参数资料
| 型号： | LTC3813EG#PBF |
| 厂商： | Linear Technology |
| 文件页数： | 15/32页 |
| 文件大小： | 0K |
| 描述： | IC REG CTRLR BST PWM CM 28-SSOP |
| 标准包装： | 47 |
| PWM 型： | 电流模式 |
| 输出数： | 1 |
| 频率 - 最大： | 1MHz |
| 电源电压： | 7 V ~ 75 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 ~ 85°C |
| 封装/外壳： | 28-SSOP（0.209"，5.30mm 宽） |
| 包装： | 管件 |
| 产品目录页面： | 1336 (CN2011-ZH PDF) |
第1页第2页第3页第4页第5页第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页当前第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
LTC3813
APPLICATIONS INFORMATION
increase in coulombs on the horizontal axis from a to b
while the curve is ?at) is speci?ed for a given V DS drain
voltage, but can be adjusted for different V DS voltages by
multiplying by the ratio of the application V DS to the curve
speci?ed V DS values. A way to estimate the C MILLER term
is to take the change in gate charge from points a and b
on a manufacturers data sheet and divide by the stated
V DS voltage speci?ed. C MILLER is the most important se-
lection criteria for determining the transition loss term in
the top MOSFET but is not directly speci?ed on MOSFET
data sheets. C RSS and C OS are speci?ed sometimes but
de?nitions of these parameters are not included.
When the controller is operating in continuous mode
the duty cycles for the top and bottom MOSFETs are
given by:
where ρ T is the temperature dependency of R DS(ON) , R DR
is the effective top driver resistance (approximately 2Ω at
V GS = V MILLER ). V TH(IL) is the data sheet speci?ed typical
gate threshold voltage speci?ed in the power MOSFET data
sheet at the speci?ed drain current. C MILLER is the calculated
capacitance using the gate charge curve from the MOSFET
data sheet and the technique described above.
Both MOSFETs have I 2 R losses while the bottom N-channel
equation includes an additional term for transition losses.
Both top and bottom MOSFET I 2 R losses are greatest at
lowest V IN , and the top MOSFET I 2 R losses also peak
during an overcurrent condition when it is on close to
100% of the period. For most LTC3813 applications,
the transition loss and I 2 R loss terms in the bottom
MOSFET are comparable, so best ef?ciency is obtained
Main Switch Duty Cycle =
V OUT V IN
V OUT
by choosing a MOSFET that optimizes both R DS(ON) and
C MILLER . Since there is no transition loss term in the syn-
chronous MOSFET, however, optimal ef?ciency is obtained
Synchronous Switch Duty Cycle =
V IN
V OUT
by minimizing R DS(ON) —by using larger MOSFETs or
paralleling multiple MOSFETs.
The power dissipation for the main and synchronous
MOSFETs at maximum output current are given by:
Multiple MOSFETs can be used in parallel to lower R DS(ON)
and meet the current and thermal requirements if desired.
The LTC3813 contains large low impedance drivers capable
P MAIN = D MAX
I O(MAX)
1 D MAX
2
(
T )R DS(ON)
of driving large gate capacitances without signi?cantly
slowing transition times. In fact, when driving MOSFETs
with very low gate charge, it is sometimes helpful to
+
1
2
V OUT 2
I O(MAX)
1 D MAX
(R DR )(C MILLER )
slow down the drivers by adding small gate resistors
(10Ω or less) to reduce noise and EMI caused by the
fast transitions.
?
1
DRV CC – V TH(IL)
+
1
V TH(IL)
(f)
P SYNC =
1
1 D MAX
(I O(MAX) ) 2 (
T ) R DS(0N)
3813fb
15
相关PDF资料 |
PDF描述 |
|---|---|
| LTC3814EFE-5#PBF | IC REG CTRLR BST PWM CM 16-TSSOP |
| LTC3816IFE#TRPBF | IC CONTROLLER S-PHASE 38TSSOP |
| LTC3819EG#TRPBF | IC CNTRLR STEP DOWN 36-SSOP |
| LTC3822EGN-1#PBF | IC REG CTRLR BUCK PWM CM 16-SSOP |
| LTC3822EMSE#TRPBF | IC REG CTRLR BUCK PWM CM 10-MSOP |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3813IG#PBF | 功能描述:IC REG CTRLR BST 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:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 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:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX |
| LTC3813IG#TRPBF | 功能描述:IC REG CTRLR BST 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:- 标准包装:4,500 系列:PowerWise® PWM 型:控制器 输出数:1 频率 - 最大:1MHz 占空比:95% 电源电压:2.8 V ~ 5.5 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:-40°C ~ 125°C 封装/外壳:6-WDFN 裸露焊盘 包装:带卷 (TR) 配用:LM1771EVAL-ND - BOARD EVALUATION LM1771 其它名称:LM1771SSDX |
| LTC3814EFE-5#PBF | 功能描述:IC REG CTRLR BST PWM CM 16-TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:- 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 |
| LTC3814EFE-5#TRPBF | 功能描述:IC REG CTRLR BST PWM CM 16-TSSOP 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) |
| LTC3814IFE-5#PBF | 功能描述:IC REG CTRLR BST PWM CM 16-TSSOP 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。