Archive for the ‘PCB Assembly’ Category

PostHeaderIcon Reverse engineering Microcontroller PIC16F526 Binary

Reverse engineering Microcontroller PIC16F526 Binary

We can Reverse engineering Microcontroller PIC16F526 Binary, please view the Microcontroller PIC16F526 features for your reference:

High-Performance RISC CPU:

· Only 33 Single-Word Instructions

· All Single-Cycle Instructions except for Program Branches which are Two-Cycle when Reverse engineering Microcontroller

· Two-Level Deep Hardware Stack

· Direct, Indirect and Relative Addressing modes for Data and Instructions

· Operating Speed:

– DC – 20 MHz crystal oscillator

– DC – 200 ns instruction cycle

· On-chip Flash Program Memory:

– 1024 x 12 if Reverse engineering Microcontroller

· General Purpose Registers (SRAM):

– 67 x 8

· Flash Data Memory:

– 64 x 8

Special Microcontroller Features:

· 8 MHz Precision Internal Oscillator:

– Factory calibrated to ±1% after Reverse engineering Microcontroller

· In-Circuit Serial Programming™ (ICSP™)

· In-Circuit Debugging (ICD) Support

· Power-On Reset (POR)

· Device Reset Timer (DRT)

· Watchdog Timer (WDT) with Dedicated On-Chip RC Oscillator for Reliable Operation

· Programmable Code Protection

· Multiplexed MCLR Input Pin when Reverse engineering Microcontroller

· Internal Weak Pull-ups on I/O Pins

· Power-Saving Sleep mode

· Wake-Up from Sleep on Pin Change

· Selectable Oscillator Options:

– INTRC: 4 MHz or 8 MHz precision Internal RC oscillator

– EXTRC: External low-cost RC oscillator

– XT:   Standard crystal/resonator

– HS:   High-speed crystal/resonator after Reverse engineering Microcontroller

– LP:   Power-saving, low-frequency crystal

– EC:   High-speed external clock input

Low-Power Features/CMOS Technology:

· Standby current:

– 100 nA @ 2.0V, typical

· Operating current:

– 11 mA @ 32 kHz, 2.0V, typical

– 175 mA @ 4 MHz, 2.0V, typical

· Watchdog Timer current:

– 1 mA @ 2.0V, typical when Reverse engineering Microcontroller

– 7 mA @ 5.0V, typical

· High Endurance Program and Flash Data Memory cells:

– 100,000 write Program Memory endurance

– 1,000,000 write Flash Data Memory endurance

– Program and Flash Data retention: >40 years

· Fully Static Design

· Wide Operating Voltage Range: 2.0V to 5.5V:

– Wide temperature range

– Industrial: -40°C to +85°C

– Extended: -40°C to +125°C before Reverse engineering Microcontroller

Peripheral Features:

· 12 I/O Pins:

– 11 I/O pins with individual direction control

– 1 input-only pin

– High current sink/source for direct LED drive

– Wake-up on change

– Weak pull-ups

· 8-bit Real-time Clock/Counter (TMR0) with 8-bit Programmable Prescaler

· Two Analog Comparators:

– Comparator inputs and output accessible externally

– One comparator with 0.6V fixed on-chip absolute voltage reference (VREF)

– One comparator with programmable on-chip voltage reference (VREF)

· Analog-to-Digital (A/D) Converter:

– 8-bit resolution after Reverse engineering Microcontroller

– 3-channel external programmable inputs

– 1-channel internal input to internal absolute 0.6 voltage reference

PostHeaderIcon Recover Microcontroller PIC16C641 Eeprom

We can Recover Microcontroller PIC16C641 Eeprom, please view the Microcontroller PIC16C641 features for your reference:

High Performance RISC CPU:

· Only 35 instructions to learn

· All single-cycle instructions (200 ns), except for program branches which are two-cycle when Recover Microcontroller

· Operating speed:

DC – 20 MHz clock input

– DC – 200 ns instruction cycle

· Interrupt capability

· 8-level deep hardware stack

· Direct, Indirect and Relative addressing modes

Peripheral Features:

· Up to 33 I/O pins with individual direction control if Recover Microcontroller

· High current sink/source for direct LED drive

· Analog comparator module with:

– Two analog comparators

– Programmable on-chip voltage reference (VREF) module

– Programmable input multiplexing from device inputs and internal voltage reference

