The SSM2306 is a fully integrated, high efficiency, Class-D stereo
audio amplifier designed to maximize performance for portable
applications. The application circuit requires minimum external
components and operates from a single 2.5 V to 5.0 V supply. It
is capable of delivering 2 W of continuous output power with less
than 10% total harmonic distortion plus noise (THD + N)
driving a 4 Ω load from a 5.0 V supply.
The SSM2306 features an ultralow idle current, high efficiency,
and a low noise modulation scheme. It operates with >87%
efficiency at 1.4 W into 8 Ω from a 5.0 V supply and has a
signal-to-noise ratio (SNR) that is better than 96 dB. Pulse-density
modulation (PDM) offers lower electromagnetic
interference (EMI) radiated emissions compared to other
Class-D architectures.
The SSM2306 has a micropower shutdown mode with a typical
shutdown current of 20 nA. Shutdown is enabled by applying a
logic low to the SD pin.
The architecture of the device allows it to achieve a very low level
of pop and click to minimize voltage glitches at the output during
turn-on and turn-off, thereby reducing audible noise on activation
and deactivation. The fully differential input of the SSM2306
provides excellent rejection of common-mode noise on the input.
Input coupling capacitors can be omitted if the dc input
common-mode voltage is approximately VDD/2.
The SSM2306 also has excellent rejection of power supply noise,
including noise caused by GSM transmission bursts and RF
rectification.
The SSM2306 has a preset gain of 18 dB that can be reduced by
using external resistors.
The SSM2306 is specified over the commercial temperature range
(−40°C to +85°C). It has built-in thermal shutdown and output
short-circuit protection. It is available in a 16-lead, 3 mm × 3 mm
lead frame chip scale package (LFCSP).
APPLICATIONS
- Mobile phones
- MP3 players
- Portable gaming
- Portable electronics
- Educational toys
- Notebook computers
