Jump to content
Electronics-Lab.com Community


  • Content Count

  • Joined

  • Last visited


About Tony_Stoynov

  • Rank
    Advanced Member
  • Birthday 02/07/1977
  1. Hello, You need to control all leds together or you must be able o change each led? The first is easy. Actually you have several possibilities, from custom DC/DC controller to using of standard LED controller you can see this type of controllers from TI Company. You must know that the White led, actually all leds must be controlled via current. You must to have a several current sources for each group of LED's in series. In my application I am using either BD9778 - ROHM DC/DC controller, either TI controllers, this for application that must control all leds together. To build a current source generator you may use any DC/DC controller. Because the DC converter your input voltage can be in wide range. Because the number of leds is big, I can suggest you to use something like a matrix control.
  2. Hi, what exactly you need? About the project, this is a simple and easy to realize. Because you have RS232 I hope you need only two point connection, because multi point with RS232 is a bit difficult. First think is to get a decision what type be a protocol of communication, master/slave or not. When you have a master slave protocol, one master initiate the communication. Another way is any device to initiate a communication. Depending of the application you can use one or another type of communication. Next step is to create a protocol. The core of protocol should be something like this : Byte 1 Start Byte Byte 2 Package length Byte 3 Type of package Byte 4 Command Byte 5 - Byte n data Byte n+1 - CRC 16 Byte n+2 CRC 16 If you have a multipoint communication then is usefully to have a sender address and recipient address. Also depending of data length the CRC can be 8 bit or 32 bit, also you can implement another type of data protection. When you send a data you should use change some of the data. Lets say that you start byte should d be a 0xFF then to prevent false in protocol form data with value 0xFF you should add extra byte. For example your start byte can be 0xFF, 0x00. Each 0xff value n your data you should replace with 0xff,0x01 for example. You will know exactly what is the start byte and what is a data, without chance of mistake. If the protocol is master slave, the master should send some command or data to slave, and slave will return some result, or will execute some command. If the protocol is not master slave, then you must add some extra logic before start a data sending. First you should check the line, if you have a simple RS 232 point to point this not a problem, but if you have a multipoint network communication this is a very important. First you check for the another device transition. Second you start a communication. If you find a data transition you should wait a random number of time and again tray to send a data. Also you should check for the collisions. No matter that the chance is very low, is possible two device to start communication on to same time, no matter the line choking. In that case your should detect a collision, after that you must wait a random time and try again to sent a data. The type of protocol is depending from your communication speed, and application. In critical application I am use master slave communication if have not other requirements. In some case each device should be bale to initiate a communication, in this case a high speed communication is a good solution to solve the problem with a collision and decreasing the real data rate. p.s. excues me if i have a writing errors, i use a spell check in MS word, but i have not time to read careffully the result of speling.
  3. What you need to do, you need radar to determinate the object position and distance to, or just to calculate the distance?
  4. If you still look for company that is able to design this for you pls send me a PM. Below you can find similar product with a 3x3W white led’s
  5. Hi, This chip is MOSFET driver, not a motor driver. The mosfet haven’t the gate current, this 3A impulse is only from the capacitance between gate and Source. What type of motor you will drive?
  6. Hi, This is to same like a laser device. Laser device is better, because the light ray is more coherent, and will be an easier to obtained big distance. The problem their can be the noise, from son, from lamp, from headlight. To reduce this signal you must use a more intelligent sensor. If you use industrial this problem is solve. If you make own, you must use the impulse mode with auto calibration. The bigger problem is if you have two cars with distance small that car length. In this case your sensor will detect front of the first car, and rear of the second. If you want to solve this problem, then the task is a more difficult. One way, but is not very easy is to use optical recognition. Second is to use RFID tags, but this is ....not very accuracy, because depend from the car position, and weather you can have a different distance to tag reading, but if you get starting time and ending time, and give the average between to car time, the error will be a small.
  7. I not sure that you need a model for the processor, and I am not sure that Intel can provide some model. They has internal model, but they is not suitable for the PCB design. Actually you no need from this model. Only one that you need is a good PCB soft, in your case the best decision is a Mentor Graphic. You must simulate only the signal quality and delay. Every chip has a DC and AC signal requirements, when you design your board you must read his requirement, and be under the critical parameters. When you construct the motherboard you will has two big problems. First I a time delay and signal form. This is depending from track length and form. If you has a track with different length and form you can have very big different in time delay. If you’re track ahs a big inductance and capacitance, then the front of the signal will be bad. The second big problem is interference between signal, and EMC compatibility. The Intel a provide simulation model for I/O but actually if you look at chip documentation you can see this models, and use them. This is not easy task. I can suggest before start the design to look at Intel reference design; many of company use directly Intel reference design and make only small correction.
  8. HI, IR optical barier is very suitable. Way you think that F1 timer is expense, in this timer have not nothing special. You can do this very easy. What you ant to create, or how. You want to use standard device, like a sensor, timer etc and just connect them, or you want to make the timer and sensor?
  9. Hi, you can made different construction. The traditional conveir belt is a one or two draving wheels, depend from this one or two direction is movement, and several secondary wheels between them. The belt can be set in motion with friction or with cogwheel. In your case i think you can use cogwheel construction, from old donuts cooking machine, they use a cogwheel and mortiser belt. You can also made a simple construction with two pulley and wire. To drive the DC motor in only one directin you will need relay or transistor. To detect the position yu can use the optobarier sensors.
  10. Hi, presured air, from compresor, via reducer, in compresor tank the presure is around 6 bar, after reducer valve the presure is below 1 bar. But now i think taht temperature of air can be higir that room temperture becouse the compresion, and this may be is a reson for the voaporation.
  11. Hi, look at this topic : http://www.electronics-lab.com/forum/index.php?topic=6246.0
  12. Hi, nobody ..... to get the answer must have a question. Type of the OPAMP, and signal, for example LF411 : Inverting Small signal ~ 200 nS Non Inverting Small signal ~100 ns Inverting Larg signal ~ 1.8 uS Non Inverting Large Signal ~ 1.8 uS Curent Limit Mode ~ 10 uS
  13. Hi, the MP is right, the fericloride is saffety. About the ventilation, i has in the pas thank with aeration, and can say taht aeration increase the voapours.
  14. Hi, the RS485 is very good decision. Afcourse you can use CAN but if you have not a controller with a can module will be a needless work.
  15. Hi, if this is only one way connection, you can use the RS232 with a current loop, or RS422. If you whant a real multi node network, then RS485. If you want something a bit hi-tech you can use a low speed optics, HP has a this type of trancivers, actually this is the agilent, a HP company.
  • Create New...