate fabrication file(Gerber) Export Pick and Place file Auto Router Designing Steps Open EasyEDA Tool On Browser Register in EasyEDA Create New Project Draw Schematic Convert that file into BoARD FILE Track the air wire Select needed layers Print the Document Summary In this second blog, we introduced designing steps. Then we discussed the method of mounting components. Introduced the Easyeda Online tool. Reference : https://payatu.com/blog/rupesh/PCB%20Designing%20-%20Basics https://blog.thedigisource.com/through-hole-smt https://www.vishay.com/docs/45242/throughholevssmdcomponents.pdf https://eprpartner.com/through-hole-vs-surface-mounted https://docs.easyeda.com/en/Introduction/Introduction-to-EasyEDA/index.html https://circuitdigest.com/article/design-electronic-circuits-online-with-easyeda
Here we will understand the basic terms related to microcontrollers.
Table of Contents Communication Protocols in Embedded System Serial communication In serial communication, we have only one line for transmitting and receiving data which is why it is half-duplex. It is best for high frequencies as it uses only a single bus or channel for communication, but it can be a bit slower than parallel as it sends only a single bit per clock pulse also because of the single wire here we have fewer chances of cross-talks. It can detect the error as well. When transferring a bit quick change in voltage are required like for 5v OS, 0 bit communicated as a short pulse is 0v, and 1 bit communicated by a short pulse of 5v. In serial communication, the first bit is the most significant bit and the last one is the least significant bit. Parallel Communication In parallel communication, we have a number of lines or buses equal to the number of bits we are transferring. We call it full duplex as the line for transmitting and receiving bits is different. It is faster for small frequencies as all bits are sent at once but as we have to use multiple wires it is costlier also here, we have lots of chances of cross-talks. As in serial, here also we have the first bit is the most significant bit and the last one is the least significant bit. How do they convert? The protocols we have read above communicate in serial form, but they get the data from their peripheral device in parallel form. How do bits get converted into serial form to parallel form? Suppose we have 4 bits, to convert them from parallel to serial we need a Parallel to Serial converter, In the same way, if we want to convert parallel from series, we need a serial to parallel converter. Here comes the D Flip-Flop which is specially designed for such conversions. What is Flip-Flop? A basic memory element or basic digital memory circuit is known as Flip-Flop. It is some medium in which one bit of information (1 or 0) can be stored or retained until it’s necessary. As one flip-flop can store one bit of information. To store multiple bits, we need multiple flip-flops. The group of flip-flops, which are used to store the binary data is known as register. Flip flop circuits are classified into four types based on their use: D-Flip Flop T- Flip Flop SR- Flip Flop JK- Flip Flop. Here for conversion between Serial and parallel bits of data D-Flip Flop is used. Now, what is D Flip-Flop? D flip-flop is also known as Data or Delay Flip-Flop. It has a single D input and a clock input C which is why we call it a D flip-flop. Or for the word delay, it describes what happens to the data at input 0. The data at D input is delayed by one clock pulse before it gets to the output Q. There are two different ways of conversions: Parallel to Serial conversion. First, we need Flip-Flops equivalent to the number of bits. Then we will put the multiplexer in between the Flip-Flop. Multiplexer- It is a combinational circuit that takes input from one of many input lines(parallel) and directs it to a single output line(serial). It has two inputs: 1) From the previous Flip-Flop 2) From Parallel bit data. Now we will load the data which will be transferred one by one.Here msb will be transferred first. Serial to Parallel conversion. First, we need Flip-Flops equivalent to the number of bits. This time we won’t put the multiplexer in between the Flip-Flop. We need to store all the bits at first for this we will pull the clock signal low. Once all bits are loaded, we will pull the clock signal high, and it will shift the LSB to the input of Flip-Flop 1 and output of Flip-Flop 0. Same way all bits gets transferred. Now all the bits are stored in these Flip-Flop and as shown above all the Flip-Flop will transfer the bits at once the way it happens in parallel.. Overview about Serial Communication Protocols in MCU UART Protocol What is UART Protocol? UART stands for Universal Asynchronous Receiver/Transmitter. As we can understand by the name it says it receives and transmits asynchronously. Asynchronously means it doesn’t use clock pulse to synchronize the transmitter and the receiver. In UART, the transmitter takes the signals in parallel from a controlling device[ex-CPU] then it sends the bits to a receiver in serial then the receiver converts those bits in parallel again. UART follows one master one slave approach as it uses only 2 wires for communication. It has one transmitter and one receiver. How does it work? As I, ve mentioned above it transmits asynchronously hence it uses a start and stops a bit, in it contains main data and a parity bit. The parity bit is only needed if the device needs to check the error. When