参数资料
型号: LTC3839EUH#PBF
厂商: Linear Technology
文件页数: 40/50页
文件大小: 0K
描述: IC REG CTRLR BUCK PWM CM 32-QFN
标准包装: 73
系列: PolyPhase®
PWM 型: 电流模式
输出数: 1
频率 - 最大: 2MHz
电源电压: 4.5 V ~ 38 V
降压:
升压:
回扫:
反相:
倍增器:
除法器:
Cuk:
隔离:
工作温度: -40°C ~ 125°C
封装/外壳: 32-WFQFN 裸露焊盘
包装: 管件
LTC3839
APPLICATIONS INFORMATION
? All power train components should be referenced to
PGND; all components connected to noise-sensitive
pins, e.g., ITH, RT , TRACK/SS and V RNG , should return
to the SGND pin. Keep PGND ample, but SGND area
compact. Use a modified “star ground” technique: a low
impedance, large copper area central PCB point on the
same side of the as the input and output capacitors.
? Place power components, such as C IN , C OUT , MOSFETs,
D B and inductors, in one compact area. Use wide but
shortest possible traces for high current paths (e.g.,
V IN , V OUT , PGND etc.) to this area to minimize copper
loss.
? Keep the switch nodes (SW1,2), top gates (TG1,2) and
boost nodes (BOOST1,2) away from noise-sensitive
small-signal nodes, especially from the opposite chan-
nel’s voltage and current sensing feedback pins. These
nodes have very large and fast moving signals and
therefore should be kept on the “output side” of the
IC (power-related pins are toward the right hand side
of the IC), and occupy minimum PC trace area. Use
compact switch node (SW) planes to improve cooling
of the MOSFETs and to keep EMI down. If DCR sensing
is used, place the top filter resistor (R1 only in Figure 5)
close to the switch node.
? The top N-channel MOSFETs of the two channels have
to be located within a short distance from (preferably
<1cm) each other with a common drain connection at
C IN . Do not attempt to split the input decoupling for the
two channels as it can result in a large resonant loop.
? Connect the input capacitor(s), C IN , close to the power
MOSFETs. This capacitor provides the MOSFET transient
spike current. Connect the drain of the top MOSFET as
close as possible to the (+) plate of the ceramic portion
of input capacitors C IN . Connect the source of the bot-
tom MOSFET as close as possible to the (–) terminal
of the same ceramic C IN capacitor(s). These ceramic
capacitor(s) bypass the high di/dt current locally, and
both top and bottom MOSFET should have short PCB
trace lengths to minimize high frequency EMI and
prevent MOSFET voltage stress from inductive ringing.
? The path formed by the top and bottom N-channel
MOSFETs, and the C IN capacitors should have short
leads and PCB trace. The (–) terminal of output capaci-
tors should be connected close to the (–) terminal of
C IN , but away from the loop described above. This is
to achieve an effect of Kevin (4-wire) connection to the
input ground so that the “chopped” switching current
will not flow through the path between the input ground
and the output ground, and cause common mode output
voltage ripple.
? Several smaller sized ceramic output capacitors, C OUT ,
can be placed close to the sense resistors and before
the rest bulk output capacitors.
? The filter capacitor between the SENSE + and SENSE – pins
should always be as close as possible to these pins.
Ensure accurate current sensing with Kevin (4-wire)
connections to the soldering pads from underneath
the sense resistors or inductor. A pair of sense traces
should be routed together with minimum spacing.
R SENSE , if used, should be connected to the inductor
on the noiseless output side, and its filter resistors
close to the SENSE + /SENSE – pins. For DCR sensing,
however, filter resistor should be placed close to the
inductor, and away from the SENSE + /SENSE – pins, as
its terminal is the SW node.
? Keep small-signal components connected noise-sensi-
tive pins (give priority to SENSE + /SENSE – , V OUTSENSE1+ /
V OUTSENSE1– , RT , ITH, V RNG pins) on the left hand side
of the IC as close to their respective pins as possible.
This minimizes the possibility of noise coupling into
3839fa
40
相关PDF资料
PDF描述
LTC3850IGN-2#TRPBF IC REG CTRLR BUCK PWM CM 28-SSOP
LTC3850IGN#PBF IC REG CTRLR BUCK PWM CM 28-SSOP
LTC3851EGN#PBF IC REG CTRLR BUCK PWM CM 16-SSOP
LTC3851EMSE-1#PBF IC REG CTRLR BUCK PWM CM 16-MSOP
LTC3852EUDD#PBF IC REG CTRLR DOUBLER PWM 24-QFN
相关代理商/技术参数
参数描述
LTC3839IUH#PBF 功能描述:IC REG CTRLR BUCK PWM CM 32-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)
LTC3839IUH#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 32-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)
LTC3850EGN#PBF 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR
LTC3850EGN#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP 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)
LTC3850EGN-1#PBF 功能描述:IC REG CTRLR BUCK PWM CM 28-SSOP 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)