- 您现在的位置：买卖IC网 > PDF目录79872 > LT3645IMSE#PBF (LINEAR TECHNOLOGY CORP) 1.25 A SWITCHING REGULATOR, 825 kHz SWITCHING FREQ-MAX, PDSO12 PDF资料下载
参数资料
| 型号： | LT3645IMSE#PBF |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 1.25 A SWITCHING REGULATOR, 825 kHz SWITCHING FREQ-MAX, PDSO12 |
| 封装： | LEAD FREE, PLASTIC, MSOP-12 |
| 文件页数： | 5/24页 |
| 文件大小： | 296K |
| 代理商： | LT3645IMSE#PBF |
LT3645
13
3645f
APPLICATIONS INFORMATION
boost circuit. If the input voltage is ramped slowly, or if
the LT3645 is turned on with the EN/UVLO pin when the
output is already in regulation, then the boost capacitor
might 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 generally
goes to zero once the circuit has started. The worst case
situation is when VIN is ramping very slowly. Figure 4a
shows the minimum input voltage needed to start a 5V
application versus output current. Figure 4b shows the
minimum input voltage needed to start a 3.3V application
versus output current.
Soft-Start
The LT3645 includes a 500μs internal soft-start for the
buck converter and a 500μs soft-start for the LDO regula-
tor. Both soft-starts are reset if the EN/UVLO pin is low, if
VIN drops below 3.4V (undervoltage), if VIN exceeds 36V
(overvoltage), or when the die temperature exceeds 160°C
Figure 4.
(4a) Typical Minimum Input Voltage,
VOUT = 5V
(4b) Typical Minimum Input Voltage,
VOUT = 3.3V
(thermal shutdown). The soft-start for the LDO can also be
reset by pulling the EN2 pin low. The soft-start functions
act to reduce the maximum input current during startup.
Soft-start can not be disabled in the LT3645.
Reversed Input Protection
In some systems, the output will be held high when the
input to the LT3645 is absent. This may occur in bat-
tery charging applications or in battery backup systems
where a battery or some other supply is diode OR’d with
the LT3645’s output. If the VIN pin is allowed to oat and
the EN/UVLO pin is held high (either by a logic signal
or because it is tied to VIN), then the LT3645’s internal
circuitry will draw its quiescent current through its SW
pin. This is ne if the system can tolerate a few mA in this
state. You can reduce this current by grounding the EN/
UVLO pin, then the SW pin current will drop to essentially
zero. However, if the VIN pin is grounded while the output
is held high, then parasitic diodes inside the LT3645 can
OUTPUT CURRENT (mA)
1
5.0
INPUT
VOLTAGE
(V)
5.5
6.5
6.0
7.5
7.0
8.0
10
100
3645 F04a
1000
VIN TO RUN
VIN TO START
OUTPUT CURRENT (mA)
1
3.0
INPUT
VOLTAGE
(V)
4.0
3.5
5.0
4.5
6.0
5.5
6.5
10
100
3645 F04b
1000
VIN TO RUN
VIN TO START
相关PDF资料 |
PDF描述 |
|---|---|
| LS1301-9EPD7T | 1-OUTPUT 100 W AC-DC REG PWR SUPPLY MODULE |
| LS1001-7RD5TB1 | 1-OUTPUT AC-DC REG PWR SUPPLY MODULE |
| LS1301-7RD6TB1 | 1-OUTPUT AC-DC REG PWR SUPPLY MODULE |
| LS2660-7RD8TB1 | 2-OUTPUT AC-DC REG PWR SUPPLY MODULE |
| LK4501-7EPD7TB1 | 1-OUTPUT 150 W AC-DC PWR FACTOR CORR MODULE |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT3645IUD#PBF | 功能描述:IC REG DL BUCK/LINEAR 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LT3645IUD#TRPBF | 功能描述:IC REG DL BUCK/LINEAR 16-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 + 切换式 系列:- 标准包装:2,500 系列:- 拓扑:降压（降压）同步（3），线性（LDO）（2） 功能:任何功能 输出数:5 频率 - 开关:300kHz 电压/电流 - 输出 1:控制器 电压/电流 - 输出 2:控制器 电压/电流 - 输出 3:控制器 带 LED 驱动器:无 带监控器:无 带序列发生器:是 电源电压:5.6 V ~ 24 V 工作温度:-40°C ~ 85°C 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* |
| LT3650 | 制造商:LINER 制造商全称:Linear Technology 功能描述:High Voltage High Current Controller for Battery Charging and Power Management |
| LT3650-4.1 | 制造商:LINER 制造商全称:Linear Technology 功能描述:High Voltage 2 Amp Monolithic Li-Ion Battery Charger |
| LT3650-4.2 | 制造商:LINER 制造商全称:Linear Technology 功能描述:High Voltage 2 Amp Monolithic Li-Ion Battery Charger |
发布紧急采购，3分钟左右您将得到回复。