MAX8731AETI+ Maxim Integrated Products, MAX8731AETI+ Datasheet

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... Battery Voltage Setting ♦ 6-Bit Charge-Current/Input-Current Setting ♦ 8A (max) Battery Charger Current ♦ 11A (max) Input Current ♦ +8V to +26V Input Voltage Range ♦ Charges Li+, NiMH, and NiCd Battery Chemistries PART MAX8731AETI+ Applications +Indicates a lead-free package. OPTIONAL 15 14 BATSEL ...

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SMBus Level 2 Battery Charger with Remote Sense ABSOLUTE MAXIMUM RATINGS DCIN, CSSN, CSIN, FBSA, FBSB to GND..............-0.3V to +28V CSSP to CSSN, CSIP to CSIN, PGND to GND ......-0.3V to +0.3V BST to GND ............................................................-0.3V to +32V BST to ...

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SMBus Level 2 Battery Charger ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure 0°C ...

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SMBus Level 2 Battery Charger with Remote Sense ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure 1; ...

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SMBus Level 2 Battery Charger ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure 0°C ...

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SMBus Level 2 Battery Charger with Remote Sense ELECTRICAL CHARACTERISTICS ( 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure 1; T ...

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SMBus Level 2 Battery Charger ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure -40°C ...

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SMBus Level 2 Battery Charger with Remote Sense ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF Figure 1; ...

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SMBus Level 2 Battery Charger ELECTRICAL CHARACTERISTICS (continued 19V, V DCIN LX CSSP CSSN C = 1µ LDO 1µF, C LDO CC REF per Figure ...

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SMBus Level 2 Battery Charger with Remote Sense (Circuit of Figure 1, adapter = 19.5V, ChargeVoltage() = 16.8V, ChargeCurrent() = 3.854A, InputCurrent() = 3.584A, T unless otherwise noted.) INPUT CURRENT-LIMIT ERROR vs. INPUT CURRENT-LIMIT SETTING 6 4 MAXIMUM 2 TYPICAL ...

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SMBus Level 2 Battery Charger (Circuit of Figure 1, adapter = 19.5V, ChargeVoltage() = 16.8V, ChargeCurrent() = 3.854A, InputCurrent() = 3.584A, T unless otherwise noted.) CHARGE-VOLTAGE ERROR vs. CHARGE-VOLTAGE SETTING 0.6 0.4 0.2 0.0 -0.2 -0.4 -0 CHARGE-VOLTAGE ...

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SMBus Level 2 Battery Charger with Remote Sense (Circuit of Figure 1, adapter = 19.5V, ChargeVoltage() = 16.8V, ChargeCurrent() = 3.854A, InputCurrent() = 3.584A, T unless otherwise noted.) LDO LINE REGULATION NOT SWITCHING -5 -6 ...

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SMBus Level 2 Battery Charger PIN NAME 1, 12 GND Analog Ground. Connect directly to the paddle. 2 ACIN AC Adapter Detect Input. ACIN is the input to an uncommitted comparator. 3 REF 4.096V Voltage Reference. Bypass REF with a ...

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SMBus Level 2 Battery Charger with Remote Sense ADAPTER INPUT R1 150kΩ 1μF R3 49.9kΩ LDO INPUT VDD R5 10kΩ KBC SCL SDA R8 10kΩ C4 0.01μF Figure 1. Typical Dual-Battery Application Circuit Detailed Description The typical application ...

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SMBus Level 2 Battery Charger command. The charge current-regulation loop is in con- trol as long as the selected battery voltage is below the charge voltage set point. When the selected battery voltage reaches its set point, the voltage-regulation loop ...

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SMBus Level 2 Battery Charger with Remote Sense Setting Charge Voltage To set the output voltage, use the SMBus to write a 16-bit ChargeVoltage() command using the data format listed in Table 1. The ChargeVoltage() command uses the Write- Word ...

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SMBus Level 2 Battery Charger Setting Charge Current To set the charge current, use the SMBus to write a 16- bit ChargeCurrent() command using the data format listed in Table 2. The ChargeCurrent() command uses the Write-Word protocol (see Figure ...

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SMBus Level 2 Battery Charger with Remote Sense ( ⎡ × I CHARGE = + ⎢ INPUT LOAD ⎢ V ⎣ IN where η is the efficiency of the DC-DC converter (typi- cally 85% to 95%). To ...

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SMBus Level 2 Battery Charger where R is the total resistance in the battery pack, Pack R is the board resistance in series with the battery Board charge path the constant-voltage charge time CV0 without remote sense, and ...

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SMBus Level 2 Battery Charger with Remote Sense SMBus Interface The MAX8731A receives control inputs from the SMBus interface. The MAX8731A uses a simplified subset of the commands documented in System Management Bus Specification V1.1, which can be downloaded from ...

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SMBus Level 2 Battery Charger LOW HIGH SMBCLK SMBDATA t t SU:STA HD:STA A = START CONDITION B = MSB OF ADDRESS CLOCKED INTO SLAVE C = LSB OF ADDRESS CLOCKED INTO SLAVE D = R/W ...

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SMBus Level 2 Battery Charger with Remote Sense Table 4. Battery-Charger Command Summary COMMAND COMMAND NAME 0x14 ChargeCurrent() 0x15 ChargeVoltage() 0x3F InputCurrent() 0xFE ManufacturerID() 0xFF DeviceID() Battery-Charger Commands The MAX8731A supports four battery-charger com- mands that use either Write-Word or ...

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SMBus Level 2 Battery Charger control point. Clamping the other two control loops close to the lowest control loop ensures fast transition with minimal overshoot when switching between differ- ent control loops (see the Compensation section). Continuous-Conduction Mode With sufficient ...

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SMBus Level 2 Battery Charger with Remote Sense The charge-voltage and charge-current regulation loops are independent and compensated separately at the CCV, CCI, and CCS. CCV Loop Compensation The simplified schematic in Figure 7 describe the operation of the MAX8731A ...

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SMBus Level 2 Battery Charger C is also much lower impedance than R OUT crossover so the parallel impedance is mostly capaci- tive and: ⋅ ≅ + × OUT ...

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SMBus Level 2 Battery Charger with Remote Sense The loop-transfer function is given by: = × × × LTF GMI OUT CSI This describes a single-pole system. Since OUT × CSI ...

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SMBus Level 2 Battery Charger The crossover frequency is given by: GMS = 2π For stability, choose a crossover frequency lower than 1/10 the switching frequency: = × π GMS /( 2 ...

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SMBus Level 2 Battery Charger with Remote Sense where t is the driver’s transition time and can be TRANS calculated as follows: ⎛ ⎞ ⎟ × t ⎜ , TRANS ⎝ ⎠ I ...

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SMBus Level 2 Battery Charger Input-Capacitor Selection The input capacitor must meet the ripple current requirement (I ) imposed by the switching currents. RMS Nontantalum chemistries (ceramic, aluminum, or OS-CON) are preferred due to their resilience to power- up surge ...

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SMBus Level 2 Battery Charger with Remote Sense Good PCB layout is required to achieve specified noise immunity, efficiency, and stable performance. The PCB layout artist must be given explicit instructions—prefer- ably, a sketch showing the placement of the power- ...

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SMBus Level 2 Battery Charger (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages.) ______________________________________________________________________________________ with Remote Sense Package Information PACKAGE OUTLINE, 16, 20, 28, 32, ...

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... Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. 32 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2007 Maxim Integrated Products Package Information (continued) PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0 ...