NCP1835 ON Semiconductor, NCP1835 Datasheet
NCP1835
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NCP1835 Summary of contents
Page 1
... Its low input voltage capability, adjustable charge current, ability to maintain regulation without a battery, and its onboard thermal foldback make it versatile enough to charge from a variety of wall adapters. The NCP1835 can charge from a standard voltage−source wall adapter as a CCCV charger, or from a current limited adapter to limit power dissipation in the pass device. ...
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... FCHG I = (0.1*I EOC FCHG 9 VSNS Battery voltage sense pin. Connect this as close as possible to the battery input connection. Charge current output. A minimum 4.7 mF capacitor is needed for stability when the battery is not attached. 10 BAT NCP1835 CFLG EN V2P8 VSNS FAULT BAT V CC ISEL TIMER GND 0.1 mF ...
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... PCB that has 1 single signal layer with the additional 3 solid ground or power planes. The maximum package power dissipation limit must not be exceeded: T J(max qJA with R = 68.5°C/ 100°C, P qJA J(max) 4. Moisture Sensitivity Level per IPC/JEDEC standard: J−STD−020A. NCP1835 Symbol V FAULT is highly dependent on the PCB heatsink area. For example, R qJA = 1. http://onsemi.com 3 Value ...
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... FAULT Pin Recommended Maximum Operating Voltage CFLG Pin Sink Current (V = 0.8 V) CFLG FAULT Pin Sink Current (V = 0.8 V) FAULT 5. Guaranteed by design. Not tested in production. NCP1835 (Typical values are tested 5.0 V and room temperature, maximum and minimum values 3.7 V) ISEL BAT ...
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... 4.05 V floating BAT 4.00 −50 − AMBIENT TEMPERATURE (°C) A Figure 4. Regulated Output Voltage vs. Temperature 3. 2.95 I V2P8 2.90 2.85 2.80 2.75 2.70 4.5 Figure 6. V2P8 Voltage vs. Input Voltage NCP1835 4.30 4.25 4.20 4.15 4.10 4. ISEL 4.00 0.8 1 4.5 Figure 3. Regulated Output Voltage (floating) vs. 0.80 0.78 0.76 0.74 0. 3.7 V BAT ISEL 0.70 75 100 125 4.5 Figure 5. ISEL Voltage vs. Input Voltage ...
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... V BAT 60 −50 − AMBIENT TEMPERATURE (°C) A Figure 9. Trickle Charge Current vs. Temperature 4.10 4.05 4.00 3.95 3.90 4.5 5.0 5 INPUT VOLTAGE (V) CC Figure 11. Recharge Voltage vs. Input Voltage NCP1835 120 110 100 3.7 V BAT V = 2.0 V BAT ISEL ISEL 80 5.1 5.3 5.5 4.5 Figure 8. Trickle Charge Current vs. Input Voltage 1200 1100 ...
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... NCP1835 and Figure 14 graphically illustrates this. When the charger is powered up and the input voltage rises above the power−on, rising threshold (nominally 3.4 V), the charger initiates the charging cycle. The NCP1835 first determines the cell voltage less than the pre−charge threshold (2.8 V), the IC NCP1835 DETAILED OPERATING DESCRIPTION recognizes the battery as severely discharged. In this state, the NCP1835 pre− ...
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... 1/8 TIMEOUT? Constant Y Trickle Current Charge Charge Set FAULT Low Latch Up Charger N EN Toggled? Y End−of−Charge or FAULT Figure 13. Charging Flow Chart NCP1835 Charging Flow Chart CC Charge ≥ SNS REG TIMEOUT Constant Voltage Charge EOC Indication; Set CFLG High ...
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... I charge I PC CFLG FAULT V2P8 0 Table 1. Charge Status Condition Trickle, Constant Current and Constant Voltage Charge End−of−Charge or Shutdown Mode Timeout Fault, V < 0. > 1.4 V ISEL ISEL NCP1835 CC CV End of Charge Charge Charge Inhibit V V REG REG V RECH I CHG I EOC 2 ...
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... This voltage can also be used to power a microprocessor I/O. NCP1835 Enable/Disable (EN) Pulling the EN pin to GND disables the NCP1835. In shutdown mode, the internal reference, oscillator, and control circuits are all turned off. This reduces the battery drain current to less than 3.0 mA and the input supply current ...
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... A 4 higher value ceramic capacitor is recommended for the input bypass capacitor. For the output capacitor, when there is no battery inserted and the NCP1835 is used as an LDO with 4 4.242 V output voltage higher value tantalum capacitor is recommended for stability. With the battery attached, the output capacitor can be any type with the value higher than 0 ...
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... Charging with Constant Voltage Adapters or Current Limited Adapters The NCP1835 can be powered from two types of regulated adapters: a traditional constant voltage type or a current limited type. Figure 18 illustrates the operation of Trickle CC ...
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... The copper pad is the primary heatsink and should be connected to as much top layer metal as possible to minimize the thermal impedance. Figure 20 illustrates graphically the recommended connection for the exposed pad with vias. The following is a NCP1835 Demo Board Schematic, Layout, and suggested Bill of Materials (T8) R4 ...
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... NCP1835 Figure 22. Silkscreen Layer Figure 23. Top Layer Figure 24. Bottom Layer http://onsemi.com 14 ...
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... Table 4. Bill of Materials Item Qty. Part Description 1 1 NCP1835 Integrated Li−Ion Charger (DFN−10) Chip Resistor " (0603 Chip Resistor "1% 160 kW (0603 Chip Resistor "1% 100 kW (0603 Chip Resistor "1% 1.0 kW (0603 Chip Resistor "1% 432 W (0603) ...
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... A B BOTTOM VIEW 0.05 C NOTE 3 10X 0.5651 *For additional information on our Pb−Free strategy and soldering details, please download the ON Semiconductor Soldering and Mounting Techniques Reference Manual, SOLDERRM/D. NCP1835 PACKAGE DIMENSIONS DFN10 3mm, 0.5mm Pitch CASE 485C−01 ISSUE EDGE OF PACKAGE L1 ...
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... USA/Canada Japan: ON Semiconductor, Japan Customer Focus Center 2−9−1 Kamimeguro, Meguro−ku, Tokyo, Japan 153−0051 Phone: 81−3−5773−3850 http://onsemi.com 17 ON Semiconductor Website: http://onsemi.com Order Literature: http://www.onsemi.com/litorder For additional information, please contact your local Sales Representative. NCP1835/D ...