The recommended power-on sequence is to apply the power supply voltage (VCC) before applying the audio signal. This ensures that the internal biasing and voltage regulators are stable before the audio signal is applied.
The gain of the LM4550 can be optimized by adjusting the values of the external resistors (R1 and R2) and capacitors (C1 and C2) in the feedback network. The gain can be calculated using the formula: Gain = (R2/R1) * (C2/C1).
The maximum power dissipation of the LM4550 is 1.4W. This is calculated based on the maximum junction temperature (TJ) of 150°C and the thermal resistance (RθJA) of 125°C/W.
Yes, the LM4550 can be used as a headphone amplifier. However, it's essential to ensure that the output power is limited to avoid damaging the headphones or the amplifier. A maximum output power of 100mW per channel is recommended.
To reduce noise and hum, ensure that the power supply is well-regulated and decoupled, use a low-noise voltage regulator, and add bypass capacitors to the power supply lines. Additionally, use shielded cables and keep the audio signal lines away from the power supply lines.
LM4550BVH/NOPB datasheet
by Texas Instruments
