Printed Circuit Board Assembly Methods

Design-for-manufacturing (DFM) is a well known term and an essential part of the design process. Not as well known but just as important is the concept of design-for-assembly (DFA). If you optimize your circuit board so that it is produced flawlessly, yet make it so the board can only be assembled by tedious hand soldering, then you have saved cents per board on manufacturing just to increase the cost by dollars per board on assembly. To avoid this, both the manufacturing and the assembly need to be taken into account during the design phase. 

Fortunately, there is generally no need to compromise between manufacturing or assembly and in most cases you should be able to design a board that is both highly manufacturable and easily assembled. The first step in being able to design-for-assembly is to understand the assembly process. This process will be discussed in depth to show how a board goes from an unpopulated printed circuit board (PCB) to a final product, ready to be packaged and sent to consumers. You can check the Printed Circuit Board Assembly Methods for more info about this.

Guide of Driving LEDs

The first commercial Light Emitting Diode (LED) was introduced in the 1960’s. From its early beginnings as a low intensity red light, the LED has emerged as a highly versatile component, critical to a wide variety of applications.

Powering LEDs
LEDs are current controlled semiconductor devices. The intensity of the light output is proportional to the current flowing through the junction. Care must be taken to observe the correct polarity of the LED and not to exceed the maximum current rating. In either case, catastrophic damage to the LED may occur. The voltage flowing in the circuit has to be enough to provide the forward drop required by the LED (or LED’s) connected.

Railway DC/DC Converters for Ultra-Wide Input

Just released in the market the most awaited series of the highly efficient DC/DC converters. The new model series was designed due to high demands of variety of applications.

MR1511S series is a family of single output 15 W converters packaged in a compact 1 × 2 inch case is now available from MicroPower Direct.

Five standard models operate from wide 40 VDC to 160 VDC (110 VDC nominal) 4:1 inputs, providing tightly regulated single outputs of 3.3, 5, 12, 15 or 24 VDC. Standard features include line/load regulation less than 1.0%, input/output isolation of 1,500 VDC, a remote control input and efficiency as high as 89%. All models are protected for output short circuit faults and output current faults. The MTBF (per MIL HDBK 217F) is greater than 1.0 Mhours.

Read more about DC/DC converters for ulra-wide input. You can also search about cosel power supply which a very useful info as well.

Switching Power Adaptor for Desktop

One of the switching power adaptors for desktop is so called SPU63-105, which has an output of 75 WATTS of rated power. The good thing about in this adaptor is that it has an input voltage range of 90 – 264 VAC and a frequency range of 47 – 63 Hz.  In addition with this, 88% of efficiency and employs a convection cooling mechanism to facilitate heat dissipation of the system.  You can check to some features of this desktop switching power adapter.

Medical Grade Power Supply

I saw a power supply that was design by medical purposes and that was PMMX300S-12E.  This device is really cool because it features a Power Factor Correction (PFC), which has a power factor of 0.95. This Power Factor Correction (PFC) has capable of delivering 300 W of rated power with a voltage output of 12 V and a current output of 25 Ampere. Safety features of the PMMX300S-12E include over temperature, over current and short circuit protection.

Check the features of Medical Grade Power Supply PMMX300S-12E.

Power Factor Correction

Doing a research about coil to use into my latest coil project. In my circuit design that I would like to create, I would like to use the Power factor correction as my reference which actually I need more research about it because I could not really understand it on how it will be functioning to my circuit diagram. Below are my specs in transformer using the Power factor correction.

• 240V to 120 V at 60 Hz    
• Single-phase 
•  Isolated 
• Low coupling 
• Single primary, dual secondaries

And my expected layouts to choose from are among on these 3 designs.

I was thinking also to use the 018 series, which is a family of passive Power Factor Correction (PFC) coils that includes both in sealed. The 018 series includes a line-up of nine (9) models that have different current rating ranging from 1 – 18 A. If you don’t have any idea about it then see the features of this 018 series for you to check.

• Sealed and open frame
• Laminated core type
• Low audible noise
• Compact and reliable PFC coils
• PVC leads and faston connection
• Specially designed to increase the power factor and reduce THD while maintaining low temperature rise during operation
• Low power losses to extend operational lifetime

FDMF5820DC Smart Power Stage

Have you done creating high current power stage circuit diagram using the FDMF5820DC? Recently, I decided to create one by following the diagram below with instruction of course.  It is the next generation family of Fairchild with fully optimized, ultra-compact, integrated MOSFET plus driver power stage solution for high-current, high frequency, synchronous buck, DC-DC applications.

Check some features of FDMF5820DC.

• Ultra-Compact 5 mm x 5 mm PQFN Copper-Clip Package with Flip Chip Low-Side MOSFET and Dual Cool Architecture

• High Current Handling: 60 A

• 3-State 3.3 V PWM Input Gate Driver

• Dynamic Resistance Mode for Low-Side Drive (LDRV) Slows Low-Side MOSFET during Negative Inductor Current Switching

• Auto DCM (Low-Side Gate Turn Off) Using ZCD# Input

• Thermal Monitor for Module Temperature Reporting

• Programmable Thermal Shutdown (P_THDN)

• HS-Short Detect Fault# / Shutdown

• Dual Mode Enable / Fault# Pin

• Internal Pull-Up and Pull-Down for ZCD# and EN Inputs, respectively

• Fairchild PowerTrench® MOSFETs for Clean Voltage Waveforms and Reduced Ringing

• Fairchild SyncFETTM Technology (Integrated Schottky Diode) in Low-Side MOSFET

• Integrated Bootstrap Schottky Diode