- 您现在的位置：买卖IC网 > PDF目录14101 > LTC3403EDD (Linear Technology)IC REG BUCK SYNC ADJ 0.6A 8DFN PDF资料下载
参数资料
| 型号： | LTC3403EDD |
| 厂商： | Linear Technology |
| 文件页数： | 8/16页 |
| 文件大小： | 0K |
| 描述： | IC REG BUCK SYNC ADJ 0.6A 8DFN |
| 标准包装： | 121 |
| 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： | 管件 |
| 供应商设备封装： | 8-DFN-EP（3x3） |
LTC3403
OPERATIO
Main Control Loop
(Refer to Functional Diagram)
ing the BURST comparator to trip and turn the top switch
The LTC3403 uses a constant frequency, current mode
step-down architecture. The main (P-channel MOSFET),
synchronous (N-channel MOSFET) and bypass (P-chan-
nel MOSFET) switches are internal. During normal opera-
tion, the internal main switch is turned on each cycle when
the oscillator sets the RS latch, and turned off when the
current comparator, I COMP , resets the RS latch. The peak
inductor current at which I COMP resets the RS latch, is
controlled by the output of error amplifier EA. When the
load current increases, it causes a slight decrease in the
feedback voltage, FB, relative to the external reference,
which in turn, causes the EA amplifier’s output voltage to
increase until the average inductor current matches the
new load current. While the main switch is off, the syn-
chronous switch is turned on until the beginning of the
next clock cycle.
In forced continuous mode the inductor current is con-
stantly cycled. In this mode, the output voltage can re-
spond quickly to the external reference voltage by sourc-
ing or sinking current as needed.
Burst Mode Operation
The LTC3403 is capable of Burst Mode operation in which
the internal power switches operate intermittently based
on load demand.
In Burst Mode operation, the peak current of the inductor
is set to approximately 200mA regardless of the output
load. Each burst event can last from a few cycles at light
loads to almost continuously cycling with short sleep
intervals at moderate loads. In between these burst events,
the power switches and any unneeded circuitry are turned
off, reducing the quiescent current to 20 μ A. In this sleep
state, the load current is being supplied solely from the
output capacitor. As the output voltage droops, the EA
amplifier’s output rises above the sleep threshold signal-
on. This process repeats at a rate that is dependent on the
load demand.
Controlling the Output Voltage
The output voltage can be dynamically programmed from
0.3V to 3.5V using the REF input. Because the gain to V OUT
from REF is internally set to 3, the corresponding input
range at REF is 0.1V to 1.167V. V OUT can be modulated
during operation by driving REF with an external DAC.
When REF exceeds 1.2V, an internal bypass P-channel
MOSFET connects V IN to V OUT , dramatically reducing the
drop across the inductor and the main switch.
Dropout Operation
If the reference voltage would cause V OUT to exceed V IN ,
the LTC3403 enters dropout operation. During dropout,
the main switch remains on continuously and operates at
100% duty cycle. If the voltage at REF is less than 1.2V, the
bypass P-channel MOSFET will stay off even in dropout
operation. The output voltage is then determined by the
input voltage minus the voltage drop across the main switch
and the inductor.
An important detail to remember is that at low input
supply voltages, the R DS(ON) of the P-channel switch
increases (see Typical Performance Characteristics).
Therefore, the user should calculate the power dissipa-
tion when the LTC3403 is used at 100% duty cycle with
low input voltage (See Thermal Considerations in the
Applications Information section).
Low Supply Operation
The LTC3403 will operate with input supply voltages as
low as 2.5V, but the maximum allowable output current is
reduced at this low voltage. Figure 2 shows the reduction
in the maximum output current as a function of input
voltage for various output voltages.
3403f
8
相关PDF资料 |
PDF描述 |
|---|---|
| VI-BNN-EW-F3 | CONVERTER MOD DC/DC 18.5V 100W |
| LNC2W822MSEJ | CAP ALUM 8200UF 450V 20% SCREW |
| 12LRS224C | INDUCTOR RAD 220UH .78A T/H 10X8 |
| CGS642T350X5C | CAP ALUM 6400UF 350V SCREW |
| MAX6868UK22D5L+T | IC MPU SUPERVISOR SOT23-5 |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LTC3403EDD#PBF | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8DFN 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 |
| LTC3403EDD#TR | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8DFN 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 |
| LTC3403EDD#TRPBF | 功能描述:IC REG BUCK SYNC ADJ 0.6A 8DFN 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 |
| 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 |
发布紧急采购，3分钟左右您将得到回复。