Things to Consider When using BQ24074 Charger IC on Your PCB

➡️️ The BQ24074 is a compact Li-Ion/Li-Poly linear charger IC with power path management, ideal for safe battery charging in portable electronics. 

Essential Design Tips:

Does the IC have reverse voltage protection?

The BQ24074 does not have reverse-voltage protection on its input.  Applying a reverse voltage to the input of the BQ24074 can damage the IC.

 Is it possible to charge more than one battery with BQ24074?

No, the BQ24074 is designed to charge single-cell lithium-ion/polymer batteries.

What is the maximum input voltage BQ24074 can handle?

The absolute maximum voltage BQ24074 can handle is 28V. The recommended maximum input voltage is 10.2V and the over-voltage protection will be triggered at 10.5V.

Are there any ready-made modules available for BQ24074?

You can find various BQ24074 solar chargers and battery charging modules for single-cell batteries. The ability to handle higher absolute maximum voltage makes the BQ24074 a perfect choice for such small solar applications.

What are the design considerations when designing a PCB using BQ24074?

The BQ24074 is packaged in a thermally enhanced MLP package. The package includes a thermal pad to provide effective thermal contact between the IC and the printed circuit board (PCB). The power pad should be directly connected to the VSS pin.

• To obtain optimal performance, the decoupling capacitor from IN to GND (thermal pad) and the output filter capacitors from OUT to GND (thermal pad) should be placed as close as possible to the BQ24074, with short trace runs to both IN, OUT and GND (thermal pad).

•  All low-current GND connections should be kept separate from the high-current charge or discharge paths from the battery. Use a single-point ground technique incorporating both the small signal ground path and the power ground path. 

• The high current charge paths into the IN pin and from the OUT pin must be sized appropriately for the maximum charge current in order to avoid voltage drops in these traces. 

• The BQ24074 family is packaged in a thermally enhanced MLP package. The package includes a thermal pad to provide effective thermal contact between the IC and the printed circuit board (PCB); this thermal pad is also the main ground connection for the device. Connect the thermal pad to the PCB ground connection. Full PCB design guidelines for this package are provided in the QFN/SON PCB Attachment Application Note. 

➡️Applications: TWS Charging Case

➡️Alternatives: LTC4054, MAX1555

➡️Datasheet: BQ24074 Datasheet

➡️Manufacturer: Texas Instruments