Advanced Li+ Battery-Pack Protectors
Smallest Li+ Protection Solution Also Offers the Most Complete Set of Features
DescriptionThe MAX1894/MAX1924 are lithium-ion/lithium-polymer (Li+) battery-pack protector ICs for 3- or 4-series Li+ battery packs. The MAX1894/MAX1924 enhance the useful operating life of Li+ batteries by monitoring individual cell voltages and preventing over/undervoltage conditions. The MAX1894/MAX1924 also protect the battery pack against charge current, discharge current, and pack-short fault conditions.
In case of a fault condition, on-board drivers control external P-channel MOSFETs, which disconnect the cells from the pack external terminals. The external protection MOSFETs are connected in a common-source configuration that does not require external pullup resistors. The MAX1894/MAX1924 use only one current-sense resistor to achieve the protection features. All protection thresholds and delays do not require any external components and are trimmed at the factory.
If any cell voltage drops below the undervoltage threshold, the MAX1894/MAX1924 disconnect the pack from the load and power down to prevent deep discharge of the pack. The MAX1894/MAX1924 offer a trickle-charge feature, which provides a low-current path to safely charge a deeply discharged pack. The MAX1894/ MAX1924 also have two logic-level inputs, which can be used by a microcontroller to disable the protection MOSFETs and to put the device in shutdown. The MAX1894/MAX1924 have low quiescent current (30µA typ) and ultra-low shutdown current (0.8µA typ) to prevent deep-cell discharge.
The MAX1894X is designed for 4-series battery packs, without hysteresis on the protection thresholds. The MAX1924V and MAX1924X include hysteresis for the 3- and 4-series packs, respectively.
- 3- or 4-Series Li+ Battery Packs
|Part Number||Functions||Battery Type||Parameters Measured||Applications||Battery Protection||VSUPPLY|
|MAX1924||Protector||3-4 Cell Li-Ion|
|-40 to +85|
|Device||Fab Process||Technology||Sample size||Rejects||FIT at 25°C||FIT at 55°C||Material Composition|
- 3.5V to 23V Input Operating Range, 30VDC Withstand Voltage
- Reverse Leakage Protection
- 50mA to 3.15A Programmable Input Current Limit
- Battery Health + Programmable Safety/Protection
- ModelGauge m5 EZ Algorithm
- Precision Measurement Without Calibration
- AEC-Q100 Grade 2 Temperature Range
- Operating Voltage from 9V to 65V
- Ultra-Low-Power Operation