- 您现在的位置：买卖IC网 > PDF目录14049 > LT1425CS (Linear Technology)IC REG FLYBK ISOLATED .2A 16SOIC PDF资料下载
参数资料
| 型号： | LT1425CS |
| 厂商： | Linear Technology |
| 文件页数： | 16/20页 |
| 文件大小： | 0K |
| 描述： | IC REG FLYBK ISOLATED .2A 16SOIC |
| 标准包装： | 50 |
| 类型： | 回扫，隔离 |
| 输出数： | 1 |
| 输入电压： | 2.8 V ~ 20 V |
| PWM 型： | 电流模式 |
| 频率 - 开关： | 285kHz |
| 电流 - 输出： | 200mA |
| 同步整流器： | 无 |
| 工作温度： | 0°C ~ 100°C |
| 安装类型： | 表面贴装 |
| 封装/外壳： | 16-SOIC（0.154"，3.90mm 宽） |
| 包装： | 管件 |
| 供应商设备封装： | 16-SOIC |
LT1425
APPLICATIO N S I N FOR M ATIO N
) )
I IN = 7mA + DC SW
Average supply current (including driver current) is:
I
35
where,
I SW = Switch current
DC = On switch duty cycle
Switch power dissipation is given by:
P SW = (I SW ) 2 (R SW )(DC)
R SW = Output switch ON resistance
Total power dissipation of the die is the sum of supply
current times supply voltage plus switch power:
P D(TOTAL) = (I IN ? V IN ) + P SW
FREQUENCY COMPENSATION
Loop frequency compensation is performed by connect-
ing a capacitor from the output of the error amplifier (V C
pin) to ground. An additional series resistor, often
required in traditional current mode switcher controllers
is usually not required, and can even prove detrimental.
The phase margin improvement traditionally offered by
this extra resistor will usually be already accomplished by
the nonzero secondary circuit impedance, which adds a
next cycle. This action naturally holds the V C voltage stable
during the current comparator sense action (current mode
switching).
PCB LAYOUT CONSIDERATIONS
For maximum efficiency, switch rise and fall times are
made as short as practical. To prevent radiation and high
frequency resonance problems, proper layout of the com-
ponents connected to the IC is essential, especially the
power paths (primary and secondary). B field (magnetic)
radiation is minimized by keeping output diode, switch pin
and output bypass capacitor leads as short as possible. E
field radiation is kept low by minimizing the length and
area of all traces connected to the switch pin. A ground
plane should always be used under the switcher circuitry
to prevent interplane coupling.
The high speed switching current paths are shown sche-
matically in Figure 2. Minimum lead length in these paths
are essential to ensure clean switching and minimal EMI.
The path containing the input capacitor, transformer pri-
mary, output switch, the path containing the transformer
secondary, output diode and output capacitor are the only
ones containing nanosecond rise and fall times. Keep
these paths as short as possible.
V OUT
“zero” to the loop response.
In further contrast to traditional current mode switchers,
V IN
HIGH
FREQUENCY
CIRCULATING
?
?
HIGH
FREQUENCY
CIRCULATING
PATH
ISOLATED
LOAD
V C pin ripple is generally not an issue with the LT1425. The
dynamic nature of the clamped feedback amplifier forms
an effective track/hold type response, whereby the V C
voltage changes during the flyback pulse, but is then
“held” during the subsequent “switch ON” portion of the
16
PATH
Figure 2
F
1425 F02
相关PDF资料 |
PDF描述 |
|---|---|
| MAX6868UK43D5S+T | IC MPU SUPERVISOR SOT23-5 |
| MAX6868UK44D3L+T | IC MPU SUPERVISOR SOT23-5 |
| MAX6868UK44D3S+T | IC MPU SUPERVISOR SOT23-5 |
| MAX6868UK43D6L+T | IC MPU SUPERVISOR SOT23-5 |
| RGM24DTKS | CONN EDGECARD 48POS DIP .156 SLD |
相关代理商/技术参数 |
参数描述 |
|---|---|
| LT1425CS#PBF | 功能描述:IC REG FLYBK ISOLATED .2A 16SOIC 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 |
| LT1425CS#TR | 功能描述:IC REG FLYBK ISOLATED .2A 16SOIC 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:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V，1.5V，1.8V，2.5V 输入电压:2.7 V ~ 20 V PWM 型:- 频率 - 开关:- 电流 - 输出:50mA 同步整流器:是 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:带卷 (TR) 供应商设备封装:10-MSOP 裸露焊盘 |
| LT1425CS#TRPBF | 功能描述:IC REG FLYBK ISOLATED .2A 16SOIC 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:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V，1.5V，1.8V，2.5V 输入电压:2.7 V ~ 20 V PWM 型:- 频率 - 开关:- 电流 - 输出:50mA 同步整流器:是 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:带卷 (TR) 供应商设备封装:10-MSOP 裸露焊盘 |
| LT1425CSPBF | 制造商:Linear Technology 功能描述:LT1425CSPBF |
| LT1425IS | 功能描述:IC REG FLYBK ISOLATED .2A 16SOIC 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:降压（降压） 输出类型:固定 输出数:1 输出电压:1.2V，1.5V，1.8V，2.5V 输入电压:2.7 V ~ 20 V PWM 型:- 频率 - 开关:- 电流 - 输出:50mA 同步整流器:是 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:带卷 (TR) 供应商设备封装:10-MSOP 裸露焊盘 |
发布紧急采购，3分钟左右您将得到回复。