- 您現(xiàn)在的位置：買賣IC網(wǎng) > PDF目錄377747 > LTC1438XCG (LINEAR TECHNOLOGY CORP) Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators PDF資料下載
參數(shù)資料
| 型號： | LTC1438XCG |
| 廠商： | LINEAR TECHNOLOGY CORP |
| 元件分類： | 穩(wěn)壓器 |
| 英文描述： | Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators |
| 中文描述： | 2 A DUAL SWITCHING CONTROLLER, 400 kHz SWITCHING FREQ-MAX, PDSO28 |
| 封裝： | 0.209 INCH, PLASTIC, SSOP-28 |
| 文件頁數(shù)： | 8/32頁 |
| 文件大?。?/td> | 596K |
| 代理商： | LTC1438XCG |
第1頁第2頁第3頁第4頁第5頁第6頁第7頁當(dāng)前第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頁第28頁第29頁第30頁第31頁第32頁
8
LTC1438/LTC1439
PI
FU
CTIO
N
S
U
U
SENSE
+
1, SENSE
+
2:
The (+) Input to Each Current
Comparator. Built-in offsets between SENSE
–
1 and
SENSE
+
1 pins in conjunction with R
SENSE1
set the current
trip threshold (same for second controller).
V
OSENSE1,2
:
Receives the remotely sensed feedback volt-
age either from the output directly or from an external
resistive divider across the output. The V
PROG2
pin deter-
mines which point V
OSENSE2
must connect to. The
V
OSENSE1
pin, only available on the LTC1438-ADJ, re-
quires an external resistive divider to set the output
voltage.
V
PROG1
, V
PROG2
:
Programs Internal Voltage Attenuators
for Output Voltage Sensing. The voltage sensing for thefirst
controller is internally connected to SENSE
–
1 while the
V
OSENSE2
pin allows for remote sensing for the second
controller. For V
PROG1
, V
PROG2
< V
INTVCC
/3, the divider is
set for an output voltage of 3.3V. With V
PROG1
,
V
PROG2
> V
INTVCC
/1.5 the divider is set for an output
voltage of 5V. Leaving
V
PROG2
open (DC) allows the output
voltage of the second controller to be set by an external
resistive divider connected to V
OSENSE2
.
C
OSC
:
External capacitor C
OSC
from this pin to ground sets
the operating frequency.
I
TH1
, I
TH2
: Error Amplifier Compensation Point. Each as-
sociated current comparator threshold increases with this
control voltage.
RUN/SS1, RUN/SS2:
Combination of Soft Start and Run
Control Inputs. A capacitor to ground at each of these pins
sets the ramp time to full current output. The time is
approximately 0.5s/
μ
F. Forcing either of these pins below
1.3V causes the IC to shut down the circuitry required for
that particular controller. Forcing both of these pins below
1.3V causes the device to shut down completely. For
applications which require 5V keep-alive, refer to the
LTC1538-AUX/LTC1539.
TGL1, TGL2:
High Current Gate Drives for Main Top
N-Channel MOSFET. These are the outputs of floating
drivers with a voltage swing equal to INTV
CC
superim-
posed on the switch node voltage SW1 and SW2.
TGS1, TGS2:
Gate Drives for Small Top N-Channel
MOSFET. These are the outputs of floating drivers with a
voltage swing equal to INTV
CC
superimposed on the
switch node voltage SW. Leaving TGS1 or TGS2 open
invokes Burst Mode operation for that controller.
BG1, BG2:
High Current Gate Drive Outputs for Bottom
N-Channel MOSFETs. Voltage swing at these pins is from
ground to INTV
CC
.
SFB1:
Secondary Winding Feedback Input. This input acts
only on the first controller and is normally connected to a
feedback resistive divider from the secondary winding.
Pulling this pin below 1.19V will force continuous syn-
chronous operation for the first controller. This pin should
be tied to: ground to force continuous operation; INTV
CC
in applications that don’t use a secondary winding; and a
resistive divider from the output in applications using a
secondary winding.
