Technical
How to Judge the Acceptance of PCB Quality
Which Color Circuit Board Sells the Most Expensive
Method to Solve the Noise Interference of Power Supply on High-frequency PCB Board
Disassembly Skills of Chip Components on PCB
What Factors Should Be Considered in the Selection of High-frequency PCB CCL
How to Place Special Components during PCB Layout
What Are the Functions of Capacitors in Circuits?
Testing Techniques for Common Electronics Components
What to do if There is a Short Circuit on the PCB
Desoldering Principles and knowhow during PCBA Processing
Black Oxidation of the Inner Layer of the Multilayer PCB
How to Ensure the High-performance Design of PCB
What Is the Printing Process of SMT Solder Paste?
PCB without fiducial mark, Is There Any Way to do SMT for It
What Are the Benefits of Reserving Break-up Tab for PCB Production
How Does SMT Affect PCB Production Time and Speed It Up
Classification of PCBs from three aspects
Common Problems and Solutions for Dry Film pasting during PCB Manufacturing process
Several Elements to Inspect after PCB Design
What is a halogen-free circuit board?
What Do Capacitive Coupling and Decoupling Mean?
What Are the Differences Between PCB Paste Mask and Solder Mask?
How PCBA Is Packaged and Shipped
How long can PCBA finished products be stored?
What Are the Differences and Relations Between PCB, PCBA, and SMT?
PCB Baking Specifications
PCB "Solder Mask Tenting" and "Solder Mask Opening"
Five reasons for PCB deformation and six solutions
Importance of first article inspection of PCBA board
Temperature zone standard for SMT reflow soldering
Small and medium volume PCB manufacturers in China
The main reason for PCBA cleaning
For power filter, the more capacitors, the better?
What does PCBA programming mean?
Content of PCB incoming testing
What conditions must be met for PCB circuit board soldering?
What is Blind via and Buried via
PCBA Manufacturers Temperature and Humidity Sensitive Components Management
Why choose Shenzhen SMT processing factory?
How long does it take to calculate the quotation for PCBA manufacturing?
Introduction of PCB design clearance requirements
Explanation of BOM, DIP, SMT, SMD
Introduction of the process of PCBA prototype
How to prevent pseudo soldering or cold soldering defects in PCBA manufacturing?
Factors that affect the Price of FPCB
What information is required for SMT processing at PCBA factory?
Skills of using 0ohm resistor in PCB design
How to select a PCBA manufacturer
SMT processing solder joint quality inspection
Characteristics difference between immersion gold PCB and gold plating PCB
Common malfunctions of Circuit Board Caused by Moisture
A Few Rules about PCB Panelization
Compare of multi-layer PCB with single/double layer PCB
Why do we need to introduce so many subdivided GND
Difference between immersion gold boards and gold plating boards
Aluminum PCB structure
Classification of different GND in circuit
Why PCB baking is necessary during manufacturing process
The handle and precautions of OSP board in SMT process
How to choose capacitors for filter decoupling
How to choose filter capacitor for switching power supply
5 database need for SMT process
Function of three-terminal capacitor
Introduction of PCB OSP surface treatment
Method of inspecting the quality of SMT by step
How to find the short point between VCC and GND
Difference between 850nm and 940nm infrared LED
Component layout of PCB SMT DFM
Pad shape influence on the strength and reliability of the soldering joints
The difference between high temperature solder paste and low temperature solder paste
Introduction to manual welding processing
Manual visual inspection in PCBA processing
Characteristics of the conformal coating process
Difference between hardware engineers and software engineers
PCBA processing operation rules
China PCB upstream materials has continued to soar
Difference between serial buses and parallel buses
The key points of quality control in PCBA processing
Common causes of solder beading during SMT process
Analysis of the advantages and disadvantages of HASL PCB surface
Requirements for layout of components during SMT assembly
Selection of electronic components and CCL for PCBA
Performance and appearance quality inspection of components.
Quality and Reliability of SMT Chip Processing and Production
Coupling and decoupling function of capacitor
Two methods to connect digital ground and analog ground
Common sense in SMT process

Skills of using 0ohm resistor in PCB design

Zero-ohm resistor is also called a jumper resistor. It is a special-purpose resistor. A 0-ohm resistor does not have a real resistance value of zero. A 0-ohm resistor is actually a resistor with a small resistance value.

