- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377776 > LTC3738 (Linear Technology Corporation) 16-Bit Buffer/Driver With 3-State Outputs 48-TSSOP -40 to 85 PDF資料下載
參數(shù)資料
| 型號： | LTC3738 |
| 廠商： | Linear Technology Corporation |
| 英文描述： | 16-Bit Buffer/Driver With 3-State Outputs 48-TSSOP -40 to 85 |
| 中文描述： | 三相降壓控制器與Active定位電壓英特爾VRM9/VRM10 |
| 文件頁數(shù)： | 28/32頁 |
| 文件大?。?/td> | 316K |
| 代理商： | LTC3738 |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁第8頁第9頁第10頁第11頁第12頁第13頁第14頁第15頁第16頁第17頁第18頁第19頁第20頁第21頁第22頁第23頁第24頁第25頁第26頁第27頁當(dāng)前第28頁第29頁第30頁第31頁第32頁
28
LTC3738
3738f
and the worst-case input RMS ripple current for a three
stage design results in peaks at 1/6, 1/2, and 5/6 of the
input voltage. The peaks, however, are at ever decreasing
levels with the addition of more phases. A higher effective
duty factor results because the duty factors “add” as long
as the currents in each stage are balanced. Refer to AN19
for a detailed description of how to calculate RMS current
for the single stage switching regulator.
Figure 5 illustrates the RMS input current drawn from the
input capacitance versus the duty cycle as determined by
the ration of input and output voltage. The peak input RMS
current level of the single phase system is reduced by 2/3
in a 3-phase solution due to the current splitting between
the three stages.
The output ripple current is reduced significantly when
compared to the single phase solution using the same
inductance value because the V
OUT
/L discharge currents
term from the stages that has their bottom MOSFETs on
APPLICATIOU
W
U
U
subtract current from the (V
CC
– V
OUT
)/L charging current
resulting from the stage which has its top MOSFET on. The
output ripple current for a 3-phase design is:
V
f L
I
P-P
=
( )( )(
)
>
DC
V
V
IN
OUT
1 3
–
3
The ripple frequency is also increased by three, further
reducing the required output capacitance when V
CC
< 3V
OUT
as illustrated in Figure 3.
Efficiency Calculation
To estimate efficiency, the DC loss terms include the input
and output capacitor ESR, each MOSFET R
DS(ON)
, induc-
tor resistance R
L
, the sense resistance R
SENSE
and the
forward drop of the Schottky rectifier at the operating
output current and temperature. Typical values for the
design example given previously in this data sheet are:
Main MOSFET R
DS(ON)
= 13.5m
(18m
at 90
°
C)
Sync MOSFET R
DS(ON)
= 4m
(5.3m
at 90
°
C)
C
INESR
= 20m
C
OUTESR
= 3m
R
L
= 2m
R
SENSE
= 3m
V
SCHOTTKY
= 0.8V at 15A (0.7V at 90
°
C)
V
OUT
= 1.3V
V
IN
= 12V
I
MAX
= 45A
δ
= 0.5%
°
C
N = 3
f = 400kHz
The main MOSFET is on for the duty factor V
OUT
/V
IN
and
the synchronous MOSFET is on for the rest of the period
or simply (1 – V
OUT
/V
IN
). Assuming the ripple current is
small, the AC loss in the inductor can be made small if a
good quality inductor is chosen. The average current,
I
OUT
is used to simplify the calaculations. The equation
below is not exact but should provide a good technique
for the comparison of selected components and give a
Figure 11. Single and Polyphase Current Waveforms
SW V
SINGLE PHASE
TRIPLE PHASE
I
CIN
I
COUT
SW1 V
SW2 V
SW3 V
I
L1
I
L2
I
L3
I
CIN
I
COUT
3738 F11
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC3738CUHF | 3-Phase Buck Controller for Intel VRM9/VRM10 with Active Voltage Positioning |
| LTC3770 | Synchronous Controller with Margining, Tracking and PLL |
| LTC3770EG | Synchronous Controller with Margining, Tracking and PLL |
| LTC3770EUH | Synchronous Controller with Margining, Tracking and PLL |
| LTC3776 | 16-Bit Buffer/Driver With 3-State Outputs 48-TVSOP -40 to 85 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC3738CUHF | 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件 |
| LTC3738CUHF#PBF | 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件 |
| LTC3738CUHF#TR | 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:否 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件 |
| LTC3738CUHF#TRPBF | 功能描述:IC CTRLR SW REG 3PH STPDWN 38QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - 專用型 系列:- 標(biāo)準(zhǔn)包裝:43 系列:- 應(yīng)用:控制器，Intel VR11 輸入電壓:5 V ~ 12 V 輸出數(shù):1 輸出電壓:0.5 V ~ 1.6 V 工作溫度:-40°C ~ 85°C 安裝類型:表面貼裝 封裝/外殼:48-VFQFN 裸露焊盤 供應(yīng)商設(shè)備封裝:48-QFN（7x7） 包裝:管件 |
| LTC-3743KG | 制造商:Lite-On Semiconductor Corporation 功能描述: |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。