DS2711E+ Maxim Integrated Products, DS2711E+ Datasheet
DS2711E+
Specifications of DS2711E+
Related parts for DS2711E+
DS2711E+ Summary of contents
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DESCRIPTION The DS2711 and DS2712 are ideal for in-system or stand-alone charging AAA NiMH “loose” cells. Temperature, voltage, and charge time are monitored to provide proper fast charging control algorithms for nickel metal ...
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... DS2712 DS2711Z+ DS2711 DS2711Z+T&R DS2711 DS2712Z+ DS2712 DS2712Z+T&R DS2712 DS2711E+ DS2711 DS2711E+T&R DS2711 DS2712E+ DS2712 DS2712E+T&R DS2712 + Denotes lead-free package. ABSOLUTE MAXIMUM RATINGS* Voltage on All Pins Relative to V Voltage on DMSEL Continuous Sink Current CC1, CC2, LED1, LED2 and CSOUT Operating Temperature Range ...
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PARAMETER SYMBOL Input Logic-High, DMSEL, LED2 Input Logic-Low, DMSEL, LED2 Input Leakage Current, DMSEL Threshold Voltage, Cell V Test Threshold Voltage, Cell V Voltage Low Threshold Voltage, Cell V BAT-MAX1 Voltage Max1 Threshold Voltage, Cell V BAT-MAX2 Voltage Max2 Threshold ...
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PARAMETER SYMBOL Duty Factor, Parallel Precharge/Top-Off Duty Factor, Maintenance Charge Cell Test Interval Precharge Time-Out Fast-Charge Termination Hold-Off Period Fast-Charge Flat Voltage Time-Out Charge Timer Period Charge Timer Accuracy Charge Timer Range t CTMR-RANGE Note 1: Voltages relative to V ...
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Figure 1. BLOCK DIAGRAM ...
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Figure 2. STATE DIAGRAM VDD < VPOR -VHYS (asynchronously from anywhere) POR Standby power CCx = Hi-Z LEDx = Hi-Z t < PCTimeout PreCHG OR CCx = Active 12.5% Par., 25% Ser. VBAT < 1V LEDx = Charging VBAT > ...
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DETAILED DESCRIPTION Charge Algorithm Overview A charge cycle begins in one of three ways: with the application of power to the DS2711 with cell(s) already inserted, with the detection of cell insertion after power-up, or when exiting suspend mode with ...
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Parallel Charge Configuration The parallel configuration supports two slot stand-alone chargers. Charge pulses are fed alternately to each cell under the control of the CC1 and CC2 pins so the charge regimes occur in parallel. The duty cycle on CC1 ...
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DS2712 Parallel Charge Configuration with Switch-Mode Charge Current Regulation The example in Figure 5 uses the DS2712 to regulate charge current as a switching (buck) regulator. ICHG is set to 2A using RSNS = 0.056Ω. The effective charge current for ...
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Undervoltage Lockout (UVLO) The UVLO circuit serves as a power-up and brownout detector by monitoring V rises above when V UVLO DD machine is forced to the RESET state, and all charge timers are reset. A 10μs ...
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Charge Timer The charge timer monitors the duration of charge in fast and top-off charge phases, and is reset at the beginning of each phase. The time-out period is set with an external resistor connected from the TMR pin to ...
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Cell Voltage Monitoring In the 2-cell series mode, the voltage difference between VP2 and VP1 is used to determine the Vcell2 voltage in the two-cell series stack. The voltage difference between VP1 and VN1 is used to determine the Vcell1 ...
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Table 3. CHARGE MODE SELECTION LED2 PIN STRAPPING Low Floating High CC1 and CC2 Outputs The CC1 and CC2 operate as open-drain outputs that drive active low to connect the charge source to the battery cell. During charge, the behavior ...
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Table 4. PARALLEL CONFIGURATION, EACH CELL MODE Cell Capacity 900mAH Fast C/3.72 Precharge/Top-Off C/14.4 Maintenance C/115 Series and Single Cell Charging Example: In the series and single-cell modes, the effective fast charge current is equal to 0.969 times the regulated ...
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REVISION HISTORY REVISION DATE Changed Figure 2 to include “T <0” condition to move from Pre-Charge to 120808 Fault state. DESCRIPTION PAGES CHANGED 6 ...