GENERAL DEscriptION
The SGM4917 is stereo headphone amplifier which is designed for portable applications and can operate from a 2.7V to 5.5V single supply. Capless design can produce a ground-referenced output from a single power supply, and can eliminate output DC-blocking capacitors for less-component height and low-cost. For SGM4917B, the internal gain setting (-2V/V) is to further reduce component count. For SGM4917A, the gain can be adjusted by external feedback resistors.
The SGM4917 has low quiescent current 2.7mA at 5V supply, low 0.02% THD+N, 80mW per channel into 32Ω load from 5V power supply at THD+N = 0.1%. The high supply rejection ratio (PSRR) of -78dB at 217Hz allows the device to operate from noisy digital supplies without an additional linear regulator. The device provides short-circuit and thermal-overload protections. Build-in shutdown control also helps for pop/click-free on/off control.
The SGM4917 is available in a Green TQFN-3×3-16L package. It operates over an ambient temperature range of -40℃ to +85℃
FEATURES
Supply Voltage Range: 2.7V to 5.5V
SGM4917A: External Feedback Gain Network
SGM4917B: Fixed -2V/V Gain
Capless Structure
Eliminates Ground-Referenced Outputs
Eliminates Output DC-Blocking Capacitors
Provides Flat Frequency Response
80mW into 32Ω Load from 5V Power Supply at THD+N = 0.1% (Typical, per Channel)
THD+N = 0.02% (f = 1kHz)
High PSRR: -78dB (at 217Hz)
Quiescent Current: 2.7mA (TYP)
Shutdown Control
Short-Circuit and Thermal-Overload Protections
Under-Voltage Lockout Function
Enhanced Noise Cancellation by Differential Inputs
-40℃ to +85℃ Operating Temperature Range
Available in a Green TQFN-3×3-16L Package
APPLICATIONS
Smart Phones
Portable Audio Equipment
Notebook PCs
PDAs