ISL6252 INTERSIL [Intersil Corporation], ISL6252 Datasheet
ISL6252
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ISL6252 Summary of contents
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... Data Sheet Highly Integrated Battery Charger Controller for Notebook Computers The ISL6252, ISL6252A is a highly integrated battery charger controller for Li-ion/Li-ion polymer batteries. High Efficiency is achieved by a synchronous buck topology. The low side MOSFET emulates a diode at light loads to improve the light load efficiency and prevent system bus boosting ...
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... VREF 7 CHLIM ISL6252, ISL6252A CSOP 20 CSIN 19 CSIP PHASE 16 15 UGATE 13 14 ISL6252, ISL6252A (24 LD QSOP) TOP VIEW VDD DCIN 1 24 ACSET 2 23 ACPRN EN CSON 3 22 CELLS 4 21 CSOP ICOMP 5 20 CSIN VCOMP CSIP 6 19 ICM ...
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... ISL6252, ISL6252A ACSET ACPRN + - 1.26V VREF 152kΩ ADAPTER CURRENT ACLIM LIMIT SET 152kΩ ICOMP MIN VOLTAGE BUFFER VCOMP VREF 514kΩ gm1 VADJ - 514kΩ 2.1V VOLTAGE CELLS SELECTOR VDD REFERENCE VREF GND FB FIGURE 1. FUNCTIONAL BLOCK DIAGRAM 3 ICM CSIP CSIN ...
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... TRICKLE CHARGE CHLIM CHLIM CHLIM CHLIM R13 R13 R11 R11 1.87k 130k 1% 1% TRICKLE Q6 CHARGE FIGURE 2. ISL6252, ISL6252A TYPICAL APPLICATION CIRCUIT WITH FIXED CHARGING PARAMETERS 4 ISL6252, ISL6252A D4 D3 R21 2.2Ω CSIP CSIP CSIP CSIP ISL6252 ISL6252 ISL6252 ISL6252 0.1µ ...
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... INPUT HOST CURRENT LIMIT C6 C6 6.8nF R11, R12 R13: 10k AVDD/VREF 4.7k 10nF SCL SDL A/D INPUT GND FIGURE 3. ISL6252, ISL6252A TYPICAL APPLICATION CIRCUIT WITH µP CONTROL 5 ISL6252, ISL6252A D4 D3 DCIN DCIN DCIN R21 2.2Ω CSIP CSIP CSIP ACSET ACSET ACSET C2 C2 0.1µ ...
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... TRIP POINTS ACSET Threshold ACSET Input Bias Current Hysteresis ACSET Input Bias Current ACSET Input Bias Current 6 ISL6252, ISL6252A Thermal Information Thermal Resistance QFN Package (Notes 5, 6 QSOP Package (Note Junction Temperature Range .-10°C to +150°C Operating Temperature Range . . . . . . . . . . . . . . . .-10°C to +100°C Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65° ...
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... CSOP to CSON Full-Scale Current Sense Voltage ISL6252A CSOP to CSON Full-Scale Current Sense Voltage ISL6252 CSOP to CSON Full-Scale Current Sense Voltage Formula ISL6252A CSOP to CSON Full-Scale Current Sense Voltage Formula CHLIM Input Bias Current CHLIM Power-down Mode Threshold Voltage CHLIM Power-down Mode Hysteresis Voltage ...
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... This is the sum of currents in these pins (CSIP, CSIN, BOOT, UGATE, PHASE, CSOP, CSON) all tied to 16.8V. No current in pins EN, ACSET, VADJ, CELLS, ACLIM, CHLIM. 8. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified. Temperature limits are established by characterization and are not production tested. 8 ISL6252, ISL6252A TEST CONDITIONS ACLIM = VREF ACLIM = Float ACLIM = GND ...
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... CSIP-CSIN (mV) FIGURE 6. ACCURACY vs AC ADAPTER CURRENT FIGURE 8. AC AND DC ADAPTER DETECTION 9 ISL6252, ISL6252A DCIN = 20V, 4S2P Li-Battery, T 0.10 0.08 0.06 0.04 0.02 0. 100 100 FIGURE 7. SYSTEM EFFICIENCY vs CHARGE CURRENT DCIN DCIN 10V/div 10V/div ACSET ...
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... CHLIM = 0.2V CHLIM=0.2V CHLIM=0.2V CSON = 8V CSON=8V CSON=8V FIGURE 12. SWITCHING WAVEFORMS AT DIODE EMULATION ADAPTER REMOVAL ADAPTER REMOVAL ADAPTER REMOVAL FIGURE 14. AC ADAPTER REMOVAL 10 ISL6252, ISL6252A DCIN = 20V, 4S2P Li-Battery +25°C, Unless Otherwise Noted. (Continued) A CSON CSON 5V/div 5V/div EN EN 5V/div 5V/div INDUCTOR ...