In the circuit board design, when two points cannot be connected by circuits. They are often connected by jumpers. This is often seen in ordinary boards. In order to make the automatic placement machine and automatic plug-in machine work normally, zero ohm resistor is used to replace the jumper.

The summary of the functions of zero ohm resistor can include the following:
1. There is no function in the circuit, just for debugging convenience or compatible design on the PCB.

2. Can be used as a jumper to avoid high-frequency interference caused by jumpers (becoming an antenna)

3. When the circuit parameters are uncertain, replace it with 0 ohms. In actual debugging, determine the parameters and replace them with specific components.

4. 0 ohm resistor is actually a resistor with a very small resistor value. When you want to measure the current consumption of a certain part of the circuit, connect a 0 ohm resistor with an ammeter, so that it is convenient to measure the current consumption and can be used to measure large currents.

5. When PCB layout, if it is really not feasible use a line to cross, you can also add a 0 ohm resistor to cross.

6. Under high frequency signals, it acts as an inductor or a capacitor. (Related to external circuit characteristics) Inductance is mainly used to solve EMC problems. Such as between ground and ground, power supply and IC Pin.

7. Single-point grounding (protective grounding, working grounding, and DC grounding are separated from each other on the equipment, and each becomes an independent system.)

8. Configure the circuit, engineers do not want jumpers and DIP switches on products. Sometimes users will change the settings randomly, which is easy to cause error on PCB. In order to reduce maintenance costs, 0 ohm resistors are used instead of jumpers to be soldered on the board.

9. For circuit protection, it acts as a low-cost fuse. Due to the large fusing current of the line on the PCB, it is difficult to fuse if a short-circuit or over-current fault occurs. It may cause bigger accidents.

Since 0 ohm resistor overload current is relatively small (in fact, 0 ohm resistor also has a certain resistor, but it is very small), the 0 ohm resistor is first fused when overcurrent, thereby disconnecting the circuit and preventing greater accidents happened. Sometimes small resistors with a resistor value of a few tenths or a few ohms are used as fuses. However, this is not recommended, but some manufacturers just use it in order to save costs.

In mixed circuits such as digital and analog, the two grounds are often required to be separated and connected at a single point. We can use a 0 ohm resistor to connect the two grounds instead of directly connecting them together. The advantage of this is that the ground wire is divided into two networks, which is much more convenient when add large areas of copper. Incidentally, in such cases, inductors or magnetic beads are sometimes used for connection.


How much current can a zero-ohm resistor withstand? Zero-ohm resistors are often used in circuit design. Generally, the rated power of the resistor is selected according to the current. So which package is the appropriate for 0 ohm?

The actual resistor value of a general 0 ohm resistor is about +-5% deviation, about 50 milliohms. So based on the rated power, you can calculate its rated current.

0402 1/16W: 1/16=I*I*0.05 i.e. I=1.118A;

0603 1/8W: 1/8=I*I*0.05 i.e. I=1.58A;

0805 1/4W: 1/4=I*I*0.05 ie I=2.236A;

For each package, how much current the 0 ohm resistor can pass through is also determined according to the heat dissipation of the resistor on the PCB board.

The relationship between the current and the voltage across the resistor under three packages of 0603, 0805, and 1206 are tested below. It can be seen that the voltage of the three packages begins to rise rapidly after the current actually exceeds 6A.

This shows that the temperature of the resistor has also increased sharply, leading to a significant increase in power consumption. The resistor of 0603 burned when the current increased to 11.5A, the resistor of 0805 burned when the current increased to 12A, and the resistor of 1206 was not burned when the current was 12A.


Current and voltage curve of 0603 package 0 ohm resistance



Current and voltage curve of 0805 package 0 ohm resistance


Current and voltage curve of 1206 package 0 ohm resistance