Audio Line Driver with Power On/Off Timing Control
SGM8909 SGM8909.pdf

No.11229

FEATURES

 Capless Structure to Eliminates Pop-Clicks and Output 

  DC-Blocking Capacitors

 2.8V to 5.5V Supply Voltage

 Low Noise, Low THD and Low Crosstalk:

 SNR = 107dB at Gain = -1, 600Ω Load for 5V VCC

 Typical VN = 8.7μVrms from 20Hz to 20kHz at Gain = -1

 THD+N = 0.007% for 600Ω Load and Gain = -1

 Crosstalk is -87dB at 1kHz

 3Vrms Output Voltage into 600Ω Load for 5V VCC

 2Vrms Output Voltage into 600Ω Load for 3.3V VCC

 Supports 32Ω Headset: 30mW at VCC = 3.3V

 Single-Ended Input and Output

 Programmable Gain by Single External Resistor

 Active Mute with More than -90dB Attenuation

 UVP Function to Eliminate Turn Off Click-Pop Noise

 Integrated Audio Filter

 Adjustable Power-On Blanking Time to Eliminate Turn on 

  Click-Pop Noise

 Short-Circuit and Thermal Protection

 -40℃ to +85℃ Operating Temperature Range

 Available in the Green TSSOP-14 Package

DESCRIPTION

The SGM8909 is a single-ended, 3Vrms stereo audio line driver with integrated audio filter. It can reduce external component count, board space and cost. It is ideal for audio applications where single power supply, size and cost are critical design parameters.

The SGM8909 integrates a charge pump to generate a negative supply rail that provides a clean, pop-free ground-biased output. The SGM8909 is capable of driving 3Vrms into a 600Ω load when VCC is 5V or 30mW into 32Ω headset when VCC is 3.3V. Capless output structure allows the removal of the costly output DC-blocking capacitors.

The device has a gain programming pin. With a single resistor from this pin to ground, device gain can be changed to match the line driver with the codec output level. It also reduces the component count and board space.

The SGM8909 will be in mute status during power-on blanking time. External mute control can take over the mute status before power-on blanking time is over, and the SGM8909 can eliminate power up Click-Pop noise perfectly. With the under-voltage protection (UVP) function, SGM8909 will minimize the turn off Click-Pop noise perfectly.

APPLICATION CIRCUIT
PIN CONFIGUTION
Site Map