SSM2302CPZ-REEL Analog Devices Inc, SSM2302CPZ-REEL Datasheet - Page 13

• Manufacturer Part Number: SSM2302CPZ-REEL
• Description: IC,Audio Amplifier,DUAL,LLCC,16PIN,PLASTIC
• Manufacturer: Analog Devices Inc
• Type: Class Dr

Specifications of SSM2302CPZ-REEL

• Output Type: 2-Channel (Stereo)
• Max Output Power X Channels @ Load: 1.4W x 2 @ 8 Ohm
• Voltage - Supply: 2.5 V ~ 5 V
• Features: Depop, Differential Inputs, Short-Circuit and Thermal Protection, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 16-LFCSP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: SSM2302Z-EVAL - BOARD EVAL FOR SSM2302
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

LAYOUT
As output power continues to increase, care needs to be taken to
lay out PCB traces and wires properly between the amplifier,
load, and power supply. A good practice is to use short, wide
PCB tracks to decrease voltage drops and minimize inductance.
Make track widths at least 200 mil for every inch of track length
for lowest DCR, and use 1 oz or 2 oz of copper PCB traces to
further reduce IR drops and inductance. A poor layout
increases voltage drops, consequently affecting efficiency. Use
large traces for the power supply inputs and amplifier outputs to
minimize losses due to parasitic trace resistance. Proper
grounding guidelines helps to improve audio performance,
minimize crosstalk between channels, and prevent switching
noise from coupling into the audio signal. To maintain high
output swing and high peak output power, the PCB traces that
connect the output pins to the load and supply pins should be as
wide as possible to maintain the minimum trace resistances. It
is also recommended to use a large-area ground plane for
minimum impedances. Good PCB layouts also isolate critical
analog paths from sources of high interference. High frequency
circuits (analog and digital) should be separated from low
frequency ones. Properly designed multilayer printed circuit
boards can reduce EMI emission and increase immunity to RF
field by a factor of 10 or more compared with double-sided
boards. A multilayer board allows a complete layer to be used
for ground plane, whereas the ground plane side of a double-
side board is often disrupted with signal crossover. If the system
has separate analog and digital ground and power planes, the
analog ground plane should be underneath the analog power
plane, and, similarly, the digital ground plane should be
underneath the digital power plane. There should be no overlap
between analog and digital ground planes nor analog and
digital power planes.
Rev. 0 | Page 13 of 20
INPUT CAPACITOR SELECTION
The SSM2302 will not require input coupling capacitors if the
input signal is biased from 1.0 V to V
capacitors are required if the input signal is not biased within
this recommended input dc common-mode voltage range, if
high-pass filtering is needed (Figure 20), or if using a single-
ended source (Figure 21). If high-pass filtering is needed at the
input, the input capacitor along with the input resistor of the
SSM2302 will form a high-pass filter whose corner frequency is
determined by the following equation:
Input capacitor can have very important effects on the circuit
performance. Not using input capacitors degrades the output
offset of the amplifier as well as the PSRR performance.
PROPER POWER SUPPLY DECOUPLING
To ensure high efficiency, low total harmonic distortion (THD),
and high PSRR, proper power supply decoupling is necessary.
Noise transients on the power supply lines are short-duration
voltage spikes. Although the actual switching frequency can
range from 10 kHz to 100 kHz, these spikes can contain
frequency components that extend into the hundreds of
megahertz. The power supply input needs to be decoupled with
a good quality low ESL and low ESR capacitor—usually around
4.7 μF. This capacitor bypasses low frequency noises to the
ground plane. For high frequency transients noises, use a 0.1 μF
capacitor as close as possible to the VDD pin of the device.
Placing the decoupling capacitor as close as possible to the
SSM2302 helps maintain efficiency performance.
f
C
= 1/(2π × R
IN
× C
IN
)
DD
− 1.0 V. Input
SSM2302