MAX8724ETI+ Maxim Integrated Products, MAX8724ETI+ Datasheet
MAX8724ETI+
Specifications of MAX8724ETI+
Related parts for MAX8724ETI+
MAX8724ETI+ Summary of contents
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... AC Adapter Presence 17.6V Battery-Voltage Set Point o Maximum 28V Input Voltage o > 95% Efficiency o Shutdown Control Input o Charge Any Battery Chemistry Li+, NiCd, NiMH, Lead Acid, etc. PART MAX1908ETI+ Applications MAX8724ETI+ MAX8765ETI+ MAX8765AETI+ + Denotes a lead(Pb)-free/RoHS-compliant package Exposed pad. TO EXTERNAL LOAD TOP VIEW DLOV LX ...
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Low-Cost Multichemistry Battery Chargers ABSOLUTE MAXIMUM RATINGS DCIN, CSSP, CSSN, ACOK to GND.......................-0.3V to +30V BST to GND ............................................................-0.3V to +36V BST to LX..................................................................-0.3V to +6V DHI to LX ...................................................-0. GND .................................................................-6V to +30V BATT, CSIP, ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS ( 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a -40°C ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers ELECTRICAL CHARACTERISTICS (continued 18V, V DCIN CSSP CSSN BATT REF 4.5V, ACIN = GND = PGND = 0, C BST LX per Figure 1a ...
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Low-Cost Multichemistry Battery Chargers (Circuit of Figure 20V +25°C, unless otherwise noted.) DCIN A LINE-TRANSIENT RESPONSE MAX1908 toc04 V DCIN 10V/div V BATT 500mV/div INDUCTOR CURRENT 500mA/div 10ms/div ICTL = LDO VCTL = LDO I ...
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Low-Cost Multichemistry Battery Chargers (Circuit of Figure 20V +25°C, unless otherwise noted.) DCIN A CURRENT-SETTING ERROR vs. ICTL 3.3V REFIN 0.5 1.0 V (V) ICTL ...
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Low-Cost Multichemistry Battery Chargers PIN NAME 1 DCIN Charging Voltage Input. Bypass DCIN with a 1µF capacitor to PGND. 2 LDO D evi Outp ut of the 5. near ...
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Low-Cost Multichemistry Battery Chargers Detailed Description The MAX1908/MAX8724/MAX8765/MAX8765A include all the functions necessary to charge Li+ batteries. A high-efficiency synchronous-rectified step-down DC-DC converter controls charging voltage and current. The device also includes input-source current limiting and analog inputs for setting ...
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Low-Cost Multichemistry Battery Chargers AC ADAPTER INPUT 8.5V TO 28V R6 R7 59kΩ 19.6kΩ DAC OUTPUT 12.6V OUTPUT VOLTAGE 1MΩ OUTPUT ADC INPUT ADC INPUT C14 R9 C20 0.1µF 0.1µF 20kΩ HOST 0.01µF AVDD/REF R19, ...
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Low-Cost Multichemistry Battery Chargers AC ADAPTER INPUT 8.5V TO 28V R6 D2 59kΩ LDO 19.6kΩ 1µF R14 10.5kΩ 1% R15 8.25kΩ 1% 16.8V OUTPUT VOLTAGE R16 2.5A CHARGE LIMIT 8.25kΩ 1% R19 10kΩ FROM HOST µP ...
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Low-Cost Multichemistry Battery Chargers SHDN 23.5% REFIN GND GND DCIN CCS 75mV x CLS REF CSSP LEVEL SHIFTER CSSN CSIP LEVEL SHIFTER CSIN 75mV x ICTL REFIN CCI 3.1V/CELL BATT R1 REFIN CELL SELECT CELLS LOGIC CCV 400mV x VCTL ...
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Low-Cost Multichemistry Battery Chargers Setting the Charging-Current Limit The ICTL input sets the maximum charging current. The current is set by current-sense resistor RS2, connected between CSIP and CSIN. The full-scale differential voltage between CSIP and CSIN is 75mV; thus, ...
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Low-Cost Multichemistry Battery Chargers /2. Since ACOK can withstand 30V (max), ACOK V REF can drive a p-channel MOSFET directly at the charger input, providing a lower dropout voltage than a Schottky diode (Figure 2). In the MAX1908/MAX8724 the ACOK ...
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Low-Cost Multichemistry Battery Chargers RESET IMAX 1.8V CCMP IMIN 0.15V ZCMP 0.1V CONTROL CCS CCI CCV Figure 4. DC-DC Functional Diagram 20 ______________________________________________________________________________________ 5ms S MAX1908 BST MAX8724 R Q MAX8765 MAX8765A R Q CHG OFF GENERATOR ...
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Low-Cost Multichemistry Battery Chargers In normal operation, the controller starts a new cycle by turning on the high-side n-channel MOSFET and turning off the low-side n-channel MOSFET. When the charge current is greater than the control point (LVC), CCMP goes ...
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Low-Cost Multichemistry Battery Chargers GM OUT CCV GMV OGMV REF C CV Figure 5. CCV Loop Diagram CCV Loop Definitions Compensation of the CCV loop depends on the para- meters and components shown in Figure 5. C ...
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Low-Cost Multichemistry Battery Chargers The 22µF ceramic capacitor has a typical ESR of 0.003Ω, which sets the output zero at 2.412MHz. The output pole is set at OUT _ π × OUT ...
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Low-Cost Multichemistry Battery Chargers CSIP GM OUT CCI GMI R C OGMI CI ICTL Figure 7. CCI Loop Diagram The crossover frequency is given by: GMI = 2π The CCI loop dominant compensation pole: ...
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Low-Cost Multichemistry Battery Chargers the charge-current amplifier transconductance = 1µA/mV the DC-DC converter transconductance = IN 3.3A/V. The CCS loop is a single-pole system with a dom- inant pole compensation set by f P_CS ...
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Low-Cost Multichemistry Battery Chargers Choose crossover frequency f CO_CS MAX1908/MAX8724/MAX8765/MAX8765A switching frequency: GMS = = π Solving for 2nF conservative, set C = 10nF, which ...
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Low-Cost Multichemistry Battery Chargers where dV is the maximum voltage sag of 0.5V while delivering energy to the inductor during the high-side MOSFET on-time, and dt is the period at highest oper- ating frequency (400kHz): µ ...
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... R19, R20 2 10kΩ ±1% resistors (0603) 0.01Ω ±1%, 0.5W 2010 sense resistor RS1 1 Vishay Dale WSL2010 0.010 1.0% IRC LRC-LR2010-01-R010-F 0.015Ω ±1%, 0.5W 2010 sense resistor RS2 1 Vishay Dale WSL2010 0.015 1.0% IRC LRC-LR2010-01-R015-F MAX1908ETI+, MAX8724ETI MAX8765ETI+, MAX8765AETI+ ...
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Low-Cost Multichemistry Battery Chargers Chip Information TRANSISTOR COUNT: 3772 PROCESS: BiCMOS ______________________________________________________________________________________ Package Information For the latest package outline information and land patterns www.maxim-ic.com/packages. Note that a "+", "#", or "-" in the package code indicates RoHS status ...
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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. 30 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2009 Maxim Integrated Products DESCRIPTION Maxim is a registered trademark of Maxim Integrated Products, Inc ...