– Comparator outputs can be output signals

· Timer0: 8-bit timer/counter with 8-bit programmable prescaler

Special Microcontroller Features:

· Power-on Reset (POR)

· Power-up Timer (PWRT) and Oscillator Start-up Timer (OST)

· Brown-out Reset

· Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation

· Programmable code protection

· Power saving SLEEP mode when MCU RECOVER

· Selectable oscillator options

· Serial in-circuit programming (via two pins)

· Four user programmable ID locations

· Program Memory Parity Error checking circuitry with Parity Error Reset (PER) before Recover Microcontroller

· CMOS Technology:

· Low-power, high-speed CMOS EPROM technology

· Fully static design

· Wide operating voltage range: 3.0V to 6.0V

· Commercial, Industrial and Automotive temperature ranges

· Low power consumption

– < 2.0 mA @ 5.0V, 4.0 MHz

– 15 µA typical @ 3.0V, 32 kHz

– < 1.0 µA typical standby current @ 3.0V

PostHeaderIcon Recover Chip PIC16C554A Eeprom

Recover Chip PIC16C554A Eeprom

We can Recover Chip PIC16C554A Eeprom, please view the Chip PIC16C554A features for your reference:

The PIC16C55X(A) are 18 and 20-Pin EPROM-based members of the versatile PIC16CXX family of low-cost, high-performance,   CMOS,   fully-static,   8-bit microcontrollers.

All PICmicro™ microcontrollers employ an advanced RISC architecture. The PIC16C55X(A) have enhanced core features, eight-level deep stack, and multiple internal and external interrupt sources. The separate instruction and data buses of the Harvard architecture allow a 14-bit wide instruction word with the separate 8-bit wide data if Recover Chip. The two-stage instruction pipeline allows all instructions to execute in a single-cycle, except for program branches (which require two cycles). A total of 35 instructions (reduced instruction set) are available. Additionally, a large register set gives some of the architectural innovations used to achieve a very high performance after Recover Chip.

PIC16C55X(A) microcontrollers typically achieve a 2:1 code compression and a 4:1 speed improvement over other 8-bit microcontrollers in their class.

The PIC16C554(A) and PIC16C556A have 80 bytes of RAM. The PIC16C558(A) has 128 bytes of RAM. Each device has 13 I/O pins and an 8-bit timer/counter with an 8-bit programmable prescaler.

PIC16C55X(A) devices have special features to reduce external components, thus reducing cost, enhancing system reliability and reducing power consumption.

There are four oscillator options, of which the single pin RC oscillator provides a low-cost solution, the LP oscillator minimizes power consumption, XT is a standard crystal, and the HS is for High Speed crystals. The SLEEP (power-down) mode offers power saving.

The user can wake up the chip from SLEEP through several external and internal interrupts and reset.A highly reliable Watchdog Timer with its own on-chip RC oscillator provides protection against software lock- up. A UV-erasable CERDIP-packaged version is ideal for code development while the cost-effective One-Time Programmable (OTP) version is suitable for production in any volume if Recover MCU.

PostHeaderIcon Introduction of Flexible Circuit Assembly

Flexible circuits offer some unique challenges to the assembly process. The assembly materials and processes for populating and interconnecting components to a flexible circuit range are essentially identical to those used for standard rigid or rigid flex pcb, but there are some twists required, as will be shown. The assembly processes range from very simple methods, such as manual component insertion and hand soldering (which requires little or no fixturing), to fully automated methods, which normally require specially developed, design-specific and dedicated fixtures.

How, then, does one choose an assembly process and method for flexible circuits? To begin appropriately, it is necessary to consider a number of important factors: What is the flexible circuit base material? What types of components will be used? How many assemblies will be built? These and other important questions must be addressed before one can adequately make the proper decisions regarding assembly. These seemingly simple matters can greatly influence the pcb assembly choice. For example, it is commonly assumed that polyester circuits cannot be used in applications where soldering is required. The reason for this assumption is that polyester films have a low melt point and will be grossly distorted by the tin-lead soldering process. However, when properly fixtured, soldering can be used for joining components to polyester. A number of major OEMs have been doing just that for many years. They have developed methods that provide proper shielding of the body of the polyester circuit in process. The distortion of the material can be localized to areas adjacent to the point of connection.

