MAX745
PRODUCTIONSwitch-Mode Lithium-Ion Battery-Charger
±0.75% Precision Li+ Charger Delivers 4A Without Heating
- Part Models
- 2
- 1ku List Price
- Starting From $8.76
Overview
- Charges 1 to 4 Li+ Battery Cells
- ±0.75% Voltage-Regulation Accuracy Using 1% Resistors
- Provides up to 4A without Excessive Heating
- 90% Efficient
- Uses Low-Cost Set Resistors and N-Channel Switch
- Up to 24V Input
- Up to 18V Maximum Battery Voltage
- 300kHz Pulse-Width Modulated (PWM) Operation
- Low-Noise, Small Components
- Stand-Alone Operation—No Microcontroller Needed
The MAX745 provides all functions necessary for charging lithium-ion (Li+) battery packs. It provides a regulated charging current of up to 4A without getting hot, and a regulated voltage with only ±0.75% total error at the battery terminals. It uses low-cost, 1% resistors to set the output voltage, and a low-cost N-channel MOSFET as the power switch.
The MAX745 regulates the voltage set point and charging current using two loops that work together to transition smoothly between voltage and current regulation. The per-cell battery voltage regulation limit is set between 4V and 4.4V using standard 1% resistors, and then the number of cells is set from 1 to 4 by pin-strapping. Total output voltage error is less than ±0.75%.
For a similar device with an SMBus™ microcontroller interface and the ability to charge NiCd and NiMH cells, refer to the MAX1647 and MAX1648. For a low-cost Li+ charger using a linear-regulator control scheme, refer to the MAX846A.
Applications
- Cell Phones
- Desktop Cradle Chargers
- Handheld Instruments (PDAs, Palmtops)
- Li+ Battery Packs
- Notebook Computers
Documentation
Data Sheet 1
Design Note 1
Technical Articles 2
Video 1
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal. View our quality and reliability program and certifications for more information.
| Part Model | Pin/Package Drawing | Documentation | CAD Symbols, Footprints, and 3D Models |
|---|---|---|---|
| MAX745EAP+ | 20-Lead SSOP (7.33mm x 5.38mm x 1.99mm) | ||
| MAX745EAP+T | 20-Lead SSOP (7.33mm x 5.38mm x 1.99mm) |
| Part Models | Product Lifecycle | PCN |
|---|---|---|
|
Jul 3, 2023 - 2361NA WAFER FAB |
||
| MAX745EAP+ | PRODUCTION | |
| MAX745EAP+T | PRODUCTION | |
|
Apr 20, 2026 - 2571B PIN/ERRATA |
||
| MAX745EAP+T | PRODUCTION | |
This is the most up-to-date revision of the Data Sheet.
Software Resources
Can't find the software or driver you need?
Request a Driver/SoftwareHardware Ecosystem
| Parts | Product Life Cycle | Description |
|---|---|---|
| Battery Charger ICs 3 | ||
| MAX846A | PRODUCTION | Cost-Saving, Multichemistry, Battery Charger System |
| MAX1640 | PRODUCTION | Adjustable-Output, Switch-Mode Current Sources with Synchronous Rectifier |
| MAX1647 | PRODUCTION | Chemistry-Independent Battery Chargers |
| Microcontrollers 1 | ||
| MAX1782 | Obsolete | Advanced Smart Battery-Pack Controller |
Evaluation Kits
Evaluation Kit for the MAX745