參數(shù)資料
型號(hào): LT1776I
廠商: Linear Technology Corporation
元件分類: 基準(zhǔn)電壓源/電流源
英文描述: RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
中文描述: 抗輻射高效,5安培開(kāi)關(guān)穩(wěn)壓器
文件頁(yè)數(shù): 15/20頁(yè)
文件大?。?/td> 147K
代理商: LT1776I
15
LT1776
TYPICAL APPLICATIO
N
S
chosen to be significantly above the SHDN pin input
current to minimize its error contribution, but signifi-
cantly below the typical 3.8mA the LT1776 draws in
lockout mode. Resistor R4 is then chosen to yield this
same 200
μ
A, less 2.5
μ
A, with the desired V
IN
UVLO
voltage minus 1.25V applied across it. (The 2.5
μ
A factor
is an allowance to minimize error due to SHDN pin input
current.)
Behavior is as follows: Normal operation is observed at the
nominal input voltage of 40V. As the input voltage is
decreased to roughly 32V, switching action will stop, V
OUT
will drop to zero, and the LT1776 will draw its V
IN
and V
CC
quiescent currents from the V
IN
supply. At a much lower
input voltage, typically 14V or so at 25
°
C, the voltage on
the SHDN pin will drop to the shutdown threshold, and the
part will draw its shutdown current only from the V
IN
rail.
The resistive divider of R4 and R5 will continue to draw
power from V
IN
. (The user should be aware that while the
SHDN pin lockoutthreshold is relatively accurate includ-
ing temperature effects, the SHDN pin shutdownthresh-
old is more coarse, and exhibits considerably more
temperature drift. Nevertheless the shutdown threshold
will always be well below the lockout threshold.)
Minimum Size Inductor Application
Figure 4a employs power path parts that are capable of
delivering the full rated output capability of the LT1776.
Potential users with low output current requirements may
be interested in substituting a physically smaller and less
costly power inductor. The circuit shown in Figure 6a is
topologically identical to the basic application, but speci-
fies a much smaller inductor. This circuit is capable of
delivering up to 400mA at 5V, or, up to 500mA at 3.3V. The
only disadvantage is that due to the increased resistance
in the inductor, the circuit is no longer capable of with-
standing indefinite short circuits to ground. The LT1776
will still current limit at its nominal I
LIM
value, but this will
overheat the inductor. Momentary short circuits of a few
seconds or less can still be tolerated. Typical efficiency is
shown in Figure 6b.
C1
1776 F05
V
IN
+
C2
+
D1
R1
V
OUT
R2
R3
L1
C3
R4
158k
1%
R5
6.19k
1%
C4
C5
V
IN
V
CC
V
SW
LT1776
FB
V
C
SHDN
SYNC
2
5
4
3
7
8
1
6
GND
Figure 5. User Programmable Undervoltage Lockout
相關(guān)PDF資料
PDF描述
LT1776IS8 SPST, 150mA PC Mount Pushbutton
LT1776 Wide Input Range, High Efficiency, Step-Down Switching Regulator(寬輸入范圍,高效率,5V輸出步降開(kāi)關(guān)穩(wěn)壓器)
LT1777C RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
LT1777IS RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
LT1777CS RADIATION HARDENED HIGH EFFICIENCY, 5 AMP SWITCHING REGULATORS
相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LT1776IN8 功能描述:IC REG BUCK ADJ 0.7A 8DIP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:降壓(降壓) 輸出類型:固定 輸出數(shù):1 輸出電壓:1.2V,1.5V,1.8V,2.5V 輸入電壓:2.7 V ~ 20 V PWM 型:- 頻率 - 開(kāi)關(guān):- 電流 - 輸出:50mA 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:10-TFSOP,10-MSOP(0.118",3.00mm 寬)裸露焊盤 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:10-MSOP 裸露焊盤
LT1776IN8#PBF 功能描述:IC REG BUCK ADJ 0.7A 8DIP 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:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:降壓(降壓) 輸出類型:固定 輸出數(shù):1 輸出電壓:1.2V,1.5V,1.8V,2.5V 輸入電壓:2.7 V ~ 20 V PWM 型:- 頻率 - 開(kāi)關(guān):- 電流 - 輸出:50mA 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:10-TFSOP,10-MSOP(0.118",3.00mm 寬)裸露焊盤 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:10-MSOP 裸露焊盤
LT1776IS8 功能描述:IC REG BUCK ADJ 0.7A 8SOIC RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開(kāi)關(guān)穩(wěn)壓器 系列:- 標(biāo)準(zhǔn)包裝:2,500 系列:- 類型:降壓(降壓) 輸出類型:固定 輸出數(shù):1 輸出電壓:1.2V,1.5V,1.8V,2.5V 輸入電壓:2.7 V ~ 20 V PWM 型:- 頻率 - 開(kāi)關(guān):- 電流 - 輸出:50mA 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:10-TFSOP,10-MSOP(0.118",3.00mm 寬)裸露焊盤 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:10-MSOP 裸露焊盤
LT1776IS8#PBF 功能描述:IC REG BUCK ADJ 0.7A 8SOIC 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:- 標(biāo)準(zhǔn)包裝:250 系列:- 類型:降壓(降壓) 輸出類型:固定 輸出數(shù):1 輸出電壓:1.2V 輸入電壓:2.05 V ~ 6 V PWM 型:電壓模式 頻率 - 開(kāi)關(guān):2MHz 電流 - 輸出:500mA 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:6-UFDFN 包裝:帶卷 (TR) 供應(yīng)商設(shè)備封裝:6-SON(1.45x1) 產(chǎn)品目錄頁(yè)面:1032 (CN2011-ZH PDF) 其它名稱:296-25628-2
LT1776IS8#PBF 制造商:Linear Technology 功能描述:IC STEP-DOWN REGULATOR 8-SOIC