With the advent of the well-meant but misguided legislation mandating the use of lead-free solders, there will be significant challenges ahead, as lead-free solders have a roughly 30-40ºC higher melting temperature than traditional tin-lead solders. Sadly, it appears that traditional tin-lead solders are actually more environmentally friendly, so the law does double damage. One alternative is to use lower-temperature solders, or conductive adhesives can also be employed. The important thing is that manufacturers not limit themselves in their thinking and that they be open to alternative solutions. Following is a brief review of the key elements of flex circuit assembly.

PostHeaderIcon Dual probe and Flying probe test

Flying probe doesn’t rely on the pin drawing fixed on fixture. Two or more probes can be installed on the surface of X-Y and move freely, the testing point can be controlled by CAD GERBER FILE. Dual probe can move within 4 mil area. Probe can move isolated, also at the same time didn’t restrict the real distance of how close they can be. Testing device with 2 moving hands is base upon capacitor, press PCB on the insulation layer of a metal sheet as the capacitor for another metal sheet. In case there is 1 wire happen to short, capacitor value will become larger then certain point; if there is a open wire, capacitor will become smaller.

PostHeaderIcon Inspection technology of PCB 1

With the development of surface mount technology, the mounting density of PCB is increasing very fast, as a result of that, even for PCB with less density, automatic inspection is not only basic requirement, but also commercial. During the inspection for complex PCB inspection, 2 normal ways are nail-bed test and flying probe test.

1 Nail-bed test

This kind of way is using probe with spring to connect with each test point on the PCB. Spring can let the probe withstand 100-200gpress force and to ensure each test point working properly, all the nail probe array together can be viewed as nail bed. Under the control of inspection software, we can program test point and test signal, graphic below is a typical structure of nail bed inspection, inspector can acquire all the information about test point. Although both side of PCB can be tested simultaneously by using nail-bed test method, designer should still consider to install all the test point on the solder side of PCB. Nail-bed test device is very expensive and hard to repair.

There is basic universal array processor constitute by drilled bare board, the distance among each pin center is 100mil, 75mil and 50mil. These pins play the role like probe, and use electrical connector or joint on the PCB to make mechanic communication. If PAD on PCB is compatible with test array, then polyamide film which has been drilled orderly can be placed among them for the sake of inspection design. Continual inspection is through get access to end point of network grid. Since all the networks on the PCB can execute continually inspection, then a isolated inspection can be finished. However the distance of each probe constrain the functionality of each nail-bed.

PostHeaderIcon The best way of Printed Circuit Board Welding

1 Wetting

When the hot and liquid soldering tin dissolve and penetrate onto the surface of metal, it can be defined as metal wetting. Molecule of mixture of soldering tin and copper can form a new alloy which contains part of copper and part of soldering tin. Molecule bond is the core of welding, it can decide the hardness and quality of soldering point, wetting can take place only on the copper surface which has not yet being contaminated, no oxide film due to exposure under air, at the same time, temperature should reach certain level.


2 Surface tension

Everyone knows the surface tension on the water, this tension can keep the cold water drop remain the same shape on the metal plate with grease, this is because adhesion which tend to make upper liquid expansion on the surface is smaller than its cohesion. Use warm water and cleanser can reduce the surface tension, water can soak the metal plate with grease and flow out to form a thin film, if the adhesion is bigger than cohesion will occur this situation.

Cohesion of TIN-LEAD soldering tin is even bigger than water, which can make the soldering tin as ball shape which can help to minimize the surface size, to satisfy minimum energy state requirement. Flux play the role as cleanser to metal plate with grease, additional, surface tension is highly depends on the cleaning level and temperature, only adhesion power is much greater than cohesion power, reasonable wetting can occur.


3 Alloy metal

Metallic bond among copper and tin can form grain, the shape and size of grain are determined by soldering temperature and lasting time length, hardness. Less heat during soldering can form more deliberate poikilitic texture, to form the best soldering point with hardest strength. Too much reaction time, either extremely time length of soldering or overheat or both will cause crude poikilitic texture.


PostHeaderIcon What is PCB Soldering?

Soldering is a kind of process through which the metal parts being connected by different kinds of alloy soldering tin. So the parts are capable of connected through surface molecule on the pretext of not being melted.


Soldering include SOFT and HARDEN, temperature of soft soldering below 450℃, temperature of harden soldering above 450℃. Harden Soldering usually be applied on silver, gold, steel and copper, it is soldering point is much more fastness than SOFT soldering, shearing strength is 20-30 times than SOFT soldering, these 2 heat-connecting mentioned above are all using SOLDERING, because the fundamental principle of both soldering methods are all inject the molten soldering tin into the long and narrow aperture of two clean surface of components.


