Circuit Design

When I use Multisim Blue mouser version to simulation a circuit. I found that this version do not have a pulse source, so it is difficult to generate a pulse with delay. I found a method that could use pulse by make a component by component wizard. The steps as blew. 1) Select from menu. Tools->Component Wizard Fill the Component name as you like. Select Simulation only. Then click Button “next” Set the number of pins to 2. Then click Button “next” Click Button “copy from DB” Select Clock voltage. Then click Button “OK” Click Button “Next” click Button “Next” Fill Model Name “pulseS” and Fill Model data with: .SUBCKT pulseS CR1 CR2 PARAMS: V1=0 V2=15 TD=0NS TR=10NS TF=10NS PW=20US PER=100US vV1 CR1 CR2 PULSE({V1} {V2} {TD} {TR} {TF} {PW} {PER}) .ENDS Then click Button “Next” Then click Button “Finish”. You can put the component on where you want. When you want to change the parameter, you can right click the components and select “properties”, then click Ta

A digital potentiometer (also called a resistive digital-to-analog converter or informally a digipot ) is a digitally-controlled electronic component that mimics the analog functions of a potentiometer . It is often used for trimming and scaling analog signals by microcontrollers . It Can be divided to Volatile version and Non Volatile version. Volatile Version will reset when lost power. The non-volatile version can keep the set when lost power. Manufacturer Part #: Optional Digital Interface Package Price for 100($) Voltage MCP4024T-103E/OT MCP402X （2.1k, 5k, 10k, 50k） Serial (2-Wire, CS and U/D) SOT-23-5 60 3.3 V, 5 V DS4301U-200+ 200k Up/Down USOP-8 67 2.4 V to 5.5 V MCP4141-103E/MS MCP414X/MCP416X MCP424X/MCP426X Serial (4-Wire, SPI) MSOP-8 61 2.5 V, 3.3 V, 5 V MCP4541-103E/MS MCP454X/MCP456X MCP464X/MCP466X Serial (2-Wire, I2C) MSOP-8 61 2.5 V, 3.3 V, 5 V CAT5140ZI-50-GT3 50k, 100k Serial (

BSS214N H6327 (20V, 1.5A,  106mOhms) (SOT23-3),  Infineon Technologies ,  ($56 for 1000Pcs ) BSS806N H6327 (20V, 2.3A,  41mOhms) (SOT23-3),  Infineon Technologies ,  ($78 for 1000Pcs ) DMG2302UK-7 (20V, 2.8A,  61mOhms) (SOT23-3), Diodes Incorporated ,  ($72 for 1000Pcs ) DMN2041L- 7 (20V, 6.4A,  20mOhms) (SOT23-3),  Diodes Incorporated ,  ($90 for 1000Pcs ) NTR3C21NZT1G (20V, 3.6A,  18mOhms) (SOT23-3), ON Semiconductor ,  ($108 for 1000Pcs ) FDC637BNZ (20V, 6.2A,  24mOhms) (SSOT-6),  ON Semiconductor ,  ($114 for 1000Pcs )

The PCBA manufacture needs a file to tell them where the components should place in SMT machine. You can follow step list below to generate that kinds file in PADS Layout. 1) Set the design units to metric.     Select options in Tools menu.      2) Set the origin to the Bottom Left corner, If there is something is out of the board, you can set the origin to let all object in the board is positive coordinate. Or there may be something wrong when you generate manufacture file use cam. 3) Generate the components place file using CAM PLUS Set as shown in the picture and click Run button. It will generate all the components on the top layer. If you have components on the bottom layer, please run again and change the side to the bottom. The extension name of the generated file is .318. In fact, these files are text files. You can check those file by a text file editor. The file contents are like that.

