Features: ` Protects Against Overvoltage
` ±1% Accurate Protection Thresholds
` Integrated 2.1s Fault-Delay Timer
` Built-in 1.5A SCR Fuse Driver
` Test Mode for Functional Verification in Assembled Pack
` 8A (max) Supply Current
` 1A (max) Standby Current
` Protects Against Disconnected B1PB4P Pins
` Protects 2-, 3-, or 4-Series Li+ Battery Packs
` Available in Small 16-Pin QFN Package (5mm x 5mm)Application2-, 3-, or 4-Series Li+ Battery Packs for Portable ProductsPinout
SpecificationsB4P to BN ...............................................................-0.3V to +24V
B3P to BN ...............................................................-0.3V to +18V
B2P to BN ...............................................................-0.3V to +12V
B4P to B3P, B3P to B2P, B2P to B1P, B1P to BN .......-0.3V to +6V
TEST, DRV, DISCON to PKN.......................................-0.3V to +6V
OUT to BN ..............................................................-0.3V to +24V
BN to PKN ...................................................................-2V to +2V
OUT Maximum Current .........................................................2.5A
Continuous Power Dissipation (TA = +70°C, per JEDEC JESD51-7)
16-Pin QFN (derate 19mW/°C above +70°C ambient) ....1.5W
Operating Temperature Ranges..........................-40°C to +85°C
Storage Temperature........................................-65°C to +150°C
Junction Temperature.......................................................+150°C
Lead Temperature (soldering, 10s) .................................+300°C
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.
DescriptionThe MAX1906 protects against overvoltage conditions in lithium-ion/lithium polymer (Li+) battery packs by blowing a three-terminal protection fuse. The IC should be used in conjunction with resettable protection circuits to provide a high level of safety against overcharging Li+ batteries. It can be used with 2-, 3-, or 4-series cell battery packs.
The monitors individual cell voltages. If any cell voltage exceeds the overvoltage threshold for greater than 2.1s, the MAX1906 activates an internal SCR. The SCR sinks sufficient current to blow an external protection fuse, permanently disabling the battery pack. Alternatively, the IC can drive the gate of an external MOSFET to blow the fuse.
The MAX1906 also offers protection against disconnected voltage sense pins. If a disconnected pin is detected,the DISCON output is forced low. It includes a test mode, which determines if the circuit is operating correctly while in an assembled battery pack.
The low-cost MAX1906 is available in a thermally enhanced 16-pin QFN package.
MAX1906 Data Sheet