POR2:
This output is a drain of an N-channel pull-down.
This pin sinks current when the output voltage of the second
controller drops 7.5% below its regulated voltage and re-
leases 65536 oscillator cycles after the output voltage of the
second controller rises to within –5% value of its regulated
value. The POR2 output is asserted when RUN/SS1 and RUN/
SS2 are both low, independant of the V
OUT2
. This pin is not
functional on the LTC1438X.
LBO:
This output is a drain of an N-channel pull-down. This
pin will sink current when the LBI pin goes below 1.19V.
LBI:
The (+) input of a comparator which can be used as
a low-battery voltage detector. The (–) input is connected
to the 1.19V internal reference.
PLLIN:
External Synchronizing Input to Phase Detector.
This pin is internally terminated to SGND with 50k
. Tie
this pin to SGND in applications which do not use the
phase-locked loop.
PLL LPF:
Output of Phase Detector and Control Input of
Oscillator. Normally a series RC lowpass filter network is
connected from this pin to ground. Tie this pin to SGND in
applications which do not use the phase-locked loop. Can
be driven by a 0V to 2.4V logic signal for a frequency
shifting option.
AUXFB:
Feedback Input to the Auxiliary Regulator/Com-
parator. When used as a linear regulator, this input can
either be connected to an external resistive divider or
directly to the collector of the external PNP pass device for
相關(guān)PDF資料 |
PDF描述 |
|---|---|
| LTC1438 | Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators |
| LTC1438CG | Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators |
| LTC1439 | Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators |
| LTC1439CG | Dual, Micropower, Push-Pull Outputs, LinCMOS(TM) Voltage Comparator 8-PDIP 0 to 70 |
| LTC1439IG | Dual High Efficiency, Low Noise, Synchronous Step-Down Switching Regulators |
相關(guān)代理商/技術(shù)參數(shù) |
參數(shù)描述 |
|---|---|
| LTC1438XCG#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:- 標(biāo)準(zhǔn)包裝:4,500 系列:PowerWise® PWM 型:控制器 輸出數(shù):1 頻率 - 最大:1MHz 占空比:95% 電源電壓:2.8 V ~ 5.5 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:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX |
| LTC1438XCG#TR | 功能描述:IC REG CTRLR BUCK PWM CM 28-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(biāo)準(zhǔn)包裝:4,500 系列:PowerWise® PWM 型:控制器 輸出數(shù):1 頻率 - 最大:1MHz 占空比:95% 電源電壓:2.8 V ~ 5.5 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:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX |
| LTC1438XCG#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:- 標(biāo)準(zhǔn)包裝:4,500 系列:PowerWise® PWM 型:控制器 輸出數(shù):1 頻率 - 最大:1MHz 占空比:95% 電源電壓:2.8 V ~ 5.5 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:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX |
| LTC1439CG | 功能描述:IC REG CTRLR BUCK PWM CM 36-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(biāo)準(zhǔn)包裝:2,000 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:50% 電源電壓:9 V ~ 10 V 降壓:無 升壓:是 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 85°C 封裝/外殼:8-TSSOP（0.173"，4.40mm 寬） 包裝:帶卷 (TR) |
| LTC1439CG#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 36-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(biāo)準(zhǔn)包裝:2,000 系列:- PWM 型:電流模式 輸出數(shù):1 頻率 - 最大:1MHz 占空比:50% 電源電壓:9 V ~ 10 V 降壓:無 升壓:是 回掃:是 反相:無 倍增器:無 除法器:無 Cuk:無 隔離:無 工作溫度:-40°C ~ 85°C 封裝/外殼:8-TSSOP（0.173"，4.40mm 寬） 包裝:帶卷 (TR) |
發(fā)布緊急采購，3分鐘左右您將得到回復(fù)。