SGM8909.pdf
No.11229
? 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
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.
