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参数资料
| 型号： | LM3647IMX |
| 厂商： | NATIONAL SEMICONDUCTOR CORP |
| 元件分类： | 电源管理 |
| 英文描述： | 1-CHANNEL POWER SUPPLY SUPPORT CKT, PDSO20 |
| 封装： | PLASTIC, SOIC-20 |
| 文件页数： | 14/14页 |
| 文件大小： | 271K |
| 代理商： | LM3647IMX |
4.0 Functional Description (Continued)
10131815
The charge current duty cycles for the different phases
cycles are listed below:
Charge Phase
Charge Current Duty
Cycle
Soft Start
10%
Fast Charge
100%
Topping Charge
10%
Maintenance Charge
5%
4.3.4 Dimensioning the Reset Circuitry
The reset-circuitry is designed to hold the RESET pin low
until the power supply to the LM3647 has stabilized. The
RC-network (R21 and C4) should be dimensioned in the
following way:
(R21 x C4) > 5xPowerSupplyRiseTime
The diode D2 discharges the capacitance C4 when power
loss occurs. The resistor R20 is used to protect the SYSOK-
pin, and its value is not critical (typical value is 2 k
). R20
can be eliminated if the SYSOK pin is not connected to
RESET or if the value of C4 is
≤0.1 F. The connection
between RESET and SYSOK is optional but highly recom-
mended for safe operation of the LM3647.
10131816
4.3.5 Dimensioning the RCIN Circuitry
The RC-circuitry is designed to time the charger so it
charges and regulates at the correct frequency. The values
of the R and C are important, because a change in the
RC-value gives a higher or lower operating frequency which
affects charge quality. The capacitance should be a ceramic
type and preferably an NP0 type, which gives the least
frequency deviation with temperature change.
10131817
4.3.6 Dimensioning the DISCHARGE Circuitry
The discharge-circuitry controls the discharge rate during the
discharge phase (if used). The discharge output turns on the
transistor Q2, and a current flows from the battery through
the discharge resistor R8. The current through R8 depends
on battery voltage and the value of R8. This value depends
on the maximum discharge rate for the battery pack. The
approximate value can be calculated using the formula be-
low:
The resistor R7 keeps the transistor Q2 off until the LM3647
has been powered up and is in control of the circuitry.
10131819
LM3647
www.national.com
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相关代理商/技术参数 |
参数描述 |
|---|---|
| LM3647M | 制造商:未知厂家 制造商全称:未知厂家 功能描述:Battery Management |
| LM3648EVM | 功能描述:LM3648 1, Non-Isolated Output LED Driver Evaluation Board 制造商:texas instruments 系列:- 零件状态:有效 电流 - 输出/通道:1.5A 输出和类型:1，非隔离 电压 - 输出:- 特性:I2C 电压 - 输入:2.5 V ~ 5.5 V 所含物品:板 使用的 IC/零件:LM3648 标准包装:1 |
| LM3648TTYFFR | 功能描述:LED 驱动器 IC 1 输出 DC DC 稳压器 升压（升压） 调光 1.5A（闪存） 12-DSBGA 制造商:texas instruments 系列:- 包装:剪切带（CT） 零件状态:在售 类型:DC DC 稳压器 拓扑:升压（升压） 内部开关:是 输出数:1 电压 - 供电（最低）:2.5V 电压 -?供电（最高）:5.5V 电压 - 输出:- 电流 - 输出/通道:1.5A（闪存） 频率:4MHz 调光:- 应用:照相机闪光灯 工作温度:-40°C ~ 85°C（TA） 安装类型:表面贴装 封装/外壳:12-UFBGA，DSBGA 供应商器件封装:12-DSBGA 标准包装:1 |
| LM3648YFFR | 功能描述:LED 驱动器 IC 1 输出 DC DC 稳压器 升压（升压） 1.5A（闪存） 12-DSBGA 制造商:texas instruments 系列:- 包装:剪切带（CT） 零件状态:有效 类型:DC DC 稳压器 拓扑:升压（升压） 内部开关:是 输出数:1 电压 - 供电（最低）:2.5V 电压 -?供电（最高）:5.5V 电压 - 输出:- 电流 - 输出/通道:1.5A（闪存） 频率:4MHz 调光:- 应用:照相机闪光灯 工作温度:-40°C ~ 85°C（TA） 安装类型:表面贴装 封装/外壳:12-UFBGA，DSBGA 供应商器件封装:12-DSBGA 标准包装:1 |
| LM3649MHE-AA/NOPB | 制造商:Texas Instruments 功能描述: |
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