- 您现在的位置：买卖IC网 > PDF目录1829 > LTC3403EDD#TRPBF (Linear Technology)IC REG BUCK SYNC ADJ 0.6A 8DFN PDF资料下载
参数资料
| 型号： | LTC3403EDD#TRPBF |
| 厂商： | Linear Technology |
| 文件页数： | 11/16页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 0.6A 8DFN |
| 标准包装： | 2,500 |
| 类型： | 降压（降压） |
| 输出类型： | 可调式 |
| 输出数： | 1 |
| 输出电压： | 0.3 V ~ 3.5 V |
| 输入电压： | 2.5 V ~ 5 V |
| PWM 型： | 电流模式，混合 |
| 频率 - 开关： | 1.5MHz |
| 电流 - 输出： | 600mA |
| 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： | 8-WFDFN 裸露焊盘 |
| 包装： | 带卷 (TR) |
| 供应商设备封装： | 8-DFN-EP（3x3） |
LTC3403
APPLICATIO S I FOR ATIO
Using Ceramic Input and Output Capacitors
Higher values, lower cost ceramic capacitors are now
becoming available in smaller case sizes. Their high ripple
DAC
10k
1000pF
LTC3403
REF
GND
current, high voltage rating and low ESR make them ideal
for switching regulator applications. Because the
LTC3403’s control loop does not depend on the output
capacitor’s ESR for stable operation, ceramic capacitors
can be used freely to achieve very low output ripple and
small circuit size.
However, care must be taken when ceramic capacitors are
used at the input and the output. When a ceramic capacitor
is used at the input and the power is supplied by a wall
adapter through long wires, a load step at the output can
induce ringing at the input, V IN . At best, this ringing can
couple to the output and be mistaken as loop instability. At
worst, a sudden inrush of current through the long wires
can potentially cause a voltage spike at V IN large enough
to damage the part.
When choosing the input and output ceramic capacitors,
choose the X5R or X7R dielectric formulations. These
dielectrics have the best temperature and voltage charac-
teristics of all the ceramics for a given value and size.
Ceramic capacitors of Y5V material are not recommended
because normal operating voltages cause their bulk ca-
pacitance to become much less than the nominal value.
Programming the Output Voltage With a DAC
Figure 3. Filtering the REF Pin
Efficiency Considerations
The efficiency of a switching regulator is equal to the
output power divided by the input power times 100%. It is
often useful to analyze individual losses to determine what
is limiting the efficiency and which change would produce
the most improvement. Efficiency can be expressed as:
Efficiency = 100% – (L1 + L2 + L3 + ...)
where L1, L2, etc. are the individual losses as a percentage
of input power.
Although all dissipative elements in the circuit produce
losses, two main sources usually account for most of the
losses in LTC3403 circuits: V IN quiescent current and I 2 R
losses. The V IN quiescent current loss dominates the
efficiency loss at very low load currents whereas the I 2 R
loss dominates the efficiency loss at medium to high load
currents. In a typical efficiency plot, the efficiency curve at
very low load currents can be misleading since the actual
power lost is of little consequence as illustrated in
Figure 4.
The output voltage can be dynamically programmed to any
voltage from 0.3V to 3.5V with an external DAC driving the
REF pin. When the output is commanded low, the output
voltage descends quickly in forced continuous mode
pulling current from the output and transferring it to the
input. If the input is not connected to a low impedance
source capable of absorbing the energy, the input voltage
could rise above the absolute maximum voltage of the part
and get damaged. The faster V OUT is commanded low, the
1
0.1
0.01
0.001
0.0001
V OUT = 1.2V
V OUT = 1.5V
V OUT = 1.8V
V OUT = 2.5V
higher is the voltage spike at the input. For best results,
ramp the REF pin from high to low as slow as the
application will allow. Avoid abrupt changes in voltage of
>0.2V/ μ s. If ramp control is unavailable, an RC filter with
a time constant of 10 μ s can be inserted between the REF
0.00001
0.1
1
10 100
LOAD CURRENT (mA)
1000
3406 F04
pin and the DAC as shown in Figure 3.
Figure 4. Power Lost vs Load Current
3403f
11
相关PDF资料 |
PDF描述 |
|---|---|
| LTC3404MPMS8#PBF | IC REG BUCK SYNC ADJ 0.6A 8MSOP |
| LTC3405ES6#TRPBF | IC REG BUCK SYNC ADJ .3A SOT23-6 |
| LTC3406BES5-1.2#TRPBF | IC REG BUCK SYNC 1.2V TSOT23-5 |
| LTC3406ES5-1.8#TRPBF | IC REG BUCK SYNC 1.8V TSOT23-5 |
| LTC3407EDD#TRPBF | IC REG BUCK SYNC ADJ 1A DL 10DFN |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3404 | 制造商:LINER 制造商全称:Linear Technology 功能描述:1.4MHz High Efficiency Monolithic Synchronous Step-Down Regulator |
| LTC3404EMS8 | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:1.24 V ~ 30 V 输入电压:1.5 V ~ 12 V PWM 型:电流模式，混合 频率 - 开关:600kHz 电流 - 输出:500mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:8-SOIC |
| LTC3404EMS8#PBF | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:250 系列:- 类型:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V 输入电压:2.05 V ~ 6 V PWM 型:电压模式 频率 - 开关:2MHz 电流 - 输出:500mA 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:6-UFDFN 包装:带卷 (TR) 供应商设备封装:6-SON（1.45x1） 产品目录页面:1032 (CN2011-ZH PDF) 其它名称:296-25628-2 |
| LTC3404EMS8#TR | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:1.24 V ~ 30 V 输入电压:1.5 V ~ 12 V PWM 型:电流模式，混合 频率 - 开关:600kHz 电流 - 输出:500mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:8-SOIC |
| LTC3404EMS8#TRPBF | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 开关稳压器 系列:- 标准包装:2,500 系列:- 类型:升压（升压） 输出类型:可调式 输出数:1 输出电压:1.24 V ~ 30 V 输入电压:1.5 V ~ 12 V PWM 型:电流模式，混合 频率 - 开关:600kHz 电流 - 输出:500mA 同步整流器:无 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:8-SOIC（0.154"，3.90mm 宽） 包装:带卷 (TR) 供应商设备封装:8-SOIC |
发布紧急采购，3分钟左右您将得到回复。