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MAX1645A
Advanced-Chemistry-Independent, Level-2 Battery Chargers with Input Current Limiting
SMBus™ Controlled, Chemistry Independent Smart Battery Charger with Input Current Limiting and Safety Timer
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Key Features
Applications/Uses
Parametric specs for Battery Chargers
| Charging VIN (V) (max) | 28 |
| Max. ICHG (A) | 3 |
| Lithium Ion Cells | 2 3 4 |
| Protected VIN (V) (max) | 28 |
| Charge Rate Set by | I2C/SMBus Resistor |
| Charge Termination | Smart Battery Control |
| Charge Regulation | Switchmode |
| Oper. Temp. (°C) | -40 to +85 |
| Package/Pins | See Data Sheet |
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Parameters
Parametric specs for Battery Chargers
| Charging VIN (V) (max) | 28 |
| Max. ICHG (A) | 3 |
| Lithium Ion Cells | 2 3 4 |
| Protected VIN (V) (max) | 28 |
| Charge Rate Set by | I2C/SMBus Resistor |
| Charge Termination | Smart Battery Control |
| Charge Regulation | Switchmode |
| Oper. Temp. (°C) | -40 to +85 |
| Package/Pins | See Data Sheet |
Key Features
- Input Current Limiting
- 175sec Charge Safety Timeout
- 128mA Wake-Up Charge
- Charges Any Chemistry Battery: Li+, NiCd, NiMH, Lead Acid, etc.
- Intel SMBus 2-Wire Serial Interface
- Compliant with Level 2 Smart Battery Charger Spec. Rev. 1.0
- +8V to +28V Input Voltage Range
- Up to 18.4V Battery Voltage
- 11-Bit Battery Voltage Setting
- ±0.8% Output Voltage Accuracy with Internal Reference
- 3A max Battery Charge Current
- 6-Bit Charge Current Setting
- 99.99% max Duty Cycle for Low-Dropout Operation
- Load/Source Switchover Drivers
- >97% Efficiency
Applications/Uses
- Notebook Computers
- PDAs and Other Handheld Devices
- Point-of-Sale Terminals
Description
The MAX1645 is a high-efficiency battery charger capable of charging batteries of any chemistry type. It uses the Intel® System Management Bus (SMBus) to control voltage and current charge outputs.
When charging lithium-ion (Li+) batteries, the MAX1645 automatically transitions from regulating current to regulating voltage. The MAX1645 can also limit line input current so as not to exceed a predetermined current drawn from the DC source. A 175sec charge safety timer prevents "runaway charging" should the MAX1645 stop receiving charging voltage/current commands.
The MAX1645 employs a next-generation synchronous buck control circuitry that lowers the minimum input-to-output voltage drop by allowing the duty cycle to exceed 99%. The MAX1645 can easily charge one to four series Li+ cells.
When charging lithium-ion (Li+) batteries, the MAX1645 automatically transitions from regulating current to regulating voltage. The MAX1645 can also limit line input current so as not to exceed a predetermined current drawn from the DC source. A 175sec charge safety timer prevents "runaway charging" should the MAX1645 stop receiving charging voltage/current commands.
The MAX1645 employs a next-generation synchronous buck control circuitry that lowers the minimum input-to-output voltage drop by allowing the duty cycle to exceed 99%. The MAX1645 can easily charge one to four series Li+ cells.
Technical Docs
Support & Training
Search our knowledge base for answers to your technical questions.
Filtered SearchOur dedicated team of Applications Engineers are also available to answer your technical questions. Visit our support portal .
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