For 5% resistor (Ohms) 1.0 　　 5.6 　　 33 　　 160 　　 820 　　 3.9K 　　 20K 　　 100K 　　 510K 　　 2.7M 1.1 　　 6.2 　　 36 　　 180 　　 910 　　 4.3K 　　 22K 　　 110K 　　 560K 　　 3M 1.2 　　 6.8 　　 39 　　 200 　　 1K 　　 4.7K 　　 24K 　　 120K 　　 620K 　　 3.3M 1.3 　　 7.5 　　 43 　　 220 　　 1.1K 　　 5.1K 　　 27K 　　 130K 　　 680K 　　 3.6M 1.5 　　 8.2 　　 47 　　 240 　　 1.2K 　　 5.6K 　　 30K 　　 150K 　　 750K 　　 3.9M 1.6 　　 9.1 　　 51 　　 270 　　 1.3K 　　 6.2K 　　 33K 　　 160K 　　 820K 　　 4.3M 1.8 　　 10 　　 56 　　 300 　　 1.5K 　　 6.6K 　　 36K 　　 180K 　　 910K 　　 4.7M 2.0 　　 11 　　 62 　　 330 　　 1.6K 　　 7.5K 　　 39K 　　 200K 　　 1M 　　 5.1M 2.2 　　 12 　　 68 　　 360 　　 1.8K 　　 8.2K 　　 43K 　　 220K 　　 1.1M 　　 5.6M 2.4 　　 13 　　 75 　　 390 　　 2K 　　 9.1K 　　 47K 　　 240K 　　 1.2M 　　 6.2M 2.7 　　 15 　　 82 　　 430 　　 2.2K 　　 10K 　　 51K 　　 270K 　　 1.3M 　　 6.8M 3.0 　　 16 　　 91 　　 470 　　 2.4K 　　 11K 　　 56K 　　 300K 　　 1.5M 　　 7.5M 3.3 　　 18 　　 100 　　 510 　

RZM001P02T2L  (-20V, -100mA, 40Ohms)(SOT-723-3, 1.1mm*1.1mm),  ROHM Semiconductor , ($41 for 1000pcs) RU1C001ZPTL  (-20V, -100mA, 2.5Ohms)( SOT-323FL-3, 1.9mm*2.0mm)  ROHM Semiconductor , ($46 for 1000pcs) RU1C002ZPTCL  (-20V, -200mA, 9.6Ohms,  Vgs-th -300mV ),   ROHM Semiconductor , ($46 for 1000pcs) RSC002P03T316  ()-20V. -250mA, 0.9Ohms ), (SOT-23-3, 2.3mm*2.8mm),  ROHM Semiconductor , ($52 for 1000pcs) BSS84-7-F  (-50V, -130mA, 10Ohms)(SOT-23-3, 2.3mm*2.8mm),  Diodes Incorporated , ($45 for 1000pcs) BSS84P H6327  (-60V, -170mA, 5.8Ohms)(SOT-23-3, 2.3mm*2.8mm),  Diodes Incorporated , ($47 for 1000pcs) DMP210DUFB4-7  (-20V, -200mA, 15Ohms) (X2-DFN1006-3, 0.95mm*0.55mm )  Diodes Incorporated , ($51 for 1000pcs) DMP3099L-7   (-30V, -3.8A, 0.065Ohms ) ((SOT-23-3, 2.3mm*2.8mm)  Diodes Incorporated , ($72 for 1000pcs)

RQ3C150BCTB (-20V, -30A, 4.8mOhms) (HSMT-8)  ROHM Semiconductor ,  ($448 for 1000Pcs ) DMP2008UFG-13 (-20V, -14A, 8mOhms) ( PowerDI3333-8 ),   Diodes Incorporated , ($213 for 1000Pcs ) DMP3017SFG-7 (-30V, -15.2A, 10mOhms)  PowerDI3333-8 ),   Diodes Incorporated , ($171 for 1000Pcs ) DMP3017SFG-13 (-30V, -11.5A, 8.5mOhms) ( PowerDI3333-8 ),   Diodes Incorporated , ($171 for 1000Pcs ) DMG7401SFG-7 (-30V, -9.5A, 9mOhms) ( PowerDI3333-8 ),   Diodes Incorporated , ($213 for 1000Pcs ) SSM6J511NU,LF (-12V, -14A, 6.5mOhms) (UDFN6B-6),  Toshiba , ($148 for 1000Pcs ) MCQ4407-TP (-30V, -12A, 7.8mOhms) (SOP-8),  Micro Commercial Components (MCC) , ($186 for 1000Pcs )

Some times the customer hope the output signal of the sensor should be a current signal. So I design a simple circuit to convert a voltage signal to current signal. Input voltage: 0-5V, output: 4-20mA

I am going to design a circuit that uses a battery as a power source. And an adapter as the input power. So I need a circuit that switches the power source automatically from battery to input power. And I do not want to add a chip to do this because it will increase the cost of the board. The simple circuit for that could be: The shortcoming of this circuit is that it will consume some power by the diode D1 when the adapter plugs in.  In order to overcome this, a P-MOSFET is used to replace it. The simulation showed it works well. I will test it later.

Recently, I am designing a circuit that needs to switch off a module from 12V by a 5V control signal. So I do some research work and make desicion to use the circuit as below. The simulation result as below. The real components in the design list as below. P-Channel MOSFET:  TPH1R712MD (RDSon:1.35mOhms)