- 您现在的位置：买卖IC网 > PDF目录79878 > LTC3869IGN-2#TRPBF (LINEAR TECHNOLOGY CORP) SWITCHING CONTROLLER, PDSO28 PDF资料下载
参数资料
| 型号： | LTC3869IGN-2#TRPBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | SWITCHING CONTROLLER, PDSO28 |
| 封装： | 0.150 INCH, LEAD FREE, PLASTIC, SSOP-28 |
| 文件页数： | 6/40页 |
| 文件大小： | 2705K |
| 代理商： | LTC3869IGN-2#TRPBF |
第1页第2页第3页第4页第5页当前第6页第7页第8页第9页第10页第11页第12页第13页第14页第15页第16页第17页第18页第19页第20页第21页第22页第23页第24页第25页第26页第27页第28页第29页第30页第31页第32页第33页第34页第35页第36页第37页第38页第39页第40页
LTC3869/LTC3869-2
14
3869f
For previous generation current mode controllers, the
maximum sense voltage was high enough (e.g., 75mV for
theLTC1628/LTC3728family)thatthevoltagedropacross
the parasitic inductance of the sense resistor represented
a relatively small error. For today’s highest current density
solutions, however, the value of the sense resistor can
be less than 1m and the peak sense voltage can be as
low as 20mV. In addition, inductor ripple currents greater
than 50% with operation up to 1MHz are becoming more
common. Under these conditions the voltage drop across
the sense resistor’s parasitic inductance is no longer neg-
ligible. A typical sensing circuit using a discrete resistor is
shown in Figure 2a. In previous generations of controllers,
a small RC filter placed near the IC was commonly used to
reducetheeffectsofcapacitiveandinductivenoisecoupled
inthe sense traces on the PCB. A typical filter consists of
two series 10 resistors connected to a parallel 1000pF
capacitor, resulting in a time constant of 20ns.
This same RC filter, with minor modifications, can be used
to extract the resistive component of the current sense
signalinthepresenceofparasiticinductance.Forexample,
Figure 3 illustrates the voltage waveform across a 2m
sense resistor with a 2010 footprint for the 1.2V/15A
converter operating at 100% load. The waveform is the
superposition of a purely resistive component and a
purely inductive component. It was measured using two
scope probes and waveform math to obtain a differential
measurement. Based on additional measurements of the
inductor ripple current and the on-time and off-time of
the top switch, the value of the parasitic inductance was
determined to be 0.5nH using the equation:
ESL =
VESL(STEP)
ΔIL
tON tOFF
tON + tOFF
APPLICATIONS INFORMATION
Figure 2. Two Different Methods of Sensing Current
(2a) Using a Resistor to Sense Current
(2b) Using the Inductor DCR to Sense Current
VIN
INTVCC
BOOST
TG
SW
BG
PGND
FILTER COMPONENTS
PLACED NEAR SENSE PINS
SENSE+
SENSE–
SGND
LTC3869
VOUT
3869 F02a
CF 2RF ≤ ESL/RS
POLE-ZERO
CANCELLATION
SENSE RESISTOR
PLUS PARASITIC
INDUCTANCE
RS
ESL
CF
RF
VIN
INTVCC
BOOST
TG
SW
BG
PGND
*PLACE C1 NEAR SENSE+,
SENSE– PINS
**PLACE R1 NEXT TO
INDUCTOR
DCR
L
SENSE+
SENSE–
SGND
LTC3869
VOUT
3869 F02b
R1**
R2
C1*
R1||R2 × C1 =
L
DCR
RSENSE(EQ) = DCR
R2
R1 + R2
相关PDF资料 |
PDF描述 |
|---|---|
| LX1661CDT | 1.5 A SWITCHING CONTROLLER, PDSO16 |
| LS4001-9PV2TB1 | 1-OUTPUT 100 W AC-DC PWR FACTOR CORR MODULE |
| LH3020-2D5 | 3-OUTPUT AC-DC UNREG PWR SUPPLY MODULE |
| LK1001-7ERD6TB1 | 1-OUTPUT 150 W AC-DC REG PWR SUPPLY MODULE |
| LT1029MZ | 1-OUTPUT TWO TERM VOLTAGE REFERENCE, 5 V, PBCY3 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3869IUFD#PBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 标准包装:2,000 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:1MHz 占空比:50% 电源电压:9 V ~ 10 V 降压:无 升压:是 回扫:是 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 85°C 封装/外壳:8-TSSOP（0.173"，4.40mm 宽） 包装:带卷 (TR) |
| LTC3869IUFD#TRPBF | 功能描述:IC REG CTRLR BUCK PWM CM 28-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LTC3872EDDB#PBF | 制造商:Linear Technology 功能描述:DC DC Cntrlr Single-OUT Step Up 2.75V to 9.8V Input 8-Pin DFN EP 制造商:Linear Technology 功能描述:BOOST 2.75 - 9.8V 550KHZ 8D 制造商:Linear Technology 功能描述:BOOST, 2.75 - 9.8V, 550KHZ, 8DFN |
| LTC3872EDDB#TRMPBF | 功能描述:IC REG CTRLR BST PWM CM 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR) |
| LTC3872EDDB#TRPBF | 功能描述:IC REG CTRLR BST PWM CM 8-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR) |
发布紧急采购，3分钟左右您将得到回复。