データシートサーチシステム |
|
LM1085IT-ADJ データシート(PDF) 11 Page - Texas Instruments |
|
|
LM1085IT-ADJ データシート(HTML) 11 Page - Texas Instruments |
11 / 22 page LM1085 www.ti.com SNVS038G – JULY 1999 – REVISED MARCH 2013 Figure 21. Heat sink thermal Resistance vs Area THERMAL CONSIDERATION FOR THE DDPAK/TO-263 PACKAGE Unlike the TO-220 package, the TO-263 package uses the printed circuit board as the heat sink to remove heat from the device. The device dissipation is: PD = OUTPUT Section Dissipation + CONTROL Section Dissipation (8) For the LM1085IS-x.x pre-set voltage versions, the dissipation can be calculated using: PD = ( (VIN - VOUT) x ILOAD) + ( (VIN- VOUT) x IGND) (9) The LM1085IS-ADJ adjustable voltage version, the dissipation can be calculated using: PD = ( (VIN - VOUT) x ILOAD) + ( (VIN - VOUT) x (VREF / R1)) (10) Current through the ADJ pin is sufficiently small such that any contribution to the device dissipation is so low that it can safely be ignored. Maximum power dissipation of the LM1085IS depends on the total thermal resistance from the silicon junction through the package TAB ( θJC), into the PC board, copper traces, and other materials, and then into the surrounding air ( θJA), the maximum allowed operating junction temperature (TJ(MAX)) of 125°C, and the maximum ambient temperature (TA(MAX)). The maximum power dissipation in the device is: PD(MAX) = (TJ(MAX) - TA(MAX)) / (θJA (11) For the LM1085IS in the DDPAK/TO-263 3-pin package, the junction-to-case thermal rating, θJC, is 0.7°C/W, where the case is the bottom of the package at the center of the TAB. Typical junction-to-ambient thermal performance for the LM1085IS, using the JESD51 standards, is summarized in the following table: BOARD TYPE THERMAL VIAS θJA JEDEC 2-Layer None 81 °C/W (per JESD 51-3) 0 59 °C/W 2 31 °C/W JEDEC 4-Layer 4 27 °C/W (per JESD 51-7) 8 24 °C/W 12 23 °C/W Copyright © 1999–2013, Texas Instruments Incorporated Submit Documentation Feedback 11 Product Folder Links: LM1085 |
同様の部品番号 - LM1085IT-ADJ |
|
同様の説明 - LM1085IT-ADJ |
|
|
リンク URL |
プライバシーポリシー |
ALLDATASHEET.JP |
ALLDATASHEETはお客様のビジネスに役立ちますか? [ DONATE ] |
Alldatasheetは | 広告 | お問い合わせ | プライバシーポリシー | リンク交換 | メーカーリスト 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 |