Technical Note 7 General Introduction Holy Stone The Multilayer Ceramic Chip Capacitors supplied in bulk, cassette or taped & reel package are ideally suitable for thick-film Hybrid circuits and automatic surface mounting on printed circuit boards. MLCC’s are mainly used in electronic circuits for by-pass, filtering and smoothing circuit. ¡ Construction and Physical Dimension L BW Cross Section B W t C1 C2 C3 C4 Solder Metal Barrier External Electrodes Inner Electrodes T A EIA style 0201 L W 0.60±0.03 [.024±.002] 1.00±0.05 [.039±.002] 1.60±0.10 [.063±.004] 2.00±0.20 [.079±.008] 3.20±0.30 [.126±.012] 3.20±0.30 [.126±.012] 4.60±0.30 [.181±.012] 4.60±0.30 [.181±.012] 4.60±0.30 [.181±.012] 5.70±0.40 [.220±.016] 5.70±0.40 [.220±.016] 5.70±0.40 [.220±.016] 5.70±0.40 [.220±.016] 0402 0603 0805 1206 1210 1808 1812 1825 2208 2211 2220 2225 Tmax. BWmin Bmin. 0.33 [.013] 0.55 [.022] 0.90 [.035] 1.45 [.057] 1.80 [.071] 2.60 [.102] 2.20 [.087] 3.00 [.118] 2.60 [.102] 2.20 [.087] 3.00 [.118] 3.00 [.118] 3.00 [.118] 0.10 [.004] 0.15 [.006] 0.15 [.006] 0.20 [.008] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.30 [.012] 0.20 [.008] 0.30 [.012] 0.40 [.016] 0.70 [.028] 1.50 [.059] 1.60 [.063] 2.50 [.098] 2.50 [.098] 2.50 [.098] 3.50 [.137] 3.50 [.137] 3.50 [.137] 3.50 [.137] 0.30±0.03 [.011±.002] 0.50±0.05 [.020±.002] 0.80±0.10 [.031±.004] 1.25±0.25 [.049±.008] 1.60±0.20 [.063±.008] 2.50±0.20 [.098±.008] 2.00±0.20 [.079±.008] 3.20±0.30 [.126±.012] 6.35±0.40 [.250±.016] 2.00±0.20 [.197±.008] 2.80±0.40 [.110±.016] 5.00±0.40 [.197±.016] 6.35±0.40 [.250±.016] A C = ε0 · ε Dimensions(mm) [inches] · N t C : Capacitance ε0 : Dielectric constant in the air ε : Proportional dielectric constant A : Overlap Area t : Dielectric Thickness N : Layers ¡ Nominal Capacitance and Tolerance 1. Standard Combination of Nominal Capacitance and Tolerance Class EIA Tolerance Nominal Capacitor Symbol ESeries Ι Π NPO E-12 ,E-24 Series E-3 K(±10%), M(±20%) E-3,E-6 Series E-6 X7E K(±10%), M(±20%) E-3,E-6 Series E12 X5R K(±10%), M(±20%) E-3,E-6 Series E24 Y5U M(±20%),Z(+80/-20 %) E-3 Series Y5V M(±20%),Z(+80/-20 %) E-3 Series Z5U M(±20%),Z(+80/-20 %) E-3 Series X7R J (±5%),K (±10%) 2. E Series (Standard Number) Application Capacitance 2.2 1.0 1.0 1.5 2.2 4.7 3.3 4.7 6.8 1.0 1.2 1.5 1.8 2.2 2.7 3.3 3.9 4.7 5.6 6.8 8.2 1.0 1.2 1.5 1.8 2.2 2.7 3.3 3.9 4.7 5.6 6.8 8.2 1.1 1.3 1.6 2.0 2.4 3.0 3.6 4.3 5.1 6.2 7.5 9.1 - 109- General Introduction Holy Stone ¡EIA Designations For Class ΙDielectrics Coefficient of capacitance (ppm/ ℃) 0.0 1.0 1.5 2.2 3.3 4.7 7.5 C M P R S T U Ex.: C0G U2J Negative Negative For Class Π Dielectrics Multiplier applicable to column Tolerance of temp. coeff.(ppm/ ℃) -1.0 -10 -100 -1000 -10000 +1 +10 +100 +1000 +10000 30 60 120 250 500 1000 2500 0 1 2 3 4 5 6 7 8 9 G H J K L M N 0±30ppm/ ℃ 750±120ppm/ ℃ Low Temp. Symbol High Temp. Symbol Max. %△C Symbol -55℃ -30℃ +10℃ +45℃ +65℃ +85℃ +105℃ +125℃ +150 ℃ +200 ℃ ±1.0% ±1.2% ±2.2% ±3.3% ±4.7% ±7.5% ±10.0% ±15.0% ±22.0% +22% /-33% +22% /-56% +22% /-82% Ex.: X7R Y5V X Y Z 3 4 5 6 7 8 9 A B C D E F P R S T U V -55 ~ +125 ℃ ±15% -30 ~ +85 ℃ +22%/-82% ¡ Operation Temperature Range Class Ι EIA Symbol NPO Π X7R X7E Dielectric Code Temperature Range(℃) -55℃ ~ +125 ℃ N X -55℃ ~ +125℃ C -55℃ ~ +125℃ Capacitance Change 0±30 ppm/℃ ±15% ±4.7% Reference Temperature 20℃ 20℃ 25℃ X5R B -55℃ ~ +85℃ ±15% 20℃ Y5V Y -30℃ ~ +85℃ +22/-82 % 20℃ Y5U E -30℃ ~ +85℃ +22/-56 % 25℃ Z5U Z +10℃ ~ +85℃ +22/-56 % 25℃ ¡ Dielectric Material – Aging Rate △ C/C( %) 2 Aging Rate NPO: 0 X7R/X5R : 2 ~ 4 % /decade Y5U/Z5U : 4~6% / decate Y5V : 6~10 % /decade