LM3647IM National Semiconductor, LM3647IM Datasheet
LM3647IM
Specifications of LM3647IM
*LM3647IM/NOPB
LM3647IM/NOPB
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LM3647IM Summary of contents
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... When using an external current source, the current is con- trolled by the LM3647 which turns the current source on and off. The LM3647 automatically detects the presence of a © 2004 National Semiconductor Corporation battery and starts the charging procedure when the battery is installed. Whenever an error occurs (e.g., short circuit, tem- perature too high, temperature too low, bad battery, charge time over, etc ...
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... BUZZER 18 PWM 19 SEL1 20 SEL2 Device LM3647 www.national.com 10131802 Top View Order Number LM3647IM See NS Package Number M20B I/O I Input to Select Power Source or Li-Ion Cell Voltage I Input to Select Maintenance Charge Time Out, Connected to an RC-Network RC-Timing Pin Ground 5V, Power Supply I Reset Pin, Active Low ...
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Typical Application 3 10131801 www.national.com ...
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... Electrical Characteristics Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Supply Voltage ( Voltage at Any Pin Total Current into V Pin (Source Electrical Characteristics −40˚C ≤ T ≤ +85˚C unless otherwise specified. ...
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Functional Description 4.1 GENERAL The LM3647 can be configured to charge three different types of batteries: Ni-Cd, Ni-MH and Li-Ion. The charger behavior for Ni-Cd and Ni-MH is similar but the charge curves will appear slightly different due to ...
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Functional Description tied to V (PWM “fast” frequency constant current CC source when tied to GND (PWM “slow” frequency). When configured for Li-Ion batteries, SEL3 switches between 4.1V cells or 4.2V cells. Note: SEL3 must be hard ...
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Functional Description Resistor network selection Quick Guide: Ni-Cd/Ni-MH No. of Cells Nominal Max 2 2.4V 3.7V 3 3.6V 5.55V 4 4.8V 7. 9.25V 6 7.2V 11.1V 7 8.4V 12.95V 8 9.6V 14.8V 9 10.8V 16.65V 10 12V ...
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Functional Description 4.3.3 Charge Current Charge current selection depends on the type of power supply used. The LM3647 supports two types: current feed- back and constant current. The PWM pin is used to control the power supply and depending ...
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Functional Description The charge current duty cycles for the different phases cycles are listed below: Charge Phase Charge Current Duty Soft Start Fast Charge Topping Charge Maintenance Charge 4.3.4 Dimensioning the Reset Circuitry The reset-circuitry is designed to hold ...
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Functional Description 4.3.7 BUZZER Output Circuitry The buzzer-circuitry turns the transistor Q3 on when the buzzer should sound. If the current consumption for the buzzer is lower than 0.3 mA then the buzzer may be directly connected to the ...
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Functional Description Typical Configuration Curve, (NTC Characteristics: 3 kΩ 4.4 TYPICAL CIRCUIT CONFIGURATIONS 4.4.1 Common Circuitry Used for both Ni-Cd/Ni-MH and Li-Ion (Continued 25˚C, β=3988) 10131821 10131822 www.national.com ...
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Functional Description 4.4.2 Circuitry Used Only for Ni-Cd/Ni-MH www.national.com (Continued) 12 10131823 ...
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Functional Description 4.4.3 Circuitry Used for Li-Ion (can also be used for Ni-Cd and Ni-MH if those chemestries are to be supported with the same charger) Note required to protect Q4 from reverse current. (Continued) 13 10131824 ...
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... Deutsch Tel: +49 (0) 69 9508 6208 English www.national.com Français Tel: +33 ( 8790 Molded SO Wide Body Package (WM) Order Number LM3647IM NS Package Number M20B 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system affect its safety or effectiveness ...