参数资料
型号: LM3420M5X-16.8/NOPB
厂商: NATIONAL SEMICONDUCTOR CORP
元件分类: 电源管理
英文描述: 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO5
封装: MINIATURE, SOT-23, 5 PIN
文件页数: 2/17页
文件大小: 441K
代理商: LM3420M5X-16.8/NOPB
Five Lead Surface Mount Package Information
The small SOT23-5 package allows only 4 alphanumeric
characters to identify the product. The table below contains
the field information marked on the package.
The first letter “D” identifies the part as a Driver, the next two
numbers indicate the voltage, “02” for a 4.2V part, “07” for an
8.2V part, “03” for an 8.4V part, “04” for a 12.6V part, and
“05” for a 16.8V part. The fourth letter indicates the grade,
“B” for standard grade, “A” for the prime grade.
The SOT23-5 surface mount package is only available on
tape in quantity increments of 1000 on tape and reel (indi-
cated by the letters “M5” in the part number), or in quantity
increments of 3000 on tape and reel (indicated by the letters
“M5X” in the part number).
Product Description
The LM3420 is a shunt regulator specifically designed to be
the reference and control section in an overall feedback loop
of a Lithium-Ion battery charger. The regulated output volt-
age is sensed between the IN pin and GROUND pin of the
LM3420. If the voltage at the IN pin is less than the LM3420
regulating voltage (V
REG), the OUT pin sources no current.
As the voltage at the IN pin approaches the V
REG voltage,
the OUT pin begins sourcing current. This current is then
used to drive a feedback device (opto-coupler), or a power
device (linear regulator, switching regulator, etc.), which ser-
vos the output voltage to be the same value as V
REG.
In some applications, (even under normal operating condi-
tions) the voltage on the IN pin can be forced above the
V
REG voltage. In these instances, the maximum voltage
applied to the IN pin should not exceed 20V. In addition, an
external resistor may be required on the OUT pin to limit the
maximum current to 20 mA.
Compensation
The inverting input of the error amplifier is brought out to
allow overall closed-loop compensation. In many of the ap-
plications circuits shown here, compensation is provided by
a single capacitor (C
C) connected from the compensation
pin to the out pin of the LM3420. The capacitor values shown
in the schematics are adequate under most conditions, but
they can be increased or decreased depending on the de-
sired loop response. Applying a load pulse to the output of a
regulator circuit and observing the resultant output voltage
response is an easy method of determining the stability of
the control loop.
Analyzing more complex feedback loops requires additional
information.
The formula for AC gain at a frequency (f) is as follows;
Voltage
Grade
Order
Package
Supplied as
Information
Marking
4.2V
A (Prime)
LM3420AM5-4.2
D02A
1000 unit increments on tape and reel
4.2V
A (Prime)
LM3420AM5X-4.2
D02A
3000 unit increments on tape and reel
4.2V
B (Standard)
LM3420M5-4.2
D02B
1000 unit increments on tape and reel
4.2V
B (Standard)
LM3420M5X-4.2
D02B
3000 unit increments on tape and reel
8.2V
A (Prime)
LM3420AM5-8.2
D07A
1000 unit increments on tape and reel
8.2V
A (Prime)
LM3420AM5X-8.2
D07A
3000 unit increments on tape and reel
8.2V
B (Standard)
LM3420M5-8.2
D07B
1000 unit increments on tape and reel
8.2V
B (Standard)
LM3420M5X-8.2
D07B
3000 unit increments on tape and reel
8.4V
A (Prime)
LM3420AM5-8.4
D03A
1000 unit increments on tape and reel
8.4V
A (Prime)
LM3420AM5X-8.4
D03A
3000 unit increments on tape and reel
8.4V
B (Standard)
LM3420M5-8.4
D03B
1000 unit increments on tape and reel
8.4V
B (Standard)
LM3420M5X-8.4
D03B
3000 unit increments on tape and reel
12.6V
A (Prime)
LM3420AM5-12.6
D04A
1000 unit increments on tape and reel
12.6V
A (Prime)
LM3420AM5X-12.6
D04A
3000 unit increments on tape and reel
12.6V
B (Standard)
LM3420M5-12.6
D04B
1000 unit increments on tape and reel
12.6V
B (Standard)
LM3420M5X-12.6
D04B
3000 unit increments on tape and reel
16.8V
A (Prime)
LM3420AM5-16.8
D05A
1000 unit increments on tape and reel
16.8V
A (Prime)
LM3420AM5X-16.8
D05A
3000 unit increments on tape and reel
16.8V
B (Standard)
LM3420M5-16.8
D05B
1000 unit increments on tape and reel
16.8V
B (Standard)
LM3420M5X-16.8
D05B
3000 unit increments on tape and reel
FIGURE 1. SOT23-5 Marking
LM3420-4.2/LM3420-8.2/LM3420-8.4/LM3420-12.6/LM3420-16.8
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相关PDF资料
PDF描述
LM3420AM5-4.2/NOPB 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO5
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LM3420M5X-4.2 功能描述:IC CTRLR LI-ION BAT CHRG SOT23-5 RoHS:是 类别:集成电路 (IC) >> PMIC - 电池管理 系列:- 标准包装:1 系列:- 功能:充电管理 电池化学:锂离子(Li-Ion)、锂聚合物(Li-Pol) 电源电压:3.75 V ~ 6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SC-74A,SOT-753 供应商设备封装:SOT-23-5 包装:剪切带 (CT) 产品目录页面:669 (CN2011-ZH PDF) 其它名称:MCP73831T-2ACI/OTCT
LM3420M5X-8.2 功能描述:IC CTRLR LI-ION BAT CHRG SOT23-5 RoHS:是 类别:集成电路 (IC) >> PMIC - 电池管理 系列:- 标准包装:1 系列:- 功能:充电管理 电池化学:锂离子(Li-Ion)、锂聚合物(Li-Pol) 电源电压:3.75 V ~ 6 V 工作温度:-40°C ~ 85°C 安装类型:表面贴装 封装/外壳:SC-74A,SOT-753 供应商设备封装:SOT-23-5 包装:剪切带 (CT) 产品目录页面:669 (CN2011-ZH PDF) 其它名称:MCP73831T-2ACI/OTCT
LM3420M5X-8.4 功能描述:电池管理 RoHS:否 制造商:Texas Instruments 电池类型:Li-Ion 输出电压:5 V 输出电流:4.5 A 工作电源电压:3.9 V to 17 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:VQFN-24 封装:Reel
LM3420M5X-8.4/NOPB 功能描述:电池管理 RoHS:否 制造商:Texas Instruments 电池类型:Li-Ion 输出电压:5 V 输出电流:4.5 A 工作电源电压:3.9 V to 17 V 最大工作温度:+ 85 C 最小工作温度:- 40 C 封装 / 箱体:VQFN-24 封装:Reel
LM3421 制造商:NSC 制造商全称:National Semiconductor 功能描述:N-Channel Controllers for Constant Current LED Drivers