Aging Rate 0 NPO -2 -4 -6 After performing De-Aging at 150±5 ℃ for 30 minutes and placement room temperature for 48 hours. X5R/X7R -8 -10 -12 Y5U/Z5U -14 -16 Y5V -18 1 0 (48Hr) 10 100 1000 hour - 110- Precautionary Information Holy Stone ¡ Recommended Board Pattern Improper circuit layout and pad/land size may cause excessive or not enough solder amount on the PC board. Not enough solder may create weak joint, and excessive solder may increase the potential of mechanical or thermal cracks on the ceramic capacitor. Therefore we recommend the land size to be as shown in the following table: 1. Size and recommend land dimensions for reflow soldering Capacitor C Slit Land EIA Code Solder Resistor 0201 0402 0603 0805 1206 1210 1808 1812 1825 2208 2211 2220 2225 E D D B A Chip (mm) L 0.60 1.00 1.60 2.00 3.20 3.20 4.60 4.60 4.60 5.70 5.70 5.70 5.70 W 0.30 0.50 0.80 1.25 1.60 2.50 2.00 3.20 6.35 2.00 2.80 5.00 6.35 Land (mm) A 0.2~0.3 0.3~0.5 0.4~0.6 0.7~0.9 2.2~2.4 2.2~2.4 2.8~3.4 2.8~3.4 2.8~3.4 4.0~4.6 4.0~4.6 4.0~4.6 4.0~4.6 B 0.2~0.4 0.3~0.5 0.6~0.7 0.6~0.8 0.8~0.9 1.0~1.2 1.8~2.0 1.8~2.0 1.8~2.0 2.0~2.2 2.0~2.2 2.0~2.2 2.0~2.2 C 0.2~0.4 0.4~0.6 0.6~0.8 0.8~1.1 1.0~1.4 1.8~2.3 1.5~1.8 2.3~3.0 5.1~5.8 1.5~1.8 2.0~2.6 3.5~4.8 5.1~5.8 D ----1.0~2.0 1.0~2.0 1.0~2.8 1.0~2.8 1.0~4.0 1.0~4.0 1.0~4.0 1.0~4.0 1.0~4.0 E ----3.2~3.7 4.1~4.6 3.6~4.1 4.8~5.3 7.1~8.3 3.6~4.1 4.4~4.9 6.6~7.1 7.1~8.3 2. Mechanical strength varies according to location of chip capacitors on the P.C. board. Design layout of components on the PC board must be such a way to minimize the stress imposed on the components, upon flexure of the boards in depanelization or other processes. e perforation c b slit Component layout close to the edge of the board or the “depanelization line” is not recommended. Susceptibility to stress is in the order of: a>b>c and d>e d a ¡ Mounting 1. Sometimes crack is caused by the impact load due to suction nozzle in pick and place operation. In pick and place operation, if the low dead point is too low, excessive stress is applied to component. This may cause cracks in the ceramic capacitor, therefore it is required to move low dead point of a suction nozzle to the higher level to minimize the board warp age and stress on the components. Nozzle pressure is typically adjusted to 1N to 3N (static load) during the pick and place operation. Excessive Stress Warping of Board Warping of Board Nozzle PCB Crack Example : 0805 & 1206 2. Amount of Adhesive a a b c a 0.2mm min. b 70 ~ 100 μm c Do not touch the solder land c - 111- Support pin Precautionary Information Holy Stone ¡ Handling after chip mounted 1. Proper handling is recommended, since excessive bending and twist of the board, depends on the orientation of the chip on the board, may induce mechanical stress and cause internal crack in the capacitor. Lower potential of crack Higher potential of crack Bending Twist D 2. There is a potential of crack if board is warped due to excessive load by check pin ○ ╳ Support Pin Check pin Check pin 3. Examples of PCB dividing/breaking jigs: The outline of PCB breaking jig is shown below. It is recommended when dividing or breaking PCB that they are held near the jig where no bending will occur, this way there will be no compressive stress applied to the components on the PCB. Do not hold the PCB at a position which is far away from the jig, tensile stress to the components may cause them to crack. PCB V-groove PCB splitting jig No Good Dividing Load Direction PCB V-groove Recommend Dividing Load Direction Load Direction Chip Component Chip Component Load Direction - 112- Precautionary Information Holy Stone ¡Soldering 1. Wave Soldering Most of components are wave soldered with solder at 230 to 250°C. Adequate care must be taken to prevent the potential of thermal cracks on the ceramic capacitors. Refer to the soldering methods below for optimum soldering benefits. Recommend flow soldering temperature Profile Soldering Pre-heating Cooling Temperature (°C) 300 250 230 Soldering Method Change in Temp.