参数资料
型号: LT3741IUF#PBF
厂商: LINEAR TECHNOLOGY CORP
元件分类: 稳压器
英文描述: SWITCHING CONTROLLER, 1070 kHz SWITCHING FREQ-MAX, PQCC20
封装: 4 X 4 MM, LEAD FREE, PLASTIC, MO-220WGGD-1, QFN-20
文件页数: 8/24页
文件大小: 243K
代理商: LT3741IUF#PBF
LT3741
16
3741fb
Output Current Regulation
To adjust the regulated load current, an analog voltage is
applied to the CTRL1 pin. Figure 5 shows the regulated
voltage across the sense resistor for control voltages
up to 2V. Figure 6 shows the CTRL1 voltage created by
a voltage divider from VREF to ground. When sizing the
resistor divider, please be aware that the VREF pin is current
limited to 500μA. Above 1.5V, the control voltage has no
effect on the regulated inductor current.
APPLICATIONS INFORMATION
LT3741
VREF
R2
R1
3741 F06
CTRL1
Figure 5. Sense Voltage vs CTRL Voltage
Figure 6. Analog Control of Inductor Current
VCTRL (V)
0
V
SENSE
+
V
SENSE
(mV)
10
20
30
40
50
60
0.5
1.0
1.5
3741 F05
2.0
not leave this pin open under any condition. The RT pin
is also current limited to 60μA. See Table 4 and Figure 8
for resistor values and the corresponding switching
frequencies.
Table 4. Switching Frequency
SWITCHING FREQUENCY (MHz)
RT (kΩ)
1
40.2
0.750
53.6
0.5
82.5
0.3
143
0.2
200
Figure 7. Output Voltage Regulation and Overvoltage Protection
Feedback Connections
LT3741
R2
VOUT
R1
3741 F07
FB
RT (kΩ)
0
FREQUENCY
(MHz)
0.4
0.8
1.2
0.2
0.6
1.0
100
200
300
400
3743 F08
500
50
0
150
250
350
450
Figure 8. Frequency vs RT Resistance
Voltage Regulation and Overvoltage Protection
The LT3741 uses the FB pin to regulate the output voltage
and to provide a high speed overvoltage lockout to avoid
high voltage conditions. The regulated output voltage
is programmed using a resistor divider from the output
and ground (Figure 7). When the output voltage exceeds
125% of the regulated voltage level (1.5V at the FB pin),
the internal overvoltage ag is set, terminating switching.
The regulated output voltage must be greater than 1.5V
and is set by the equation:
V
OUT = 1.21V 1+
R2
R1
Programming Switching Frequency
The LT3741 has an operational switching frequency range
between 200kHz and 1MHz. This frequency is programmed
with an external resistor from the RT pin to ground. Do
相关PDF资料
PDF描述
LT3748HMS#PBF SWITCHING CONTROLLER, PDSO12
LT3758HMSE#TRPBF SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO10
LT3758MPMSE#PBF SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO10
LT3758HMSE#PBF SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO10
LT3758MPMSE#TRPBF SWITCHING REGULATOR, 1000 kHz SWITCHING FREQ-MAX, PDSO10
相关代理商/技术参数
参数描述
LT3741IUF-TRPBF 制造商:LINER 制造商全称:Linear Technology 功能描述:High Power, Constant Current, Constant Voltage, Step-Down Controller
LT3742 制造商:LINER 制造商全称:Linear Technology 功能描述:Dual, 2-Phase Step-Down Switching Controller
LT3742_1 制造商:LINER 制造商全称:Linear Technology 功能描述:Dual, 2-Phase Step-Down Switching Controller Programmable Soft-Start
LT3742EUF#PBF 功能描述:IC REG CTRLR BUCK PWM CM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 特色产品:LM3753/54 Scalable 2-Phase Synchronous Buck Controllers 标准包装:1 系列:PowerWise® PWM 型:电压模式 输出数:1 频率 - 最大:1MHz 占空比:81% 电源电压:4.5 V ~ 18 V 降压:是 升压:无 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-5°C ~ 125°C 封装/外壳:32-WFQFN 裸露焊盘 包装:Digi-Reel® 产品目录页面:1303 (CN2011-ZH PDF) 其它名称:LM3754SQDKR
LT3742EUF#TRPBF 功能描述:IC REG CTRLR BUCK PWM CM 24-QFN RoHS:是 类别:集成电路 (IC) >> PMIC - 稳压器 - DC DC 切换控制器 系列:PolyPhase® 标准包装:2,500 系列:- PWM 型:电流模式 输出数:1 频率 - 最大:500kHz 占空比:96% 电源电压:4 V ~ 36 V 降压:无 升压:是 回扫:无 反相:无 倍增器:无 除法器:无 Cuk:无 隔离:无 工作温度:-40°C ~ 125°C 封装/外壳:24-WQFN 裸露焊盘 包装:带卷 (TR)