SGM4917

Preliminary Datasheet SGM4917 125mW, Capless, Stereo Headphone Amplifier with Shutdown GENERAL DESCRIPTION The SGM4917 stereo headphone amplifier is designed for portable equipment where board space is at a premium. The SGM4917 uses capless Direct-drive architecture to produce a ground-referenced output from a single power supply, eliminating the need for large DC-blocking capacitors for output, and saving cost, board space, and component height. Additionally, for SGM4917B and SGM4917C, the gain is set internally (-2V/V or -1.5V/V), further reducing component count. For SGM4917A, the Gain can be adjusted by external feedback resistors. The SGM4917 delivers up to 125mW per channel into a 32Ω load and has low 0.02% THD+N. A 78dB at 217Hz power-supply rejection ratio (PSRR) allows this device to operate from noisy digital supplies without an additional linear regulator. Comprehensive click-and-pop circuitry suppresses audible clicks and pops on startup and shutdown. FEATURES SGM4917A: External Feedback Gain Network SGM4917B: Fixed -2V/V Gain SGM4917C: Fixed -1.5V/V Gain No Bulky DC-Blocking Capacitors Required Ground-Referenced Outputs Eliminate DC-Bias Voltage on Headphone Ground Pin No Degradation of Low-Frequency Response Due to Output Capacitors Differential Inputs for Enhanced Noise Cancellation 125mW per Channel into 32Ω Headset Low 0.02% THD+N High PSRR (78dB at 217Hz) Integrated Click-and-Pop Suppression 2.7V to 5.5V Single Supply Operation Low Q...