- 您现在的位置：买卖IC网 > PDF目录13968 > LT3991IMSE-5#PBF (Linear Technology)IC REG BUCK 5V 1.2A 10-MSOP PDF资料下载
参数资料
| 型号： | LT3991IMSE-5#PBF |
| 厂商： | Linear Technology |
| 文件页数： | 15/24页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK 5V 1.2A 10-MSOP |
| 标准包装： | 50 |
| 类型： | 降压（降压） |
| 输出类型： | 固定 |
| 输出数： | 1 |
| 输出电压： | 5V |
| 输入电压： | 4.3 V ~ 55 V |
| PWM 型： | 电流模式，混合 |
| 频率 - 开关： | 200kHz ~ 2MHz |
| 电流 - 输出： | 1.2A |
| 同步整流器： | 无 |
| 工作温度： | -40°C ~ 125°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 10-TFSOP，10-MSOP（0.118"，3.00mm 宽）裸露焊盘 |
| 包装： | 管件 |
| 供应商设备封装： | 10-MSOP 裸露焊盘 |
LT3991/LT3991-3.3/LT3991-5
APPLICATIONS INFORMATION
C3
while using the internal boost diode. For reliable BOOST pin
operation with 2.5V outputs use a good external Schottky
diode (such as the ON Semi MBR0540), and a 1μF boost
capacitor (Figure 3b). For output voltages below 2.5V,
the boost diode can be tied to the input (Figure 3c), or to
another external supply greater than 2.8V. However, the
circuit in Figure 3a is more efficient because the BOOST pin
current comes from a lower voltage source. You must also
be sure that the maximum voltage ratings of the BOOST
and BD pins are not exceeded.
The minimum operating voltage of an LT3991 application
is limited by the minimum input voltage (4.3V) and by
BD
V IN V IN BOOST
LT3991
4.7μF SW V OUT
GND
the maximum duty cycle as outlined in the Input Voltage
Range section. For proper start-up, the minimum input
voltage is also limited by the boost circuit. If the input
voltage is ramped slowly, the boost capacitor may not
be fully charged. Because the boost capacitor is charged
with the energy stored in the inductor, the circuit will rely
on some minimum load current to get the boost circuit
running properly. This minimum load will depend on input
and output voltages, and on the arrangement of the boost
circuit. The minimum load generally goes to zero once the
circuit has started. Figure 4 shows a plot of minimum load
to start and to run as a function of input voltage. In many
cases the discharged output capacitor will present a load
to the switcher, which will allow it to start. The plots show
the worst-case situation where V IN is ramping very slowly.
For lower start-up voltage, the boost diode can be tied to
V IN ; however, this restricts the input range to one-half of
the absolute maximum rating of the BOOST pin.
5.0
4.8
4.6
(3a) For V OUT > 2.8V
4.4
4.2
TO START
V IN
V IN
BD
BOOST
D2
4.0
3.8
3.6
TO RUN
3.0
4.7μF
LT3991
GND
SW
C3
V OUT
3.4 V OUT = 3.3V
T A = 25°C
3.2 L = 10μH
f = 400kHz
10
100
1000
LOAD CURRENT (mA)
6.4
(3b) For 2.5V < V OUT < 2.8V
6.2
6.0
TO START
V IN
V IN
BD
BOOST
5.8
LT3991
C3
5.6
TO RUN
4.7μF
GND
SW
3991 FO3
V OUT
5.4
5.2
5.0
V OUT = 5V
T A = 25°C
L = 10μH
f = 400kHz
10
100
1000
(3c) For V OUT < 2.5V; V IN(MAX) = 27V
LOAD CURRENT (mA)
3991 F04
15
Figure 3. Three Circuits for Generating the Boost Voltage
Figure 4. The Minimum Input Voltage Depends on
Output Voltage, Load Current and Boost Circuit
3991fa
相关PDF资料 |
PDF描述 |
|---|---|
| MAX6307EUK44D3+T | IC SUPERVISOR 4.380V SOT23-5 |
| ABM12DRKF-S13 | CONN EDGECARD EXTEND 24POS .156 |
| MAX6307EUK46D3+T | IC SUPERVISOR 4.630V SOT23-5 |
| 35MS522MEFCTZ6.3X5 | CAP ALUM 22UF 35V 20% RADIAL |
| MAX6306EUK30D3+T | IC SUPERVISOR 3.00V SOT23-5 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3991IMSEPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:55V, 1.2A Step-Down Regulator with 2.8 Quiescent Current |
| LT3991IMSETRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:55V, 1.2A Step-Down Regulator with 2.8 Quiescent Current |
| LT3992 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Monolithic Dual Tracking |
| LT3992EFE#PBF | 功能描述:IC REG BUCK ADJ 3A DL 38-TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 设计资源:Design Support Tool 标准包装:1 系列:- 类型:升压（升压） 输出类型:固定 输出数:1 输出电压:3V 输入电压:0.75 V ~ 2 V PWM 型:- 频率 - 开关:- 电流 - 输出:100mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-5 细型，TSOT-23-5 包装:剪切带 (CT) 供应商设备封装:TSOT-23-5 其它名称:AS1323-BTTT-30CT |
| LT3992EFE#TRPBF | 功能描述:IC REG BUCK ADJ 3A DL 38-TSSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 设计资源:Design Support Tool 标准包装:1 系列:- 类型:升压（升压） 输出类型:固定 输出数:1 输出电压:3V 输入电压:0.75 V ~ 2 V PWM 型:- 频率 - 开关:- 电流 - 输出:100mA 同步整流器:是 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SOT-23-5 细型，TSOT-23-5 包装:剪切带 (CT) 供应商设备封装:TSOT-23-5 其它名称:AS1323-BTTT-30CT |
发布紧急采购，3分钟左右您将得到回复。