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... GND is an analog ground. DCIN The DCIN pin is the input of the internal 5V LDO. Connect it to the AC adapter output. Connect a 0.1µF ceramic capacitor from DCIN to CSON. 11 ISL6252, ISL6252A DCIN = 20V, 4S2P Li-Battery +25°C, Unless Otherwise Noted. (Continued) A FIGURE 16. TRICKLE TO FULL-SCALE CHARGING ACSET ACSET adapter detection input ...
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... Li-ion and Li-polymer batteries. A high efficiency synchronous buck converter is used to control the charging voltage and charging current up to 10A. The ISL6252 has input current limiting and analog inputs for setting the charge current and charge voltage; CHLIM inputs are used to control charge current and VADJ inputs are used to control charge voltage ...
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... Setting the Battery Regulation Voltage The ISL6252 uses a high-accuracy trimmed band-gap voltage reference to regulate the battery charging voltage. The VADJ input adjusts the charger output voltage, and the VADJ control voltage can vary from 0 to VREF, providing a 10% adjustment range (from 4. 4.2V + 5%) on CSON regulation voltage ...
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... By using the input current limiter, the current capability of the AC adapter can be lowered, reducing system cost. The ISL6252 limits the battery charge current when the input current-limit threshold is exceeded, ensuring the battery charger does not load down the AC adapter voltage. This ...
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... VCOMP and ICOMP are pulled to ground. The ICM, ACPRN output continue to function. EN can be driven by a thermistor to allow automatic shutdown of the ISL6252 when the battery pack is hot. Often a NTC thermistor is included inside the battery pack to measure its temperature. When connected to the charger, the thermistor forms a voltage divider with a resistive pull-up to the VREF ...
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... CO 2π L Output Capacitor Selection The output capacitor in parallel with the battery is used to absorb the high frequency switching ripple current and 16 ISL6252, ISL6252A smooth the output voltage. The RMS value of the output ripple current RMS where the duty cycle D is the ratio of the output voltage ...
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... Substituting I into Equation 25 yields that the total gate charge should be less than 80nC. Therefore, the ISL6252 easily drives the battery charge current up to 10A. Snubber Design ISL6252's buck regulator operates in discontinuous current mode (DCM) when the load current is less than half the peak-to-peak current in the inductor ...
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... R 1.87kΩ, ±1%, (0805) 13 Loop Compensation Design ISL6252 has three closed loop control modes. One controls the output voltage when the battery is fully charged or absent. A second controls the current into the battery when (EQ. 28) charging and the third limits current drawn from the adapter. ...
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... C CHLIM + ICOMP - FIGURE 19. CHARGE CURRENT LIMIT LOOP 19 ISL6252, ISL6252A The compensation capacitor (C amplifier (GMI) a pole at a very low frequency (<<1Hz) and a a zero at f ICOMP. The frequency of can be calculated from L Equation 31: f ZERO CO Placing this zero at a frequency equal to the pole calculated in Equation 29 will result in maximum gain at low frequencies and phase margin near 90° ...
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... If the combined battery charge current and system load current draws current that equals the adapter current limit set by the ACLIM pin, ISL6252 will reduce the current to the battery and/or reduce the output voltage to hold the adapter current at the limit. Above the adapter current limit, the minimum current buffer equals the output of gm3 and ICOMP controls the charger output ...
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... Inductor current ZERO1 information is added to the feedback to create a second zero The low pass filter ZERO2 F2 and ISL6252 add a pole FILTER divider resistors that set the DC output voltage. For a 3-cell battery 320kΩ and R = 64kΩ. Equations 37, 38, 39 40, 41 and 42 relate the compensation network’ ...
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... IC. The best tie-point between the signal ground and the power ground is at the negative side of the output capacitor on each side, where there is little noise; a noisy trace beneath the IC is not recommended. 22 ISL6252, ISL6252A GND and VDD Pin At least one high quality ceramic decoupling capacitor R 4 should be used to cross these two pins. The decoupling 48kΩ ...
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... Clamping Capacitor for Switching MOSFET It is recommended that ceramic capacitors be used closely connected to the drain of the high-side MOSFET, and the source of the low-side MOSFET. This capacitor reduces the noise and the power loss of the MOSFET. 23 ISL6252, ISL6252A HIGH CURRENT TRACE FN6498.3 August 25, 2010 ...
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... L28.5x5 28 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE Rev 2, 10/07 5.00 6 PIN 1 INDEX AREA (4X) 0.15 TOP VIEW ( 4. 65 TYP ) ( 3. 10) TYPICAL RECOMMENDED LAND PATTERN 24 ISL6252, ISL6252A 28X 0.55 ± 0. ± 0.1 ( 24X 0 . 50) (28X 28X 0 . 75) NOTES: 1. Dimensions are in millimeters. Dimensions ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 25 ISL6252, ISL6252A M24.15 24 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE M ...