參數(shù)資料
型號(hào)： LT3688HFE#TRPBF
廠商： LINEAR TECHNOLOGY CORP
元件分類： 穩(wěn)壓器
英文描述： SWITCHING REGULATOR, PDSO24
封裝： LEAD FREE, PLASTIC, TSSOP-24
文件頁(yè)數(shù)： 17/28頁(yè)
文件大?。?/td> 415K
代理商： LT3688HFE#TRPBF
LT3688
24
3688f
Figure 14. Top Layer PCB Layout in the LT3688
Demonstration Board
APPLICATIONS INFORMATION
3688 F14
these components should be as small as possible. These
components, along with the inductor and output capacitor,
should be placed on the same side of the circuit board.
Place a local, unbroken ground plane below these com-
ponents. The SW and BST nodes should be as small as
possible. Finally, keep the FB node small so that the ground
traces will shield them from the SW and BST nodes.
The exposed pad on the bottom of the package must be
soldered to ground so that the pad acts as a heat sink. To
keep thermal resistance low, extend the ground plane as
much as possible, and add thermal vias under and near
the LT3688 to additional ground planes within the circuit
board and on the bottom side.
High Temperature Considerations
The PCB must provide heat sinking to keep the LT3688
cool. The exposed pad on the bottom of the package must
be soldered to a ground plane. This ground should be tied
to large copper layers below with thermal vias; these lay-
ers will spread the heat dissipated by the LT3688. Placing
additional vias can reduce thermal resistance further. With
these steps, the thermal resistance from die (or junction)
to ambient can be reduced to
θJA = 40°C/W or less. With
100 LFPM airow, this resistance can fall by another 25%.
Further increases in airow will lead to lower thermal re-
sistance. Because of the large output current capability of
the LT3688, it is possible to dissipate enough heat to raise
the junction temperature beyond the absolute maximum
of 125°C (150°C for H Grade). When operating at high
ambient temperatures, the maximum load current should
be derated as the ambient temperature approaches 125°C
(150°C for H Grade). Power dissipation within the LT3688
can be estimated by calculating the total power loss from
an efciency measurement and subtracting the catch diode
loss. The die temperature is calculated by multiplying the
LT3688 power dissipation by the thermal resistance from
junction-to-ambient. Thermal resistance depends on the
layout of the circuit board, but values from 30°C/W to
60°C/W are typical. Die temperature rise was measured
on a 4-layer, 5cm 7.5cm circuit board in still air at a load
current of 0.8A (fSW = 800kHz). For a 12V input to 3.3V
output the die temperature elevation above ambient was
14°C; for 12VIN to 5VOUT the rise was 15°C and for 12VIN
to 5VOUT and 3.3VOUT the rise was 30°C.
Other Linear Technology Publications
Application Notes 19, 35 and 44 contain more detailed
descriptions and design information for buck regulators
and other switching regulators. The LT1376 data sheet
has a more extensive discussion of output ripple, loop
compensation and stability testing. Design Note 318
