The SGM4917 stereo headphone amplifier is designed for portable equipment where board space is at a premium. The SGM4917 uses capless architecture to produce a ground-referenced output from a single power supply, eliminating the need for large DC-blocking capacitors for output, saving cost, board space, and component height. Additionally, for SGM4917B, the gain is set internally (-2V/V), further reducing component count. For SGM4917A, the gain can be adjusted by external feedback resistors.
The SGM4917 delivers up to 80mW per channel into a 32Ω load and has low 0.02% THD+N. A -78dB power supply rejection ratio (PSRR) at 217Hz 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.
The SGM4917 operates from a single 2.7V to 5.5V supply, consumes only 2.7mA supply current, and is specified over the extended -40℃ to +85℃ temperature range. The SGM4917 is available in a Green TQFN-3×3-16L package.
SGM4917A: External Feedback Gain Network
SGM4917B: Fixed -2V/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
80mW into 32Ω Load from 5V Power Supply at THD+N = 0.1% (TYP, per Channel)
Low 0.02% THD+N
High PSRR (-78dB at 217Hz)
Integrated Click-and-Pop Suppression
2.7V to 5.5V Single Supply Operation
Low Quiescent Current (2.7mA at VDD = 5V)
Shutdown Control
Under-Voltage Lockout Function
-40℃ to +85℃ Operating Temperature Range
Available in Green TQFN-3×3-16L Package
Notebook PCs
Cellular Phones
PDAs
MP3 Players
Smart Phones
Portable Audio Equipment
| Part Number | Status | Package | Pins | Pb-Free | Temp Range |
| SGM4917AYTQ16G/TR | Production | TQFN-3×3-16L | 16 | Y | -40℃ to +85℃ |
| SGM4917BYTQ16G/TR | Production | TQFN-3×3-16L | 16 | Y | -40℃ to +85℃ |
