- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377765 > LTC1874EGN (LINEAR TECHNOLOGY CORP) Quadruple 2-Input Positive-AND Gate 14-VQFN -40 to 85 PDF資料下載
參數(shù)資料
| 型號： | LTC1874EGN |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | Quadruple 2-Input Positive-AND Gate 14-VQFN -40 to 85 |
| 中文描述： | 1 A SWITCHING CONTROLLER, 650 kHz SWITCHING FREQ-MAX, PDSO16 |
| 封裝： | 0.150 INCH, PLASTIC, SSOP-16 |
| 文件頁數(shù)： | 9/12頁 |
| 文件大小： | 180K |
| 代理商： | LTC1874EGN |
9
LTC1874
short-circuited. Under this condition the diode must safely
handle I
PEAK
at close to 100% duty cycle. Therefore, it is
important to adequately specify the diode peak current and
average power dissipation so as not to exceed the diode
ratings.
Under normal load conditions, the average current con-
ducted by the diode is:
I
V
V
V
V
I
D
IN
OUT
IN
D
OUT
=
+
The allowable forward voltage drop in the diode is calcu-
lated from the maximum short-circuit current as:
V
P
I
F
D
SC MAX
(
≈
)
where P
D
is the allowable power dissipation and will be
determined by efficiency and/or thermal requirements.
Schottky diodes are a good choice for low forward drop
and fast switching times. Remember to keep lead length
short and observe proper grounding (see Board Layout
Checklist) to avoid ringing and increased dissipation.
C
IN
and C
OUT
Selection
In continuous mode, the source current of the P-channel
MOSFET is a square wave of duty cycle (V
OUT
+ V
D
)/
(V
IN
+ V
D
). To prevent large voltage transients, a low ESR
input capacitor sized for the maximum RMS current must
be used. The maximum RMS capacitor current is given by:
C
I
V
[
V
V
V
IN
MAX
OUT
IN
OUT
IN
Required I
RMS
≈
(
)
]
1 2
This formula has a maximum at V
IN
= 2V
OUT
, where I
RMS
= I
OUT
/2. This simple worst-case condition is commonly
used for design because even significant deviations do not
offer much relief. Several capacitors may be paralleled to
meet the size or height requirements in the design. Due to
the high operating frequency of the controller, ceramic
capacitors can also be used for C
IN
. Always consult the
manufacturer if there is any question.
The selection of C
OUT
is driven by the required effective
series resistance (ESR). Typically, once the ESR require-
ment is satisfied, the capacitance is adequate for filtering.
The output ripple (
V
OUT
) is approximated by:
V
I
ESR
fC
OUT
RIPPLE
OUT
≈
+
1
4
where f is the operating frequency, C
OUT
is the output
capacitance and I
RIPPLE
is the ripple current in the induc-
tor. The output ripple is highest at maximum input voltage
since
I
L
increases with input voltage.
Once the ESR requirement for C
OUT
has been met, the
RMS current rating generally far exceeds the I
RIPPLE(P-P)
requirement. Multiple capacitors may have to be paral-
leled to meet the ESR or RMS current handling require-
ments of the application. Aluminum electrolytic and dry
tantalum capacitors are both available in surface mount
configurations. An excellent choice of tantalum capacitors
are the AVX TPS and KEMET T510 series of surface mount
tantalum capacitors.
APPLICATIOU
W
U
U
相關PDF資料 |
PDF描述 |
|---|---|
| LTC1875 | 15mA Quiescent Current 1.5A Monolithic Synchronous Step-Down Regulator |
| LTC1875EGN | 15mA Quiescent Current 1.5A Monolithic Synchronous Step-Down Regulator |
| LTC1877 | High Efficiency Monolithic Synchronous Step-Down Regulator(高效率,單片同步步降穩(wěn)壓器) |
| LTC1878 | High Efficiency Monolithic Synchronous Step-Down Regulator(高效率,單片同步步降穩(wěn)壓器) |
| LTC1911-15 | Low Noise, High Efficiency, Inductorless Step-Down DC/DC Converter |
相關代理商/技術參數(shù) |
參數(shù)描述 |
|---|---|
| LTC1874EGN#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 16-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 標準包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無 升壓:是 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR) |
| LTC1874EGN#TR | 功能描述:IC REG CTRLR BUCK PWM CM 16-SSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 標準包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無 升壓:是 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR) |
| LTC1874EGN#TRPBF | 功能描述:IC REG CTRLR BUCK PWM CM 16-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:- 標準包裝:2,500 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:500kHz 占空比:96% 電源電壓:4 V ~ 36 V 降壓:無 升壓:是 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 125°C 封裝/外殼:24-WQFN 裸露焊盤 包裝:帶卷 (TR) |
| LTC1875EGN | 功能描述:IC REG BUCK SYNC ADJ 1.5A 16SSOP RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關穩(wěn)壓器 系列:- 標準包裝: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 - 開關:- 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) 供應商設備封裝:10-MSOP 裸露焊盤 |
| LTC1875EGN#PBF | 功能描述:IC REG BUCK SYNC ADJ 1.5A 16SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 開關穩(wěn)壓器 系列:- 標準包裝: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 - 開關: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) 供應商設備封裝:6-SON（1.45x1） 產(chǎn)品目錄頁面:1032 (CN2011-ZH PDF) 其它名稱:296-25628-2 |
發(fā)布緊急采購，3分鐘左右您將得到回復。