SSM2356CBZ-RL Datasheet, PDF (1/16 Pages) Analog Devices – 2 x 2W Filterless Class-D Stereo Audio Amplifier

Data Sheet
2 × 2W Filterless Class-D
Stereo Audio Amplifier
SSM2356
FEATURES
Filterless stereo Class-D amplifier with Σ-Δ modulation
No sync necessary when using multiple Class-D amplifiers
from Analog Devices, Inc.
2 × 2W into 4 Ω load and 2x1.4 W into 8 Ω load at 5.0 V
supply with <1% total harmonic distortion (THD + N)
92% efficiency at 5.0 V, 1.4 W into 8 Ω speaker
>103 dB signal-to-noise ratio (SNR)
Single-supply operation from 2.5 V to 5.5 V
20 nA shutdown current; left/right channel control
Short-circuit and thermal protection
Available in a 16-ball, 1.66 mm × 1.66 mm WLCSP
Pop-and-click suppression
Built-in resistors that reduce board component count
User-selectable 6 dB or 18 dB gain setting
User-selectable ultralow EMI emission mode
APPLICATIONS
Mobile phones
MP3 players
Portable gaming
Portable electronics
GENERAL DESCRIPTION
The SSM2356 is a fully integrated, high efficiency, stereo Class-D
audio amplifier. It is designed to maximize performance for
mobile phone applications. The application circuit requires
a minimum of external components and operates from a single
2.5 V to 5.5 V supply. It is capable of delivering 2 × 2W of contin-
uous output power with <1% THD + N driving a 4 Ω load from a
5.0 V supply.
The SSM2356 features a high efficiency, low noise modulation
scheme that requires no external LC output filters. The modulation
continues to provide high efficiency even at low output power.
It operates with 92% efficiency at 1.4 W into 8 Ω or 85% efficiency
at 2.0 W into 4 Ω from a 5.0 V supply and has an SNR of >103 dB.
Spread-spectrum pulse density modulation is used to provide
lower EMI-radiated emissions compared with other Class-D
architectures. The SSM2356 includes an optional modulation
select pin (ultralow EMI emission mode) that significantly
reduces the radiated emissions at the Class-D outputs, particularly
above 100 MHz.
The SSM2356 has a micropower shutdown mode with a typical
shutdown current of 20 nA. Shutdown is enabled by applying
a logic low to the SDNR and SDNL pins. The device also
includes pop-and-click suppression circuitry that minimizes
voltage glitches at the output during turn-on and turn-off,
reducing audible noise on activation and deactivation.
The fully differential input of the SSM2356 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 preset gain of SSM2356 can be
selected between 6 dB and 18 dB with no external components
and no change to the input impedance. Gain can be further
reduced to a user-defined setting by inserting series external
resistors at the inputs.
The SSM2356 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-ball, 1.66 mm ×
1.66 mm wafer level chip scale package (WLCSP).
FUNCTIONAL BLOCK DIAGRAM
22nF¹
RIGHT IN+
RIGHT IN–
22nF¹
SHUTDOWN–R
SHUTDOWN–L
LEFT IN+
22nF¹
LEFT IN–
22nF¹
10µF
0.1µF
VBATT
2.5V TO 5.5V
SSM2356
80kΩ
INR+
INR– _80kΩ
GAIN
CONTROL
VDD
VDD
MODULATOR
(Σ-Δ)
FET
DRIVER
OUTR+
OUTR–
SDNR
SDNL
80kΩ
INL+
INL– _80kΩ
GAIN
CONTROL
GAIN
BIAS
BIAS
INTERNAL
OSCILLATOR
MODULATOR
(Σ-Δ)
GND
EDGE
CONTROL
FET
DRIVER
GND
EDGE
OUTL+
OUTL–
EMISSION
CTRL
GAIN
GAIN = 6dB OR 18dB
1 _{INPUT CAPS ARE OPTIONAL IF INPUT DC COMMON-MODE}
VOLTAGE IS APPROXIMATELY V_DD/2.
Figure 1.
Rev. A
Document Feedback
Information furnished by Analog Devices is believed to be accurate and reliable. However, no
responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other
rights of third parties that may result from its use. Specifications subject to change without notice. No
license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
Trademarks and registered trademarks are the property of their respective owners.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: [phone] ©2009–2013 Analog Devices, Inc. All rights reserved.
Technical Support
www.analog.com