MAX8568AETE+T Maxim Integrated Products, MAX8568AETE+T Datasheet
MAX8568AETE+T
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MAX8568AETE+T Summary of contents
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... REF THIN QFN ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. for Lithium and NiMH Batteries ♦ Automatically Manage All Backup Switchover Functions ♦ Charge Both NiMH and Rechargeable Lithium Backup Batteries ♦ ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries ABSOLUTE MAXIMUM RATINGS IN, BK, BKSU, OD1, OD2 to GND.........................-0.3V to +6.0V BKV, LDO, NI/LI to GND.........................-0. REF, CHGI, INOK, TERMV, STRTV to GND...-0. PGND to GND ......................................................-0.3V ...
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Complete Backup-Management ICs ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 3.6V INOK R5 = 250kΩ 0°C to +85°C, unless otherwise noted. Typical values are PARAMETER NI/LI Input Current OD_ ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries ELECTRICAL CHARACTERISTICS (Circuit of Figure 3.6V INOK R5 = 250kΩ -40°C to +85°C, unless otherwise noted. Typical values are PARAMETER ...
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Complete Backup-Management ICs ELECTRICAL CHARACTERISTICS (continued) (Circuit of Figure 3.6V INOK R5 = 250kΩ -40°C to +85°C, unless otherwise noted. Typical values are PARAMETER LX Current Limit (ILIM) ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries (Circuit of Figure 3.6V 1.4V CHARGE CURRENT vs. TEMPERATURE 11.0 10 3.6V 4.2V 127kΩ 10.6 10.4 ...
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Figure 3.6V MAIN-TO-BK TRANSITION WAVEFORMS MAX8658 toc13 3V V INOK 2V 2V/div MAX8568 PROVIDES 3.3V MAX1586 PROVIDES 3.3V 50mV/div V BKSU AC-COUPLED C3 = 22µF LOAD = 10mA SWITCHOVER POINT ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries PIN NAME Main Battery Input. Connect to a 2.8V to 5.5V battery or other power source. Bypass with a 4.7µ ceramic capacitor to GND. Backup Battery Input. Connect to an ...
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Complete Backup-Management ICs Detailed Description The MAX8568A/MAX8568B are compact ICs for manag- ing backup battery charging and utilization in PDAs and other smart handheld devices. The MAX8568A/ MAX8568B are comprised of three major blocks multichemistry charger for small ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries BK CHARGER IN 2.43V INOK I/O IN I/O OUT STEP-UP DC-DC CONVERTER OD1 MEM IN MEM OUT LDO OD2 Figure 1. Timing Diagram Applications Information Setting the Charge Current Charge current is ...
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Complete Backup-Management ICs The lithium charger acts like a current-limited voltage source. The battery regulation voltage for lithium mode is: BK(LIMAX 3 BK(LIMAX 1.2V, then the final charge voltage is 4.2V. ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries Note that both V and V BK(NILO) BK(NIHI) 2-resistor voltage-divider as shown in the typical applica- tion circuit (see Figure 7) if the factory-set ratio between the two thresholds is acceptable. In ...
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Complete Backup-Management ICs The control scheme of the MAX8568 permits flexibility in choosing an inductor. A 10µH inductor performs well in most applications. Smaller inductance values typically offer smaller physical size for a given series resistance, allowing the smallest overall ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries Pullup resistors, R3 and R4 in Figure 7, should be select ensure that when OD1 and OD2 go high imped- ance, the gate of the external MOSFET discharges within 50µs ...
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Complete Backup-Management ICs REF REF GND IN BK UVLO LI 1.13 LX BKSU PGND BKV OD1 LDO OD2 Figure 6. Functional Diagram ______________________________________________________________________________________ for Lithium and NiMH Batteries MAX8568 BK CHARGE CURRENT SOURCE 0.67 1 0.86 NI STEP-UP CONVERTER UVLO ...
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Complete Backup-Management ICs for Lithium and NiMH Batteries MAIN BATTERY 2.8V TO 5.5V BACKUP BATTERY 10µH I/O OUT 3.3V, 50mA OPEN I 0Ω R3 100kΩ MEM OUT 2.5V, 10mA MEM 100kΩ Figure 7. Typical Application ...
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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. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17 © 2005 Maxim Integrated Products ...