- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄30771 > LTC3867IUF#PBF (LINEAR TECHNOLOGY CORP) 0.1 A SWITCHING CONTROLLER, 1200 kHz SWITCHING FREQ-MAX, PQCC24 PDF資料下載
參數(shù)資料
| 型號： | LTC3867IUF#PBF |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | 0.1 A SWITCHING CONTROLLER, 1200 kHz SWITCHING FREQ-MAX, PQCC24 |
| 封裝： | 4 X 4 MM, LEAD FREE, PLASTIC, MO-220WGGD, QFN-24 |
| 文件頁數(shù)： | 17/36頁 |
| 文件大小： | 380K |
| 代理商： | LTC3867IUF#PBF |
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頁當(dāng)前第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頁第28頁第29頁第30頁第31頁第32頁第33頁第34頁第35頁第36頁
LTC3867
24
3867f
APPLICATIONS INFORMATION
SP series of surface mount special polymer capacitors
availableincaseheightsrangingfrom2mmto4mm.Other
capacitor types include Sanyo POSCAP, Sanyo OS-CON,
Nichicon PL series and Sprague 595D series. Consult the
manufacturers for other specific recommendations.
Differential Amplifier
The LTC3867 has true remote voltage sense capability.
The sensing connections should be returned from the
load, back to the differential amplifier’s inputs through a
common, tightly coupled pair of PC traces. The differential
amplifier rejects common mode signals capacitively or
inductively radiated into the feedback PC traces as well
as ground loop disturbances. The LTC3867 diffamp has
high input impedance on DIFF+. It is designed to be used
with a feedback divider Kelvined to the load. The output
of the diffamp connects to the VFB pin.
Nonlinear Control Loop
The LTC3867 features a unique control loop that can speed
up transient response dramatically. This feature is enabled
and programmed through the IFAST pin. When IFAST is
tiedtoINTVCC,thenonlinearcontrolloopisdisabled.VIFAST
is the voltage that can be programmed on the IFAST pin.
There is a precision 10A flowing out of the IFAST pin.
Connecting a resistor to SGND sets the VIFAST voltage.
When VIFAST is set below 1.4V, the difference of 1.4V and
VIFAST sets the threshold voltage that triggers nonlinear
control. Nonlinear control is only enabled when VFB is
within the UV and OV window. It should be enabled only
for forced continuous mode of operation.
Once nonlinear control is enabled, the top gate of all chan-
nels will turn on if:
VFB = VREF –
1.4 – VIFAST
12.5
where VREF is the reference voltage, normally at 0.6V, and
VFB is the feedback voltage.
External Soft-Start and Tracking
The LTC3867 has the ability to either soft-start by itself
or track the output of another channel or external supply.
When the controller is configured to soft-start by itself, a
capacitor may be connected to its TK/SS pin or the internal
soft-start may be used. The controller is in the shutdown
state if its RUN pin voltage is below 1.22V and its TK/SS
pin is actively pulled to ground in this shutdown state. If
the RUN pin voltage is above 1.22V, the controller powers
up. A soft-start current of 1.25A then starts to charge the
TK/SS soft-start capacitor. Note that soft-start or tracking
is achieved not by limiting the maximum output current
of the controller but by controlling the output ramp volt-
age according to the ramp rate on the TK/SS pin. Current
foldback is disabled during this phase to ensure smooth
soft-start or tracking. The soft-start or tracking range is
defined to be the voltage range from 0V to 0.6V on the
TK/SS pin. The total soft-start time can be calculated as:
tSOFTSTART = 0.6
CSS
1.25A
Regardless of the mode selected by the MODE pin, the
controller always starts in discontinuous mode up to
TK/SS = 0.5V. Between TK/SS = 0.5V and 0.565V, it will
operate in forced continuous mode and revert to the
selected mode once TK/SS > 0.565V. The output ripple
is minimized during the 65mV forced continuous mode
window ensuring a clean PGOOD signal. When the chan-
nel is configured to track another supply, the feedback
voltage of the other supply is duplicated by a resistor
divider and applied to the TK/SS pin. Therefore, the volt-
age ramp rate on this pin is determined by the ramp rate
of the other supply’s voltage. It is only possible to track
another supply that is slower than the internal soft-start
ramp. Note that the small soft-start capacitor charging
current is always flowing, producing a small offset error.
To minimize this error, select the tracking resistive divider
value to be small enough to make this error negligible.
In order to track down another channel or supply after
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC4000IUFD#PBF | 1-CHANNEL POWER SUPPLY MANAGEMENT CKT, PQCC28 |
| LTC4000EUFD#PBF | 1-CHANNEL POWER SUPPLY MANAGEMENT CKT, PQCC28 |
| LTC4000EUFD#TRPBF | 1-CHANNEL POWER SUPPLY MANAGEMENT CKT, PQCC28 |
| LTC4000IUFD#TRPBF | 1-CHANNEL POWER SUPPLY MANAGEMENT CKT, PQCC28 |
| LTC4075XEDD | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO10 |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC3868EGN-1#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)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) |
| LTC3868EGN-1#TRPBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)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) |
| LTC3868EUFD-1#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 特色產(chǎn)品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 標(biāo)準(zhǔn)包裝:1 系列:PowerWise® PWM 型:電壓模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:81% 電源電壓:4.5 V ~ 18 V 降壓:是 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-5°C ~ 125°C 封裝/外殼:32-WFQFN 裸露焊盤 包裝:Digi-Reel® 產(chǎn)品目錄頁面:1303 (CN2011-ZH PDF) 其它名稱:LM3754SQDKR |
| LTC3868EUFD-1#TRPBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 標(biāo)準(zhǔn)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) |
| LTC3868EUH#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 32-QFN RoHS:是 類別:集成電路 (IC) >> PMIC - 穩(wěn)壓器 - DC DC 切換控制器 系列:PolyPhase® 特色產(chǎn)品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 標(biāo)準(zhǔn)包裝:1 系列:PowerWise® PWM 型:電壓模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:81% 電源電壓:4.5 V ~ 18 V 降壓:是 升壓:無 回掃:無 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-5°C ~ 125°C 封裝/外殼:32-WFQFN 裸露焊盤 包裝:Digi-Reel® 產(chǎn)品目錄頁面:1303 (CN2011-ZH PDF) 其它名稱:LM3754SQDKR |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。