(℃) 1206 and Under ΔT ≤100~130℃max. 200 ΔT 120seconds or more 60seconds or more 2 to 3 sec. To optimize the result of soldering, proper preheating is essential: 1) Preheat temperature is too low a. Flux flows to easily b. Possibility of thermal cracks 2) Preheat temperature is too high a. Flux deteriorates even when oxide film is removed b. Causes warping of circuit board c. Loss of reliability of chip and other components Cooling Condition: Natural cooling using air is recommended. If the chips are dipped into a solvent for cleaning, the temperature difference (ΔT ) between the solvent and the chips must be less than 100°C. 2. Reflow Soldering Preheat and gradual increase in temperature to the reflow temperature is recommended to decrease the potential of thermal crack on the components. The recommended heating rate depends on the size of component, however it should not exceed 3°C/Sec. Recommend reflow profile for Lead-Free soldering temperature Profile (MIL-STD-202G #210F) Pre-heating Soldering Cooling 260 °C max./ 10 sec. 260max. Temperature (°C) 217 ΔT Soldering Method Change in Temp.(℃) 1206 and Under ΔT ≤190℃ 1210 and Over ΔT ≤130℃ ※ The cycles of soldering : Twice (Max.) 150°C /60sec. Min. 70 to 90 sec. - 113- Precautionary Information Holy Stone 3. Hand Soldering Sudden temperature change in components, results in a temperature gradient recommended in the following table, and therefore may cause internal thermal cracks in the components. In general a hand soldering method is not recommended unless proper preheating and handling practices have been taken. Care must also be taken not to touch the ceramic body of the capacitor with the tip of solder Iron. 350 Soldering Method Temperature (°C) 250 Change in Temp.(℃) 1206 and Under ΔT ≤150℃ 1210 and Over ΔT ≤130℃ 200 ΔT Within 5 seconds. How to Solder Repair by Solder Iron 1) Selection of the soldering iron tip The required temperature of solder iron for any type of repair depends on the type of the tip, the substrate material, and the solder land size. 2) recommended solder iron condition a.) Preheat the substrate to (60°C to 120°C) on a hot plate. Note that due to the heat loss, the actual setting of the hot plate may have to be higher. (For example 100°C to 150°C) b.) Soldering iron power shall not exceed 30 W. c.) Soldering iron tip diameter shall not exceed 3mm. d.) Temperature of iron tip shall not exceed 350°C of Value,and the process should be finished within 5 seconds. (refer to MIL-STD-202G) e.) Do not touch the ceramic body with the tip of solder iron. Direct contact of the soldering iron tip to ceramic body may cause thermal cracks. f.) After soldering operation, let the products cool down gradually in the room temperature. ¡Storage Store the capacitors where the temperature and relative humidity don’t exceed 40°C and 70%RH. We recommend that the capacitors be used within 6 months from the date of manufacturing. Store the products in the original package and do not open the outer wrapped, polyethylene bag, till just before usage. If it is open, seal it as soon as possible or keep it in a desiccant with a desiccation agent. - 114-