参数资料
型号: LTC3202EDD
厂商: Linear Technology
文件页数: 7/12页
文件大小: 0K
描述: IC LED DRIVR WHITE BCKLGT 10-DFN
标准包装: 121
拓扑: PWM,切换式电容器(充电泵)
输出数: 1
内部驱动器:
类型 - 主要: 背光
类型 - 次要: 白色 LED
频率: 1.5MHz
电源电压: 2.7 V ~ 4.5 V
安装类型: 表面贴装
封装/外壳: 10-WFDFN 裸露焊盘
供应商设备封装: 10-DFN(3x3)
包装: 管件
工作温度: -40°C ~ 85°C
产品目录页面: 1339 (CN2011-ZH PDF)
LTC3202
OPERATIO
(Refer to Simplified Block Diagram)
In this configuration the feedback factor ( ? V FB / ? V OUT ) will
be very near unity since the small signal LED impedance
will be considerably less than the current setting resistor
R X . Thus, this configuration will have the highest loop gain
giving it the lowest closed-loop output resistance. Like-
wise it will also require the largest amount of output
capacitance to preserve stability.
Charge Pump Strength
Figure 3 shows how the LTC3202 can be modeled as a
Thevenin equivalent circuit to determine the amount of
current available from the effective input voltage, 1.5V IN
and the effective open-loop output resistance, R OL .
For fixed voltage applications, the output voltage can be
set by the ratio of two resistors and the feedback control
R OL
+
voltage as shown in Figure 2. The output voltage is given
+
1.5V IN
V OUT
by the set point voltage times the gain factor 1 + R 1 /R 2 .
Note that the closed-loop output resistance will increase in
proportion to the loop gain consumed by the resistive
divider ratio. For example, if the resistor ratio is 2:1 giving
a gain of 3, the closed-loop output resistance will be about
3 times higher than its nominal gain of 1 value. Given that
the closed-loop output resistance is about 0.35 ? with a
3202 F03
Figure 3. Equivalent Open-Loop Circuit
From Figure 3 the available current is given by:
gain of 1, the closed-loop output resistance will be about
1 ? when using a gain of 3.
I OUT =
1.5 V IN – V OUT
R OL
V OUT
3
V OUT = V FB (1 +
R1
R2
)
Typical values of R OL as a function of temperature are
shown in Figure 4.
LTC3202
R1
FB
GND
5, 11
2
1 μ F
R2
4.8
4.6
V FB = 0
I L = 100mA
C1 = C2 = 1 μ F
R OL = (1.5V IN – V OUT )/I L
3202 F02
4.4
Figure 2. Voltage Control Mode
When using the LTC3202 in voltage control mode, any of
the three voltage settings (0.2V, 0.4V or 0.6V) can be used
4.2
4.0
V IN = 2.7V
V IN = 3.6V
as the set point voltage. For optimum noise performance
and lowest closed-loop output resistance the highest
voltage setting will likely be the most desirable.
3.8
–40
–15
10 35
TEMPERATURE ( ° C)
60
85
3202 F04
Typical values for total voltage divider resistance can
range from several k ? s up to 1M ? .
Figure 4. Typical R OL vs Temperature
3202fa
7
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相关代理商/技术参数
参数描述
LTC3202EDD#PBF 功能描述:IC LED DRIVR WHITE BCKLGT 10-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:60 系列:- 恒定电流:- 恒定电压:- 拓扑:线性(LDO),PWM,升压(升压) 输出数:8 内部驱动器:是 类型 - 主要:背光 类型 - 次要:RGB,白色 LED 频率:500kHz ~ 1.5MHz 电源电压:4.75 V ~ 26 V 输出电压:45V 安装类型:* 封装/外壳:* 供应商设备封装:* 包装:* 工作温度:-40°C ~ 85°C
LTC3202EDD#TR 功能描述:IC LED DRIVR WHITE BCKLGT 10-DFN RoHS:否 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3202EDD#TRPBF 功能描述:IC LED DRIVR WHITE BCKLGT 10-DFN RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3202EMS 功能描述:IC LED DRVR WHITE BCKLGT 10-MSOP RoHS:否 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND
LTC3202EMS#PBF 功能描述:IC LED DRVR WHITE BCKLGT 10-MSOP RoHS:是 类别:集成电路 (IC) >> PMIC - LED 驱动器 系列:- 标准包装:6,000 系列:- 恒定电流:- 恒定电压:- 拓扑:开路漏极,PWM 输出数:4 内部驱动器:是 类型 - 主要:LED 闪烁器 类型 - 次要:- 频率:400kHz 电源电压:2.3 V ~ 5.5 V 输出电压:- 安装类型:表面贴装 封装/外壳:8-VFDFN 裸露焊盘 供应商设备封装:8-HVSON 包装:带卷 (TR) 工作温度:-40°C ~ 85°C 其它名称:935286881118PCA9553TK/02-TPCA9553TK/02-T-ND