How to measure the ceramic capacitor

The ceramic capacitors are divided into high frequency porcelain and low frequency ceramic. A capacitor with a small positive temperature coefficient of capacitance for use in a highly stable tank circuit as a loop capacitor and a pad capacitor. Low-frequency ceramic capacitors are limited to bypass or DC-blocking in circuits with lower operating frequencies, or where stability and loss are not critical (including high frequencies). Such capacitors are not suitable for use in pulse circuits because they are susceptible to breakdown by pulse voltages.

According to the dielectric capacitor dielectric, there are two types of dielectric (NP0, C0G), two types of dielectric (X7R, 2X1) and three types of dielectric (Y5V, 2F4) ceramic capacitors. EIA RS-198.

High-voltage ceramic capacitors are circular-plate capacitors made of ceramic materials. In "ceramic" capacitors, DC50v is generally called low voltage, DC100V~500V is medium-high voltage, DC1000v~6000v is high voltage, and safety capacitor Y is also high voltage. Above DC6000v is ultra high pressure.

The high-voltage ceramic capacitor has the characteristics of wear-resistant DC high voltage, and is suitable for high-voltage bypass and coupling circuits. The low-loss high-voltage wafer has low dielectric loss, and is particularly suitable for use in circuits such as television receivers and scanning.

Ceramic capacitor identification:

The identification method of the ceramic capacitor: the identification method of the capacitance is basically the same as the identification method of the resistance, and there are three kinds of methods: the direct label method, the color scale method and the number standard method. The basic unit usage of the capacitor is (F), and other units are: millifarad (mF), microfarad (μF)/mju:/, nanofarad (nF), and picofarad (pF). Where: 1 Farad = 1000 millifarads (mF), 1 millifarad = 1000 microfarads (μF), 1 microfarad = 1000 nanofarads (nF), 1 nanofarad = 1000 picofarads (pF). Capacitance values of large capacity capacitors are directly indicated on the capacitor, such as 10 μF/16V. Capacitance values of capacitors with small capacity are represented by letters or numbers on the capacitors.

Letter notation: 1m=1000 μF 1P2=1.2PF 1n=1000PF

Digital notation: The three-digit representation is also called the digital representation of the capacitance. The first two digits of the three digits are the significant digits of the nominal capacity, and the third digit represents the number of zeros following the significant digit, all of which are in pF.

For example, 102 indicates a nominal capacity of 1000 pF.

221 indicates a nominal capacity of 220 pF.

224 indicates a nominal capacity of 22 x 10 (4) pF.

In this notation, there is a special case where when the third digit is represented by "9", the capacity is multiplied by 10 to the power of -1 to indicate the capacity.

For example, 229 indicates a nominal capacity of 22x (10-1) pF = 2.2 pF.

Allowable error ±1% ±2% ±5% ±10% ±15% ±20%

For example, a ceramic capacitor of 104J indicates a capacity of 0.1 μF and an error of ±5%.

Good or bad detection of ceramic capacitors:

In the process of using various electronic components, once the damage occurs, it will affect the overall operation and performance. Ceramic capacitors are an indispensable key in many electronic products, and their quality determines the operation and life of the equipment. So how do you detect the quality of the ceramic capacitor? Then experts will share a simple test method.

Detect small capacitors below 10pF - Because the fixed capacitor capacity below 10pF is too small, use a multimeter to measure, only qualitatively check for leakage, internal short circuit or breakdown. When measuring, you can use the multimeter R × 10k block, use two meter pens to connect the two pins of the capacitor, the resistance should be infinity. If the measured resistance value (the pointer swings to the right) is zero, the capacitor leakage is damaged or internal breakdown.

Check whether the 10PF~0 01μF fixed capacitor has a charging phenomenon, and then judge whether it is good or bad. The multimeter uses R × 1k block. The beta values of the two triodes are all above 100 and the penetration current is small. A composite tube of 3DG6 and other types of silicon triodes can be selected. The red and black test leads of the multimeter are respectively connected to the emitter e and the collector c of the composite tube. Due to the amplification effect of the composite triode, the charging and discharging process of the measured capacitor is amplified, so that the multimeter pointer swing amplitude is increased, thereby facilitating observation. It should be noted that during the test operation, especially when measuring the capacitance of a small capacity, it is necessary to repeatedly exchange the two points of the measured capacitor pins to contact A and B to clearly see the swing of the multimeter pointer.

For fixed capacitors above 0 01μF, the multimeter's R×10k block can be used to directly test whether the capacitor has a charging process and whether there is an internal short circuit or leakage, and the capacity of the capacitor can be estimated according to the amplitude of the pointer swinging to the right.

Do you know if the quality of the ceramic capacitor is detected? Such a simple detection method can timely check whether the capacitor is faulty or damaged, and timely repair and replace, in order to ensure the production of the product or the operation of the device.

The quality of the ceramic chip capacitor is measured by a multimeter:

The digital multimeter has a capacitance test position, which can directly measure the capacity of the ceramic capacitor. Without this gear position, the capacity cannot be measured, and the resistance file can only be used to roughly judge the continuity.