LTC4009 LTC4009-1/LTC4009-2 Typical perForMance characTerisTics (TA = 25°C unless otherwise noted. DIN = SSB44, L = IHLP-2525 6.8µH)PWM Frequency vs Charge CurrentBattery Shutdown Current 600 25 500 BAT = 5V 20 DC1104 WITH BAT = 12V SSB44 INPUT 400 DIODE 15 CLP = 15V LTC4009 300 RSENSE = 33mΩ ALL PINS RIN = 3.01k 10 200 PWM FREQUENCY (kHz) BATTERY CURRENT (µA) 5 100 BAT = 14.5V 0 0 0 0.5 1.0 1.5 2.0 2.5 3.0 0 5 10 15 20 25 CHARGE CURRENT (A) BATTERY VOLTAGE (V) 4009 G13 4009 G14 pin FuncTions CLN (Pin 1): Adapter Input Current Limit Negative Input. condition exists. An external resistor divider programs The LTC4009 senses voltage on this pin to determine if these threshold levels relative to DCIN. Operating voltage the charge current should be reduced to limit total input range is GND to INTVDD. current. The threshold is set 100mV below the CLP pin. An SHDN ( Pin 6): Active-low Shutdown Input. Driving SHDN external filter should be used to remove switching noise. below 300mV unconditionally forces the LTC4009 into the This input should be tied to CLP if not used. Operating shutdown state. This input has a 50kΩ internal pull-down voltage range is (CLP – 110mV) to CLP. to GND. Operating voltage range is GND to INTVDD. CLP (Pin 2): Adapter Input Current Limit Positive Input. ACP (Pin 7): Active-Low AC Adapter Present Indicator The LTC4009 also draws power from this pin, including Output. This open-drain output pul s to GND when adequate a small amount for some shutdown functions. Operating AC adapter (DC) voltage is present, based on the DCDIV voltage range is GND to 28V. input. This output should be left floating if not used. DCIN (Pin 3): DC Power Input. The LTC4009 draws power CHRG (Pin 8): Active-Low Charge Indicator Output. This from this pin when an external DC power source is present. open-drain output provides three levels of information This pin is typically isolated from the CLP pin by a diode about charge status using a strong pull-down, 25µA weak and should be bypassed with a capacitance of 0.1µF or pull-down or high impedance. Refer to the Operation and more. Operating voltage range is GND to 28V. Applications Information sections for further details. This ICL (Pin 4): Active-Low Input Current Limit Indicator Out- output should be left floating if not used. put. This open-drain output pulls to GND when the charge FBDIV (Pin 9, LTC4009): Battery Voltage Feedback Resis- current is reduced because of AC adapter input current tor Divider Source. The LTC4009 connects this pin to BAT limiting. This output should be left floating if not used. when charging is in progress. FBDIV is an open-drain DCDIV (Pin 5): AC Adapter Present Comparator Input. The PFET output to BAT with an operating voltage range of LTC4009 senses voltage on this pin to determine when an GND to BAT. adequate DC power source is present, or if an overvoltage 4009fd Document Outline Features Applications Description Typical Application Absolute Maximum Ratings Pin Configuration Order Information Electrical Characteristics Test Circuits Typical Performance Characteristics Pin Functions Block Diagram Operation Applications Information Package Description Revision History Typical Application Related Parts