Soldering ensure continuity of metal. First, if two metals connected with each other through bolt connection or physical adhesion, although it can be viewed as a compact integer, but this connection is discontinuous, sometimes if there is an oxidation-insulation film, then they aren’t even physical connection. Another drawback of mechanical connection compare with soldering is if the contact space keep on oxidation will increase the resistance value. Besides, vibration and other mechanical shock will loose the bolt. Soldering can eliminate these problems, soldering locations won’t have relative displacement, contact area won’t oxidize which can help to maintain continue conduction route. Soldering is a process during which 2 metal melted and combine with each other. When soldering tin in the state of molten, it can melt the metal where is being contacted by it, most of the time there could be a very thin oxidation film on the surface of soldering tin covered metal, flux hereby will play the role of melting this oxidation film. Soldering process normally includes:

1> Flux melt down which can help to strip off the oxidation film on the surface of metal;

2> Melt the soldering tin to make the impurity and lighter flux can float onto the surface;

3> Melt partly the metal which has connection with soldering tin;

4> Cold down and finish the fusion process.


PCB Repair need to orient root cause in the circuit board, so usually need to dissemble components from circuit board and do the necessary test and measurement, this process will include:

1> Dissemble special components;

2> Component test;

3> Replace those defected components;

4> Inspect circuit pattern functions;

Dissemble and replace other components will need to instruct soldering procedure.





PostHeaderIcon What is electronic PCB

PCB (Printed Circuit Board): It appears in almost every electronic device. If there exist electronic components a certain kind of equipment, which are set in various sizes of PCB. In addition to fix a variety of small parts, the main function of PCB is to provide electrical connections among the parts. As electronic devices become more complexity which requiring more and more electronic components, the intensity of circuit pattern and electronic parts on the PCB are also increasing simultaneously. Bare board (without any electronic components on it) is also often referred to as “Printed Wiring Board (PWB) “. The substrate of PCB is composed of insulated as well as non-pliable material. Small circuit wire as you can on the surface of laminate is copper foil, copper foil is covered on the surface of raw laminate, and being etched away in the manufacturing process, those part being left behind as a network of fine lines form the circuit pattern. These lines are called conductors (conductor pattern) or said wiring, which are used to provide electrical connections on the PCB for those components.

PostHeaderIcon Several Commonly Used Standards refers to Electronic Manufacture (1)

1> IPC-ESD-2020: United Standard, developed by electrostatic discharge control programme, includes all the necessary design, establishment, installation and maintenance of electrostatic discharge programme. According to the history experience of some military and commercial organization, provide guidance of solution and protection during sensitive period of electrostatic discharge.



2> IPC-AC-62A: Handbook of water clearing after assembly, describe composition of residue and remains, type and feature of cleanser, process of clearing, related equipment and technology, quality control, environment control and employee safety, method of verify the level of clearness and charge of clearing.



3> IPC-DRM-4 9 0E: Evaluation Reference Manual of THROUGH-HOLE soldering point. Describe the components, hole-wall and soldering PAD coverage specification according to the standard in details. Except that, also include the 3D drawing created by computer, include tin filled, contact lead, contact tin, vertical filled and solder PAD cover and lots of soldering points defects.



4> IPC-TA-722: Appraisal Handbook of soldering technology. 45 articles refer to each aspect of soldering technology, content refers to normal soldering, soldering material, manual soldering, soldering in big volume, wave soldering, reflow soldering, vapor phase soldering and infrared soldering.



5> IPC-7525: Template Design Directory. Provide guidelines for design and manufacture of stencil used as template of solder and surface mount bonder, also discuss template design for the application of surface mount technology, introduce hybrid-technology of thru-hole and upside-down chip mounting, include overprint, mackle and stagewise template design.



6> IPC/EIA J-STD-004: Requirement Specification of Flux, include the qualification and category of colophony, resin, Classify organic and Inorganic flux according to the amount of halide and activation level; also include the usage of flux, material which contain flux and no-residue flux when apply in the no-clean process.



7> IPC/EIA J-STD-005: Soldering Paste Specification, list characters of soldering paste and qualification requirement, also include testing method and metal content standard, as well as stickiness, roughness, solder ball, glutinosity, and wetting capability of solder paste.