Document
Rev 0; 4/08
Single-Cell NiMH Charger
General Description
The DS2710 is ideal for in-system charging of single-cell nickel metal hydride (NiMH) cells for low-current portable applications. Inputs to the DS2710 include USB voltage sources and 5V regulated adapters. Temperature, voltage, and charge time are monitored to provide proper fast-charging control algorithms for single-cell NiMH or nickel cadmium (NiCd) batteries. The DS2710 includes battery tests to detect defective or inappropriate cells such as alkaline primary batteries. ♦ Charges Single-Cell NiMH Cells ♦ Switch-Mode Topologies Supported by Hysteretic Control Technique ♦ Precharges Deeply Depleted Cells ♦ Fast-Charges NiMH with -ΔV Termination Sensitivity of 2mV (typ) ♦ Monitors Voltage, Temperature, and Time for Safety and Secondary Termination ♦ Regulates Charge Current ♦ Designed for External pMOS ♦ Rail-to-Rail MOSFET Driver ♦ Tiny 10-Pin TDFN Package (3mm x 4mm)
Features
DS2710
Applications
Small Rechargeable Devices Voice Recorders Cordless Mouse Battery-Powered Toys
Ordering Information
PART DS2710G+ DS2710G+T&R PIN-PACKAGE 10 TDFN-EP* 10 TDFN-EP*
+Denotes a lead(Pb)-free/RoHS-compliant package. T&R = Tape and reel. *EP = Exposed pad.
Typical Operating Circuit
TOP VIEW
CHARGE SOURCE VSS CS VDD VP1 CS VDD THM THM VN0 SENSE GROUND *EXPOSED PAD. VN1 NiMH CELL STATUS 1 2 3 4 5 *EP
Pin Configuration
+
10 9
VP1 VN1 VN0 TMR CTEST
DS2710
8 7 6
DS2710
TDFN (3mm × 4mm)
________________________________________________________________ Maxim Integrated Products
1
For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
Free Datasheet
http://www.datasheet4u.com/
Single-Cell NiMH Charger DS2710
ABSOLUTE MAXIMUM RATINGS
Voltage Range on All Pins Relative to VSS ............-0.3V to +6.0V Continuous Source/Sink Current CS ...................................20mA Continuous Source Current STATUS ..................................10mA Operating Temperature Range ...........................-40°C to +85°C Storage Temperature Range .............................-55°C to +125°C Soldering Temperature...........................Refer to the IPC/JEDEC J-STD-020 Specification.
Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
RECOMMENDED DC OPERATING CONDITIONS
(4.0V ≤ VDD ≤ 5.5V, TA = -20°C to +70°C.)
PARAMETER Supply Voltage Input Voltage Range SYMBOL VDD (Note 1) CTEST, TMR, THM, VP1, VN1 CONDITIONS MIN 4.0 -0.3 TYP MAX 5.5 VDD UNITS V V
DC ELECTRICAL CHARACTERISTICS
(4.0V ≤ VDD ≤ 5.5V, TA = -20°C to +70°C, unless otherwise noted.)
PARAMETER Supply Current, VDD UVLO Threshold UVLO Hysteresis Output-Voltage Low, CS Output-Voltage High, CS Output-Voltage Low, STATUS Output-Voltage High, STATUS Threshold Voltage, -V Termination Current-Sense Reference Voltage Hysteresis, Current-Sense Comparator Propagation Time, Current-Sense Comparator to Driver Output CS Pin Pullup Current STATUS Pin Pulldown Current Depleted Cell Voltage Threshold Overcharge Voltage Threshold Open Socket Voltage Threshold Offset, VMAX-OPEN - VMAX-CHARGE SYMBOL IDD VUVLO VUHYS VOL1 VOH1 VOL2 VOH2 V-V VIREF VHYSCOMP t PDLY ICS I STAT VLOW VMAXOPEN
CONDITIONS Operating mode (Note 2) VDD rising (Note 1) VDD falling from above VUVLO VDD = 5.0V, I OL = +20mA (Note 1) VDD = 5.0V, I OL = -20mA (Note 1) VDD = 5.0V, I OL = +2mA (Notes 1, 3) VDD = 5.0V, I OH = -2mA (Notes 1, 3) After tTHO (Note 4) (Notes 1, 5) Centered ~ 0.113V 2mV overdrive/underdrive at trip threshold (Notes 4, 6) VDD < VUVLO (Note 4) VDD < VUVLO (Note 4) VP1 - VN1 VP1 - VN1, CS = high (Note 7) VP1 - VN1, CS = low (Note 7) (Note 7)
MIN
TYP 250 3.5
MAX 1000 3.9 1.0
UNITS μA V mV V V V V
30 4.0 0.50 4.0 1.0 2.0 125 -6 18 23 +6 27 0.1 2 2 0.9 1.55 1.64 98 1.0 1.65 1.75 100 10 10 1.1 1.75 1.86 102 3.0
mV mV % mV μs μA μA V V V mV
VMAXCHARGE
VOS
2
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Single-Cell NiMH Charger
DC ELECTRICAL CHARACTERISTICS (continued)
(4.0V ≤ VDD ≤ 5.5V, TA = -20°C to +70°C, unless otherwise noted.)
PARAMETER Cold Temperature Detect Threshold Hot Temperature No-Start Threshold Hot Temperature Safety Shutdown Threshold SUSPEND Current Threshold Presence-Test Current, VP1 Reverse-Leakage Current, VP1 Impedance-Voltage Test Range VCTEST SYMBOL VTHM-MIN VTHM-MAX (Notes 1, 5, 8) (Notes 1, 5, 8) 0.30 CONDITIONS MIN TYP 0.73 0.33 0.29 0.1 1.0 32 10 0.5 15 2 400 0.36 MAX UNITS VDD VDD VDD μA μA μA mV
DS2710
VTHM-STOP (Notes 1, 5, 8) I SUSPEND (Note 9) VDD 4.0V VDD = 0V, VP1 = 1.5V
ELECTRICAL CHARACTERISTICS: TIMING
(4.0V ≤ VDD.