Texas Instruments recommends a compact layout with the BQ2204ASNTR placed close to the battery, and the input capacitors (CIN) placed as close as possible to the device. The output capacitor (COUT) should be placed near the load. A 4-layer PCB with a solid ground plane is recommended to minimize noise and EMI.
To minimize IQ, ensure that the EN pin is driven from a low-impedance source, and the input voltage (VIN) is as close to the output voltage (VOUT) as possible. Also, use a low-value resistor (RFB) in the feedback network, and consider using a low-IQ mode (e.g., pulse-frequency modulation) if the application allows it.
Although the datasheet specifies a maximum input voltage of 6.5V, the device can handle up to 7V for short durations (e.g., during power-up or voltage transients). However, sustained operation above 6.5V may reduce the device's reliability and lifespan.
To ensure stability, use a minimum output capacitance (COUT) of 10uF, and a maximum equivalent series resistance (ESR) of 1 ohm. Also, ensure that the input capacitance (CIN) is sufficient to filter out high-frequency noise. Additionally, consider adding a small ceramic capacitor (e.g., 100nF) in parallel with COUT to improve stability.
The BQ2204ASNTR is rated for operation up to 85°C (junction temperature). However, the device's performance and reliability may degrade at higher temperatures. If your application requires operation above 85°C, consider using a heat sink or a thermally enhanced package, and ensure that the device is properly derated.
BQ2204ASNTR datasheet
by Texas Instruments
