- 您现在的位置：买卖IC网 > PDF目录44983 > LT1961IMS8E#TR (LINEAR TECHNOLOGY CORP) 3 A SWITCHING REGULATOR, 1500 kHz SWITCHING FREQ-MAX, PDSO8 PDF资料下载
参数资料
| 型号： | LT1961IMS8E#TR |
| 厂商： | LINEAR TECHNOLOGY CORP |
| 元件分类： | 稳压器 |
| 英文描述： | 3 A SWITCHING REGULATOR, 1500 kHz SWITCHING FREQ-MAX, PDSO8 |
| 封装： | PLASTIC, MSOP-8 |
| 文件页数： | 2/16页 |
| 文件大小： | 154K |
| 代理商： | LT1961IMS8E#TR |
10
LT1961
1961fa
SYNCHRONIZATION
The SYNC pin, is used to synchronize the internal oscilla-
tor to an external signal. The SYNC input must pass from
a logic level low, through the maximum synchronization
threshold with a duty cycle between 20% and 80%. The
input can be driven directly from a logic level output. The
synchronizing range is equal to
initial operating frequency
up to 2MHz. This means that
minimum practical sync
frequency is equal to the worst-case
high self-oscillating
frequency (1.5MHz), not the typical operating frequency
of 1.25MHz. Caution should be used when synchronizing
above 1.7MHz because at higher sync frequencies the
amplitude of the internal slope compensation used to
prevent subharmonic switching is reduced. Higher induc-
tor values will tend to eliminate this problem. See Fre-
quency Compensation section for a discussion of an
entirely different cause of subharmonic switching before
assuming that the cause is insufficient slope compensa-
tion. Application Note 19 has more details on the theory
of slope compensation.
LAYOUT CONSIDERATIONS
As with all high frequency switchers, when considering
layout, care must be taken to achieve optimal electrical,
thermal and noise performance. For maximum efficiency,
switch rise and fall times are typically in the nanosecond
range. To prevent noise both radiated and conducted, the
APPLICATIONS INFORMATION
WU
U
high speed switching current path, shown in Figure 5,
must be kept as short as possible. This is implemented in
the suggested layout of Figure 6. Shortening this path will
also reduce the parasitic trace inductance of approxi-
mately 25nH/inch. At switch off, this parasitic inductance
produces a flyback spike across the LT1961 switch. When
operating at higher currents and output voltages, with
poor layout, this spike can generate voltages across the
LT1961 that may exceed its absolute maximum rating. A
ground plane should always be used under the switcher
circuitry to prevent interplane coupling and overall noise.
The VC and FB components should be kept as far away as
possible from the switch node. The LT1961 pinout has
been designed to aid in this. The ground for these compo-
nents should be separated from the switch current path.
Failure to do so will result in poor stability or subharmonic
like oscillation.
Board layout also has a significant effect on thermal
resistance. The exposed pad is the copper plate that runs
under the LT1961 die. This is the best thermal path for heat
out of the package. Soldering the pad onto the board will
reduce die temperature and increase the power capability
of the LT1961. Provide as much copper area as possible
around this pad. Adding multiple solder filled feedthroughs
under and around the pad to the ground plane will also
help. Similar treatment to the catch diode and inductor
terminations will reduce any additional heating effects.
1961 F05
VOUT
L1
SW
GND
LT1961
D1
C1
C3
VIN
HIGH
FREQUENCY
SWITCHING
PATH
LOAD
Figure 5. High Speed Switching Path
相关PDF资料 |
PDF描述 |
|---|---|
| LT3092ITS8#PBF | SPECIALTY ANALOG CIRCUIT, PDSO8 |
| LT3092ETS8#TRPBF | SPECIALTY ANALOG CIRCUIT, PDSO8 |
| LT3092EST#PBF | SPECIALTY ANALOG CIRCUIT, PDSO3 |
| LT3092ETS8 | SPECIALTY ANALOG CIRCUIT, PDSO8 |
| LT3092IST#PBF | SPECIALTY ANALOG CIRCUIT, PDSO3 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT1961IMS8ETRPBF | 制造商:LINER 制造商全称:Linear Technology 功能描述:1.5A, 1.25MHz Step-Up Switching Regulator |
| LT1962 | 制造商:LINER 制造商全称:Linear Technology 功能描述:Micropower Low Dropout Regulators with Shutdown |
| LT1962EMS8 | 功能描述:IC REG LDO ADJ .3A 8-MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 系列:- 产品培训模块:More Information on LDOs 标准包装:50 系列:- 稳压器拓扑结构:正，固定式 输出电压:3.3V 输入电压:最高 15V 电压 - 压降（标准）:1.1V @ 800mA 稳压器数量:1 电流 - 输出:800mA 电流 - 限制（最小）:800mA 工作温度:0°C ~ 125°C 安装类型:表面贴装 封装/外壳:TO-263-4，D²Pak（3 引线+接片），TO-263AA 供应商设备封装:D2PAK-3 包装:管件 |
| LT1962EMS8#PBF | 功能描述:IC REG LDO ADJ .3A 8-MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - 线性 系列:- 产品培训模块:MIC5365/66 Ultra-small LDO Regulators 标准包装:1 系列:- 稳压器拓扑结构:正，固定式 输出电压:3V 输入电压:最高 5.5V 电压 - 压降（标准）:0.155V @ 150mA 稳压器数量:1 电流 - 输出:150mA 电流 - 限制（最小）:200mA 工作温度:-40°C ~ 125°C 安装类型:表面贴装 封装/外壳:4-UDFN 裸露焊盘，4-TMLF? 供应商设备封装:4-TMLF?（1x1） 包装:Digi-Reel® 其它名称:576-3192-6 |
| LT1962EMS8#PBF | 制造商:Linear Technology 功能描述:Linear Voltage Regulator IC 制造商:Linear Technology 功能描述:IC, ADJ LDO REG 1.22V TO 20V 0.3A MSOP-8 |
发布紧急采购，3分钟左右您将得到回复。