Stereo 2-Vrms Line Driver and Headphone Amplifier

This is a 2V_rms Pop-Free stereo line driver with a stereo headphone driver designed to allow the removal of the output DC-blocking capacitors for reduced component count and cost. The project is based on the DRV604 chip which is ideal for single supply electronics where size and cost are critical design parameters. The project is capable of driving 2V_rms into a 5kΩ load and a clean 40mW into a 32Ω headphone with a single 3.3V supply voltage. Line and headphone outputs have ±8kV IEC ESD protection. The device has built-in shutdown control for pop-free on/off control. The DRV604 does not require a power supply greater than 3.3V to generate its 5.6V_pp output, nor does it require a split rail power supply. The DRV604 integrates its charge pump to generate a negative supply rail that provides a clean, pop-free ground biased 2V_rms output. This project is configured with single-ended header input connectors for analog input, headphones, and line output. The power supply is connected via a four-pin 2.54mm pin header.