shows how to generate a bipolar output supply using a
buck regulator.
VIN
3688 F13
EN/UVLO
BOOST
SW
LTC3688
BIAS
GND
DA
D4
FB
VIN
VOUT
+
Figure 13. Diode D4 Prevents a Shorted Input from Discharging
a Backup Battery Tied to the Output; It Also Protects the Circuit
from a Reversed Input. The LT3688 Runs Only When the Input
Is Present
相關(guān)PDF資料
PDF描述
LT3689IUD-5#PBF 1.95 A SWITCHING REGULATOR, 2160 kHz SWITCHING FREQ-MAX, PQCC16
LT3689EMSE-5#TRPBF 1.95 A SWITCHING REGULATOR, 2160 kHz SWITCHING FREQ-MAX, PDSO16
LT3689EUD-5#TRPBF 1.95 A SWITCHING REGULATOR, 2160 kHz SWITCHING FREQ-MAX, PQCC16
LT3689EMSE-5#PBF 1.95 A SWITCHING REGULATOR, 2160 kHz SWITCHING FREQ-MAX, PDSO16
LT3689IUD-5#TRPBF 1.95 A SWITCHING REGULATOR, 2160 kHz SWITCHING FREQ-MAX, PQCC16
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LT3688IFE#PBF 功能描述:IC REG BUCK ADJ 0.8A DL 24TSSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 產(chǎn)品培訓(xùn)模塊:MIC23xxx HyperLight Load™ Regulators 標(biāo)準(zhǔn)包裝:5,000 系列:HyperLight Load® 類型:降壓（降壓） 輸出類型:固定 輸出數(shù):1 輸出電壓:1.8V 輸入電壓:2.7 V ~ 5.5 V PWM 型:混合物 頻率 - 開(kāi)關(guān):4MHz 電流 - 輸出:2A 同步整流器:是 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:8-VFDFN 裸露焊盤，8-MLF? 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-MLF?（2x2） 產(chǎn)品目錄頁(yè)面:1094 (CN2011-ZH PDF) 其它名稱:576-3303-2
LT3688IFE#TRPBF 功能描述:IC REG BUCK ADJ 0.8A DL 24TSSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 設(shè)計(jì)資源:Design Support Tool 標(biāo)準(zhǔn)包裝:1 系列:- 類型:升壓（升壓） 輸出類型:固定 輸出數(shù):1 輸出電壓:3V 輸入電壓:0.75 V ~ 2 V PWM 型:- 頻率 - 開(kāi)關(guān):- 電流 - 輸出:100mA 同步整流器:是 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-5 細(xì)型，TSOT-23-5 包裝:剪切帶 (CT) 供應(yīng)商設(shè)備封裝:TSOT-23-5 其它名稱:AS1323-BTTT-30CT
LT3688IFEPBF 制造商:LINER 制造商全稱:Linear Technology 功能描述:Dual 800mA Step-Down Switching Regulator with Power-On Reset
LT3688IUF#PBF 功能描述:IC REG BUCK ADJ 0.8A DL 24QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 產(chǎn)品培訓(xùn)模塊:MIC23xxx HyperLight Load™ Regulators 標(biāo)準(zhǔn)包裝:5,000 系列:HyperLight Load® 類型:降壓（降壓） 輸出類型:固定 輸出數(shù):1 輸出電壓:1.8V 輸入電壓:2.7 V ~ 5.5 V PWM 型:混合物 頻率 - 開(kāi)關(guān):4MHz 電流 - 輸出:2A 同步整流器:是 工作溫度:-40°C ~ 125°C 安裝類型:表面貼裝 封裝/外殼:8-VFDFN 裸露焊盤，8-MLF? 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:8-MLF?（2x2） 產(chǎn)品目錄頁(yè)面:1094 (CN2011-ZH PDF) 其它名稱:576-3303-2
LT3688IUF#TRPBF 功能描述:IC REG BUCK ADJ 0.8A DL 24QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 設(shè)計(jì)資源:Design Support Tool 標(biāo)準(zhǔn)包裝:1 系列:- 類型:升壓（升壓） 輸出類型:固定 輸出數(shù):1 輸出電壓:3V 輸入電壓:0.75 V ~ 2 V PWM 型:- 頻率 - 開(kāi)關(guān):- 電流 - 輸出:100mA 同步整流器:是 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:SOT-23-5 細(xì)型，TSOT-23-5 包裝:剪切帶 (CT) 供應(yīng)商設(shè)備封裝:TSOT-23-5 其它名稱:AS1323-BTTT-30CT
發(fā)布緊急采購(gòu)，3分鐘左右您將得到回復(fù)。

采購(gòu)需求

(若只采購(gòu)一條型號(hào)，填寫一行即可)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

發(fā)布成功！您可以繼續(xù)發(fā)布采購(gòu)。也可以進(jìn)入我的后臺(tái)，查看報(bào)價(jià)

*型號(hào) *數(shù)量 廠商 批號(hào) 封裝
添加更多采購(gòu)

我的聯(lián)系方式

*
*
*