參數(shù)資料
型號(hào): LTC1438CG-ADJ
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(yè)數(shù): 1/32頁(yè)
文件大?。?/td> 596K
代理商: LTC1438CG-ADJ
1
LTC1438/LTC1439
Dual High Efficiency,
Low Noise, Synchronous
Step-Down Switching Regulators
DESCRIPTIO
N
U
Figure 1. High Efficiency Dual 5V/3V Step-Down Converter
I
Maintains Constant Frequency at Low Output Currents
I
Dual N-Channel MOSFET Synchronous Drive
I
Programmable Fixed Frequency (PLL Lockable)
I
Wide V
IN
Range: 3.5V to 36V Operation
I
Ultrahigh Efficiency
I
Very Low Dropout Operation: 99% Duty Cycle
I
Low Dropout, 0.5A Linear Regulator for VPP
Generation or Low Noise Audio Supply
I
Built-In Power-On Reset Timer
I
Programmable Soft Start
I
Low-Battery Detector
I
Remote Output Voltage Sense
I
Foldback Current Limiting (Optional)
I
Pin Selectable Output Voltage
I
Logic-Controlled Micropower Shutdown: I
Q
< 30
μ
A
I
Output Voltages from 1.19V to 9V
I
Available in 28- and 36-Lead SSOP Packages
The LTC
1438/LTC1439 are dual, synchronous step-
down switching regulator controllers which drive external
N-channel power MOSFETs in a phase-lockable fixed
frequency architecture. The Adaptive Power
TM
output stage
selectively drives two N-channel MOSFETs at frequencies
up to 400kHz while reducing switching losses to maintain
high efficiencies at low output currents.
An auxiliary 0.5A linear regulator using an external PNP
pass device provides a low noise, low dropout voltage
source. A secondary winding feedback control pin (SFB1)
guarantees regulation regardless of load on the main
output by forcing continuous operation.
An additional comparator is available for use as a low
battery detector. A power-on reset timer (POR) is included
which generates a signal delayed by 65536/f
CLK
(typ
300ms) after the output is within 5% of the regulated
output voltage. Internal resistive dividers provide pin
selectable output voltages with remote sense capability on
one of the two outputs.
The operating current levels are user-programmable via
external current sense resistors. Wide input supply range
allows operation from 3.5V to 30V (36V maximum).
, LTC and LT are registered trademarks of Linear Technology Corporation.
Adaptive Power is a trademark of Linear Technology Corporation.
FEATURES
TYPICAL APPLICATIO
N
U
BOOST 2
BOOST 1
TGL2
TGS2
SW2
BG2
SENSE
+
2
SENSE
2
V
OSENSE2
I
TH2
TGL1
M3*
M1
M2
TGS1
D1
MBR140T3
V
OUT1
5V
3.5A
V
3.3V
3.5A
L1
10
μ
H
SW1
BG1
LTC1439
SENSE
+
1
SENSE
1
I
TH1
RUN/SS1
C
SS1
0.1
μ
F
C
C1
1000pF
C
OUT1
220
μ
F
10V
R
SENSE1
0.03
R
SENSE2
0.03
C
OUT
220
μ
F
10V
R
C1
10k
RUN/SS2
PGND
SGND
V
PROG2
C
56pF
C
DSC
INTV
CC
D
B2
, CMDSH-3
D
B1
, CMDSH-3
V
IN
V
PROG1
D2
MBR140T3
C
B1
0.1
μ
F
C
B2
,
0.1
μ
F
4.7
μ
F
16V
M6*
1438 F01
M4
1000pF
1000pF
C
SS2
0.1
μ
F
C
220pF
M1, M2, M4, M5: Si4412DY
M3, M6: IRLML2803
*NOT REQUIRED FOR LTC1438
C
470pF
C
1000pF
R
C2
10k
+
L2
10
μ
H
V
5.2V TO 28V
+
+
C
IN
22
μ
F
35V
×
4
+
BOLD LINES INDICATE HIGH CURRENT PATHS
M5
I
Notebook and Palmtop Computers, PDAs
I
Portable Instruments
I
Battery-Operated Devices
I
DC Power Distribution Systems
APPLICATIO
S
U
相關(guān)PDF資料
PDF描述
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相關(guān)代理商/技術(shù)參數(shù)
參數(shù)描述
LTC1438CG-ADJ#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(wú) 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤(pán) 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX
LTC1438CG-ADJ#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(wú) 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤(pán) 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX
LTC1438CG-ADJ#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(wú) 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤(pán) 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX
LTC1438IG 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(wú) 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤(pán) 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX
LTC1438IG#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(wú) 回掃:無(wú) 反相:無(wú) 倍增器:無(wú) 除法器:無(wú) Cuk:無(wú) 隔離:無(wú) 工作溫度:-40°C ~ 125°C 封裝/外殼:6-WDFN 裸露焊盤(pán) 包裝:帶卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名稱:LM1771SSDX