MAX1538ETI+T Maxim Integrated Products, MAX1538ETI+T Datasheet
MAX1538ETI+T
Specifications of MAX1538ETI+T
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MAX1538ETI+T Summary of contents
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... QFN package with a maximum footprint of 5mm x 5mm. Notebook and Subnotebook Computers Internet Tablets Dual-Battery Portable Equipment Pin Configuration appears at end of data sheet. ________________________________________________________________ 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. Power-Source Selector for Dual-Battery Systems ...
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Power-Source Selector for Dual-Battery Systems ABSOLUTE MAXIMUM RATINGS EXTLD BATSUP ADPIN BATA BATB V to GND .................................................-0.3V to +30V CHGIN V to GND...................................-0. ADPPWR GND ...
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ELECTRICAL CHARACTERISTICS (continued 16.8V, C BATA BATB CHGIN VDD ADPPWR REVBLK ADPBLK DISBAT Typical values are +25°C.) A PARAMETER LINEAR REGULATOR V Output Voltage ...
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Power-Source Selector for Dual-Battery Systems ELECTRICAL CHARACTERISTICS (continued 16.8V, C BATA BATB CHGIN VDD ADPPWR REVBLK ADPBLK DISBAT Typical values are +25°C.) A PARAMETER ...
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ELECTRICAL CHARACTERISTICS ( 16.8V, C BATA BATB CHGIN VDD ADPPWR REVBLK ADPBLK DISBAT (Note 2) PARAMETER ADPIN, EXTLD Supply Voltage Range CHGIN, BATA, BATB, and BATSUP Supply Voltage ...
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Power-Source Selector for Dual-Battery Systems ELECTRICAL CHARACTERISTICS (continued 16.8V, C BATA BATB CHGIN VDD ADPPWR REVBLK ADPBLK DISBAT (Note 2) PARAMETER SYMBOL BAT_ Pack Removal Detection Threshold ...
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Figure +25°C, unless otherwise noted LOAD REGULATION DD 3.299 3.298 3.297 3.296 3.295 3.294 3.293 3.292 3.291 3.290 0 0.05 0.10 0.15 V LOAD CURRENT (mA BAT_ 4.0 BAT_ NOT HIGHEST ...
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Power-Source Selector for Dual-Battery Systems (Circuit of Figure +25°C, unless otherwise noted.) A BATTERY INSERTION A SYSTEM LOAD = 16.8V BATB 5.00ms/div A: CONTACT BOUNCE B: BATTERY INSERTION BLANKING TIME = 22ms BATTERY ...
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Figure +25°C, unless otherwise noted.) A BREAK-BEFORE-MAKE TIMING t TRANS MOSFET TURN-OFF TIME MOSFET TURN-ON TIME MOSFET FOR INITIAL DISCHARGE PATH MOSFET FOR FINAL DISCHARGE PATH 1.00µs/div PIN NAME Minimum Battery A Voltage Set Point. ...
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Power-Source Selector for Dual-Battery Systems PIN NAME Gate Drive for the Adapter-Blocking P-Channel MOSFET. Connect ADPBLK to the gate of P3 (Figure 1 ADPBLK enables and disables the battery discharge path. ADPBLK is driven relative to EXTLD. ADPBLK ...
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STEP-DOWN CHARGER SYSTEM LOAD CHARGER INPUT C SYS CHARGER OUTPUT C CHG Figure 1. Step-Down Typical Application Circuit ______________________________________________________________________________________ Power-Source Selector for Dual-Battery Systems ADAPTER FOR RELEARN P1 MODE ONLY P2 R SNS OUT ...
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Power-Source Selector for Dual-Battery Systems STEP-UP CHARGER CHARGER INPUT CHARGER OUTPUT C CHG SYSTEM LOAD C BATB Figure 2. Typical Application Circuit for Step-Up/Step-Down Charger 12 ______________________________________________________________________________________ ADAPTER AIRDET ADPIN FOR RELEARN P1 ADPPWR MODE ...
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BATB R MINVB 4R BATA R MINVA ACDET 2V AIRDET CHRG BATSEL RELRN BATSUP V DD REF GND Figure 3. Functional Diagram ______________________________________________________________________________________ Power-Source Selector for Dual-Battery Systems BATTERY B UNDERVOLTAGE 0.4V LATCH BATTERY A ...
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Power-Source Selector for Dual-Battery Systems Detailed Description The MAX1538 performs power path selection between an adapter input and two batteries, relieving the host system from the burden of real-time response to power- source changes. The integrated selector implements a fixed ...
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ADAPTER ADAPTER ADAPTER ADAPTER SWITCH SWITCH SYSTEM SYSTEM BATTERY BATTERY SWITCH SWITCH CHARGER CHARGER "A" "B" "A" "B" SWITCH SWITCH SWITCH SWITCH CHARGE DISCHARGE/ RELEARN Figure 4. MAX1538 Selection States Battery Presence and Undervoltage Detection The MAX1538 determines battery absence ...
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Power-Source Selector for Dual-Battery Systems Airline Mode and AC Adapter The MAX1538 provides compatibility with airline adapters. For airplane safety, the use of an airline adapter requires that the battery charger or charge path is disabled. The MAX1538 disables the ...
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Toggle CHG to enable the charge path to the battery. Charge control is overridden by RELRN (see the Battery Relearn Mode section) or airline mode (see the Airline Mode and AC Adapter section). When CHG is enabled, the MAX1538 connects ...
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Power-Source Selector for Dual-Battery Systems MOSFETs, they should be paired as shown in for optimal power dissipation. The MAX1538 provides asymmetric MOSFET gate drive, typically turning MOSFETs on faster than they are turned off. The t timer ensures that the ...
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V OR AC/AIR THRESHOLD MINV EXTLD MINV ADP t OFF ADPBLK/REVBLK t TRANS REVBLK/ADPBLK Figure 8. System Holdup Capacitor Timing crash, and C is the total system holdup capaci- SYS tance, which does not need ...
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Power-Source Selector for Dual-Battery Systems where V is the minimum battery voltage, BAT__MIN I is the maximum charge current, and L CHG_MAX the battery’s inductance. C values of 0.01µF are BAT_ adequate for typical applications. Adding capacitance at BAT_ pins ...
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Figure 10. MAX1538 Layout Example ______________________________________________________________________________________ Power-Source Selector for Dual-Battery Systems R10 ...
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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. 22 ____________________Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 © 2004 Maxim Integrated Products 0. ...