19-5826; Rev 4/11
GENERAL DESCRIPTION
The DS2711 and DS2712 are ideal for in-system or
stand-alone charging of 1 or 2 AA or AAA NiMH
“loose” cells. Temperature, voltage, and charge time
are monitored to provide proper fast-charging control
algorithms for nickel metal hydride (NiMH) batteries.
Battery tests are included to detect defective or
inappropriate cells such as alkaline primary batteries.
The DS2711/DS2712 support series and parallel
topologies, with independent monitoring and control of
each cell. Charging of NiCd chemistry cells is also
supported.
APPLICATIONS
Desktop/Stand-Alone Chargers (AAA/AA)
Digital Still Cameras
Music Players
Games
Toys
FEATURES
Charge 1 or 2 NiMH Cells
Detect and Avoid Charging Alkaline Cells
Precharge Deeply Depleted Cells
Fast Charge NiMH with -∆V Termination
Sensitivity of 2mV (typ)
Monitor Voltage, Temperature, and Time for
Safety and Secondary Termination
Regulate Charge Current:
Linear Control (DS2711)
Switch-Mode Control (DS2712)
Drive pMOS or pnp-Type Pass Element or
Switch, or an Optocoupler
Compatible with Popular Optocouplers and
Integrated Primary-Side PWM Controllers
Small 16-Pin SO or TSSOP Packages
DS2711/DS2712
Loose-Cell NiMH Chargers
PIN CONFIGURATION
CC1
CC2
LED1
VSS
LED2
CSOUT
VN1
VN0
1
2
3
4
5
6
7
8
16 VP2
15 VP1
14 THM2
13 THM1
12 VDD
11 TMR
10 CTST
9 DMSEL
SO (150 mils)
TSSOP (4.4mm)
PIN DESCRIPTION
PIN NAME
FUNCTION
1 CC1 Cell 1 Charge-Control Output
2 CC2 Cell 2 Charge-Control Output
3 LED1 Cell 1 Status
4
VSS
Ground Reference and Chip-
Supply Return
5 LED2 Cell 2 Status, Mode-Select Input
6 CSOUT Current-Sense Output
7 VN1 Current-Sense + Input
8 VN0 Current-Sense - Input
9 DMSEL Display-Mode Select
10 CTST Cell Test Threshold Set
11 TMR Charge Timer Set
12 VDD Chip-Supply Input (4.0V to 5.5V)
13 THM1 Cell 1 Thermistor Input
14 THM2 Cell 2 Thermistor Input
15
VP1
Cell 1 Positive-Terminal Sense
Input
16
VP2
Cell 2 Positive-Terminal Sense
Input
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