LTC4007EGN Linear Technology, LTC4007EGN Datasheet
LTC4007EGN
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LTC4007EGN Summary of contents
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... L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear Technology Corporation. All other trademarks are the property of their respective owners. ...
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... UVLO Undervoltage Lockout Threshold Shutdown Threshold at SHDN SHDN Pin Current Operating Current in Shutdown 2 PIN CONFIGURATION PART MARKING PACKAGE DESCRIPTION LTC4007EGN 24-Lead Plastic SSOP http://www.linear.com/leadfree/ http://www.linear.com/tapeandreel/ The l denotes the specifi cations which apply over the full operating = 25° 20V, V ...
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ELECTRICAL CHARACTERISTICS temperature range (Note 4), otherwise specifi cations are at T SYMBOL PARAMETER Current Sense Amplifi er, CA1 Input Bias Current Into BAT Pin CMSL CA1/I Input Common Mode Low 1 CMSH CA1/I Input Common Mode High 1 Current ...
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LTC4007 ELECTRICAL CHARACTERISTICS temperature range (Note 4), otherwise specifi cations are at T SYMBOL PARAMETER Low Logic Level of ACP , CHG, FLAG, LOBAT FAULT I CL High Logic Level of CHG, LOBAT ...
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TYPICAL PERFORMANCE CHARACTERISTICS INFET Response Time to Reverse Current V OF PFET (2V/DIV PFET (5V/DIV (REVERSE PFET (5A/DIV 1.25μs/DIV TEST PERFORMED ...
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LTC4007 TYPICAL PERFORMANCE CHARACTERISTICS Effi ciency at 19VDC V 100 0.50 1.00 CHARGE CURRENT (A) PIN FUNCTIONS DCIN (Pin 1): External DC Power Source Input. Bypass this pin with at least 0.01μF. See Applications Information. ...
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PIN FUNCTIONS ITH (Pin 10): Control Signal of the Inner Loop of the Current Mode PWM. Higher ITH voltage corresponds to higher charging current in normal operation resistor, in series with a capacitor of at least 0.1μF to ...
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LTC4007 BLOCK DIAGRAM 0.1μ DCIN 1 5.8V INFET Q3 23 ACP 3 SHDN 24 FAULT 5 FLAG 17 GND 6 3C4C 7 CHEM 16 + LOBAT 8 – 708mV 1.19V 5k CLP Ω – 1.4m 18 ...
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TEST CIRCUIT OPERATION Overview The LTC4007 is a synchronous current mode PWM step- down (buck) switcher battery charger controller. The charge current is programmed by the combination of a program resistor (R ) from the PROG pin to ground and ...
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LTC4007 OPERATION Table 1. Truth Table For Indicator States MODE Shut down by low adapter voltage Charging a low bat Normal charging Input current limited charging Charger paused due to thermistor out of range Shut down by SHDN pin Terminated ...
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OPERATION The peak inductor current, at which I latch, is controlled by the voltage on ITH. ITH is in turn controlled by several loops, depending upon the situation at hand. The average current control loop converts the voltage between CSP ...
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LTC4007 OPERATION by the timing resistor connected to R closed to sample the thermistor 127.5 • 20 • R • 17.5pF = 13.8ms, SAMPLE RT for R = 309k RT The external RC network is driven to approximately ...
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APPLICATIONS INFORMATION Battery Detection It is generally not good practice to connect a battery while the charger is running. The timer unknown state and the charger could provide a large surge current into the battery for a ...
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LTC4007 APPLICATIONS INFORMATION amount as the full-scale voltage is reduced then 2.49k and R = 26.7k, the maximum charging PROG current is still 2.5A but the FLAG trip point is maintained at 10% of full scale. ...
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APPLICATIONS INFORMATION be used when tantalum capacitors are used for input or output bypass. High input surge currents can be created when the adapter is hot-plugged to the charger or when a battery is connected to the charger. Solid tantalum ...
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LTC4007 APPLICATIONS INFORMATION Charger Switching Power MOSFET and Diode Selection Two external power MOSFETs must be selected for use with the charger: a P-channel MOSFET for the top (main) switch and an N-channel MOSFET for the bottom (syn- chronous) switch. ...
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APPLICATIONS INFORMATION Adapter Limiting An important feature of the LTC4007 is the ability to auto- matically adjust charging current to a level which avoids overloading the wall adapter. This allows the product to operate at the same time that batteries ...
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LTC4007 APPLICATIONS INFORMATION LTC4007 R9 NTC 9 C7 R9A Figure 10. General Thermistor Network If you are using a thermistor that doesn’t have a 1:7 HIGH/LOW ratio, or you wish to set the HIGH/LOW limits to different temperatures, then the ...
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APPLICATIONS INFORMATION Disabling the Thermistor Function If the thermistor is not needed, connecting a resistor be- tween DCIN and NTC will disable it. The resistor should be sized to provide at least 10μA with the minimum voltage applied to DCIN ...
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LTC4007 APPLICATIONS INFORMATION General Rules 7. Connection of switching ground to system ground or internal ground plane should be single point. If the system has an internal system ground plane, a good way to do this is to cluster vias ...
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APPLICATIONS INFORMATION DCIN 0V TO 20V 3A 3C4C V * LOGIC R10 R11 R12 CHEM * 100k 100k 100k LOBAT LOBAT ACP ACP SHDN SHDN FAULT FAULT CHG CHG FLAG FLAG R9 32.4k 1% NTC R ...
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LTC4007 APPLICATIONS INFORMATION SWITCH NODE HIGH FREQUENCY CIRCULATING PATH Figure 12. High Speed Switching Path PACKAGE DESCRIPTION .254 MIN .0165 .0015 RECOMMENDED SOLDER PAD LAYOUT .0075 – .0098 (0.19 – 0.25) .016 – .050 (0.406 – 1.270) ...
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... Termination” text added Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representa- tion that the interconnection of its circuits as described herein will not infringe on existing patent rights. LTC4007 ...
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... VID LTC4006 Small, High Effi ciency, Fixed Voltage, Lithium-Ion Battery Charger LTC4008 High Effi ciency, Programmable Voltage/Current Battery Charger trademark of Linear Technology Corporation. SENSE Linear Technology Corporation 24 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408) 432-1900 FAX: (408) 434-0507 ● 12.6V/4A Li-Ion Battery Charger ...