 |
Electronic Components Datasheet Search |
|
|
Electronic Components Datasheet Search |
|
AL8808 Datasheet(PDF) 16 Page - Diodes Incorporated |
|
|
|||||||||||||||||||||||||||||
AL8808 Datasheet(HTML) 16 Page - Diodes Incorporated |
|
|
16 / 20 page  AL8808 Document number Applicatio EMI and Layo The AL8808 is decoupling and switching speed due to switching The turn-on edg and PCB tracks between the Sch The tracks from short as possible There is an indu estimate the prim and length will d The resonant fre diode. An exam Summary: 1. Use a the gr (EMC 2. Place less th the in parasi more g 3. Place 4. Place 5. Place capac imped r: DS35648 Rev. 2 on Informat out Considerat a switching reg layout of the PC ds of the internal g losses and radia ge (falling edge) . After the Scho hottky diode capa the SW pin to t e. uctance internally mary resonant fr dominate the size equency of any mple of good layo Figure 43. PC PCB constructio round areas are ) operation and a capacitor C1 as han about 5mm. put current pass itic inductance of ground via holes sense resistor R D1 anode, the S capacitor C2 as citor and its copp dance coupling d - 2 tion (cont.) tions ulator with fast CB.To help with power MOSFET ated EMI. dominates the ra ottky diode revers acitance and the the Anode of the y in the AL8808 t equency. If the t e of the inductanc oscillation is det ut is shown in Fi CB Loop Reson on with copper fo tightly connecte also to minimize close as possib To ensure the b ses directly throu f the copper trac s close to the gro R1 as close as po SW pin and the in s close as poss per trace such tha ue to the added w edges and mea these effects the T. The rise and adiated EMI whi se recovery time e track inductanc e Schottky diode this can be assu rack is capable o ce. termined by the gure 44 - the str ance oil on top and bo ed together using device temperat le to VIN, and as best possible EM ugh the capacito ce. Ensure low in ound pad. ossible to VIN and nductor as close ible to L1 and S at the input curre parasitic inducta 16 of 20 www.diodes.co asures small diff e AL8808 has b d fall times are c ch is due to an i of around 5ns h e, LTRACK, See F e, D1, and then f med to be aroun of handling 1A in combined induc ay track inductan ottom. Provide m g plated via hole tures by spreadin close as possib MI filtering (greate r mounting pad. nductance conne d SET. together as poss SET. To ensure ent passes direc ance of the coppe m ferential voltages een developed t controlled to get interaction betwe has occurred; the Figure 43. from D1’s cathod nd 1nH. For PCB ncreasing the thic ctance in the tra nce should be le Figure maximum coverag es placed at reg ng the dissipated le to the cathode est attenuation), This minimizes ection between th sible to avoid rin e the best possib ctly through the c er trace. s; as a result of to minimise radia the right compro een the Schottky e falling edge of de to the decoup B tracks a figure ckness will have ck and the effec ss than 5nH. 44. Recommen ge of copper gro ular intervals. T d heat. e of D1. The sep place the capaci s common imped he capacitor and ging. ble EMI filtering capacitor mountin f this care has ated emissions b omise between p y diode (D1), Sw the SW pin sees pling capacitors of 0.5nH per mm e a minor effect o ctive capacitance nded PCB Layo und plane on bo This is required paration of these itor and its coppe dance coupling d d its ground conn (greatest attenu ng pad. This mi January 201 © Diodes Incorporate AL8808 to be taken with by controlling the power dissipation witching MOSFET s a resonant loop C1 should be as m can be used to on the inductance e of the Schottky ut oth sides. Ensure both for low EM nodes should be er trace such tha due to the added nection. Use 2 o uation), place the nimizes common 3 ed h e n T p s o e y e MI e at d or e n |
|
|
Link URL |
| Does ALLDATASHEET help your business so far? [ DONATE ] |
About Alldatasheet | Advertisement | Contact us | Privacy Policy | Link to Datasheet | Link Exchange | Manufacturer List All Rights Reserved©Alldatasheet.com |
| Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
|
Family Site : ic2ic.com |
icmetro.com |
English ▼
English
Chinese
German
Japanese
Russian
Korean
Spanish
French
Italian
Portuguese
Polish
Vietnamese
Indian
Mexican
British
New Zealand
