ISL6256 INTERSIL [Intersil Corporation], ISL6256 Datasheet
ISL6256
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ISL6256 Summary of contents
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... Ld 5x5 QFN L28.5x5 ISL6256HAZ ISL 6256HAZ -10 to +100 28 Ld QSOP ISL6256AHRZ ISL6256 AHRZ -10 to +100 28 Ld 5x5 QFN L28.5x5 ISL6256AHAZ ISL6256 AHAZ -10 to +100 28 Ld QSOP NOTES: 1. Add “-T” suffix for tape and reel. Please refer to TB347 for details on reel specifications ...
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... VREF 6 CHLIM ISL6256, ISL6256A CSOP 20 CSIN 19 CSIP 18 SGATE 17 BGATE 16 PHASE UGATE ISL6256, ISL6256A (28 LD QSOP) TOP VIEW 1 28 DCPRN DCIN 2 27 ACPRN VDD 3 26 CSON ACSET 4 25 CSOP DCSET 5 24 CSIN CSIP CELLS 7 22 SGATE ...
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... 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 ISL6256, ISL6256A SGATE ICM CSIP CSIN - + X19.9 CA1 + 1.26V CSON - gm3 + + MIN CURRENT BUFFER 300kHz - RAMP PWM Σ ...
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... TRICKLE CHARGE CHLIM CHLIM CHLIM CHLIM R13 R13 R11 R11 1.87k 130k TRICKLE Q6 CHARGE FIGURE 2. ISL6256, ISL6256A TYPICAL APPLICATION CIRCUIT WITH FIXED CHARGING PARAMETERS 4 ISL6256, ISL6256A SGATE SGATE SGATE SGATE 2.2Ω R21 CSIP CSIP CSIP CSIP ...
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... AVDD/VREF 4.7k SCL SCL SCL SDL SDL SDL A/D INPUT A/D INPUT A/D INPUT GND GND GND GND FIGURE 3. ISL6256, ISL6256A TYPICAL APPLICATION CIRCUIT WITH µP CONTROL AND AIRCRAFT POWER SUPPORT 5 ISL6256, ISL6256A 0.1 0.1 0.1 0.1µ DCIN DCIN DCIN SGATE SGATE ...
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... Reference Output Voltage VREF Battery Charge Voltage Accuracy TRIP POINTS ACSET Threshold ACSET Input Bias Current Hysteresis 6 ISL6256, ISL6256A 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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... Voltage ISL6256A CSOP to CSON Full-Scale Current Sense Voltage ISL6256 CSOP to CSON Full-Scale Current Sense Voltage Formula ISL6256A CSOP to CSON Full-Scale Current Sense Voltage Formula CHLIM Input Bias Current 7 ISL6256, ISL6256A ≤ +125°C, Unless Otherwise Noted. Boldface limits apply over the ...
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... SGATE Pull-up Current SGATE Pull-down Current CSIP-SGATE Voltage High CSIP-SGATE Voltage Low CSIP-CSIN Threshold for CSIP-SGATE Going High 8 ISL6256, ISL6256A ≤ +125°C, Unless Otherwise Noted. Boldface limits apply over the J TEST CONDITIONS CHLIM rising CSIP = CSIN = 25V 0 < CSIN < DCIN ...
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... 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. 9 ISL6256, ISL6256A ≤ +125°C, Unless Otherwise Noted. Boldface limits apply over the J TEST CONDITIONS ...
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... CSIP-CSIN (mV) FIGURE 6. ACCURACY vs AC ADAPTER CURRENT FIGURE 8. AC AND DC ADAPTER DETECTION 10 ISL6256, ISL6256A DCIN = 20V, 4S2P Li-Battery, T 0.10 0.08 0.06 0.04 0.02 0. 100 FIGURE 7. SYSTEM EFFICIENCY vs CHARGE CURRENT DCIN DCIN 10V/div 10V/div ACSET 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 11 ISL6256, ISL6256A 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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... CSIP/CSIN CSIP/CSIN is the AC adapter current sensing positive/negative input. The differential voltage across CSIP and CSIN is used to sense the AC adapter current, and is 12 ISL6256, ISL6256A DCIN = 20V, 4S2P Li-Battery FIGURE 16. TRICKLE TO FULL-SCALE CHARGING compared with the AC adapter current limit to regulate the AC adapter current ...
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... The charger also drives an adapter isolation P-Channel MOSFET to efficiently switch in the adapter supply. ISL6256 is a complete power source selection controller for single battery systems and also aircraft power applications. It drives a battery selector P-Channel MOSFET to efficiently select between a single battery and the adapter ...
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... Schottky diode is between the VDDP pin and BOOT pin to keep the bootstrap capacitor charged. Setting the Battery Regulation Voltage The ISL6256 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 ...
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... ISL6256, ISL6256A capability of the AC adapter can be lowered, reducing system cost. The ISL6256 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 constant input current regulation allows the adapter to fully power the system and prevent the AC adapter from overloading and crashing the system bus ...
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... The ICM, ACPRN and DCPRN outputs continue to function. (EQ. 12) EN can be driven by a thermistor to allow automatic shutdown of the ISL6256 when the battery pack is hot. Often (EQ. 13) 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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... Overvoltage Protection ISL6256 has an Overvoltage Protection circuit that limits the output voltage when the battery is removed or disconnected by a pulse charging circuit. If CSON exceeds the output voltage set point by more than V OVP pulls VCOMP down and turns off both upper and lower FETs of the buck as in Figure 17 ...
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... AC adapter output voltage, which is relatively constant. The maximum efficiency is 18 ISL6256, ISL6256A achieved by selecting a high side MOSFET that has the conduction losses equal to the switching losses. Switching losses in the low-side FET are very small. The choice of (EQ ...
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... Substituting I = 24mA and f GATE into Equation 27 yields that the total gate charge should be less than 80nC. Therefore, the ISL6256 easily drives the battery charge current up to 10A. Snubber Design ISL6256'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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... LOOP COMPENSATION DESIGN ISL6256 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 charging and the third limits current drawn from the adapter. ...
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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, ISL6256 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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... information is added to the feedback to create a second zero f ZERO2 R BAT ISL6256 add a pole resistors that set the DC output voltage. For a 3-cell battery, R ESR R = 320kΩ and relate the compensation network’s poles, zeros and gain to the components in Figure 22. Figure 2424 shows an asymptotic bode plot of the DC/DC converter’ ...
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... VCOMP 0.3 F 2π VCOMP 23 ISL6256, ISL6256A PCB Layout Considerations f LC Power and Signal Layers Placement on the PCB f POLE1 As a general rule, power layers should be close together, either on the top or bottom of the board, with signal layers on the opposite side of the board example, layer arrangement on a 4-layer board is shown below: 1 ...
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... KELVIN CONNECTION TRACES TO THE LOW PASS FILTER AND CSOP AND CSON FIGURE 25. CURRENT SENSE RESISTOR LAYOUT 24 ISL6256, ISL6256A EN Pin This pin stays high at enable mode and low at idle mode and is relatively robust. Enable signals should refer to the signal ground. DCIN Pin This pin connects to AC adapter output voltage, and should be less noise sensitive ...
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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 25 ISL6256, ISL6256A 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 26 ISL6256, ISL6256A M28.15 28 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE M ...