the device wants to start the communication, it pulls the transmitting line low which means it sends a 0 bit and receiving device understands that the transmitter wants to send the data. When the transmission line goes lows it stays low for one clock pulse and then it starts sending the data of 8 bits then the 9th one is a parity bit, the last one is stopping bit it stays high for the one clock pulse until the transmitter sends a low bit to start another frame. To get, in detail understanding on UART Protocol, refer to this blog. SPI Protocol What SPI Protocol is? SPI stands for Serial Peripheral Interface. Just like UART it also uses Serial Communication for transmitting and receiving data but instead of asynchronous it uses synchronous communication protocol for transmission. Synchronous means the transmitter and the receiver must have the same clock signal. It uses a Full duplex communication protocol which means it can send and receive at the same time. SPI
Hello Friends, I’m Taral Mehta. I\’m an Electronics Engineer, This is the first blog of the series to discuss and learn the basics of PCB designing. In this blog, we will discuss, Introduction of PCB and its designing techniques. As well as we will discuss various software that are used for designing the PCB. Table of Contents Starting with Basics of ELectricity Before going to start with PCB designing, we will understand the basic components required: Current – Current is the rate of flow of electric charge. at all points in a series circuit, the current has the same value. If a circuit has a branch, the current flowing into the junction must equal the current flowing out of it. Voltage – Voltage is also known as potential difference.In a circuit loop, the sum of the voltages across the power supplies is always equal to the sum of the voltages across the rest of the components. RESISTOR – Resistance is a measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms CAPACITOR – A capacitor is an electronic component that stores and releases electricity in a circuit. It also passes alternating current without passing direct current. Introduction to PCB (Printed Circuit Board) As an Engineer, whether is Mechanical Engineer, Computer Engineer, or IT Engineer, now and then everybody comes across one of the vital parts of the respective industry i.e. Electronic Circuit. This electronic circuit is made or created on a special type of board, which is called PCB (Printed Circuit Board). As you can see in the above image, PCB has electronic components which are connected through conductive pathways, which are usually called Tracks. A PCB is a thin board made of Fiberglass, composite epoxy or other laminate material. Tracks are etched or printed onto a board, which connects different components on PCB, such as Diode, Resistors, Capacitors and Integrated Circuits (IC). These blue and red lines going criss-cross are the Tracks, which form electrical connections between components. And these Yellow and grey objects are actually footprints or pads of components. I Know that tracks, via and Pads are new parameters for you but don’t worry I will give you a simple answer for your understanding. Traces or Tracks: A trace is a piece of copper, think of a wire, that makes an electrical connection between 2 or more points on a pcb. Traces carry current between these two points on the printed circuit board. You can see an image where RED and BLUE are tracked. Pads: Pads are small areas of copper in predetermined shapes normally used to make a connection to a component pin. Vias: A via is a physical piece of metal that makes electrical connections between layers on the printed circuit board. Vias can carry signals or power between layers using plated through holes. Using this technology a via is formed by drilling a hole through the layers to be connected and then plating the inner surface of the drilled hole. Vias should be sized according to the traces connecting between layers and ultimately how much power it must carry. I think You got a basic idea about what exactly a PCB is… correct? So let’s move further and discuss, What are the designing tools of PCB? PCB Designing Software 1) Eagle 2) OrCAD 3) Proteus 4) KiCad 5) Altium Designer 6) EasyEDA These are some of the famous EDA software presently available in the market. One can use any one of the above lists as per their convenience of use. These are some of the famous EDA software presently available in the market. One can use any one of the above lists as per their convenience of use.EagleorCadProteusKiCadAltium DesignerEasyEDA Previous Next Application: Medical and Healthcare Industry Illumination and Lighting Industry Consumer Electronics Industry Industrial Equipment Industry Aerospace Industry Automotive Industry Safety and Security Equipment Industry Telecommunications Industry Military and Defense Summary To summarize, in this blog first, we did an introduction of PCB. Then we discussed the basics of Electronics. We introduce the Basic Concepts of PCB like Schematic, PCB layers, etc. We discuss some of the PCB designing software and applications currently used in the market. References 1.http://www.pic-control.com/pcb-design-service/ 2.https://qualityinspection.org/electronics-videos-basics-pcb-pcba-smt-process/ 3.https://kitflix.com/how-to-study-pcb-design-getting-started-with-printed-circuit-boards/ 4.https://usa.pcbpower.com/application-and-use-of-pcbs.html 5.https://www.goldphoenixpcb.com/html/Support_Resource/arc_177.html