SSM2211CPZ-REEL Analog Devices Inc, SSM2211CPZ-REEL Datasheet - Page 20

• Manufacturer Part Number: SSM2211CPZ-REEL
• Description: IC,Audio Amplifier,SINGLE,CMOS,LLCC,8PIN,PLASTIC
• Manufacturer: Analog Devices Inc
• Type: Class ABr

Specifications of SSM2211CPZ-REEL

• Output Type: 1-Channel (Mono)
• Max Output Power X Channels @ Load: 1.5W x 1 @ 4 Ohm
• Voltage - Supply: 2.7 V ~ 5.5 V
• Features: Differential Inputs, Shutdown
• Mounting Type: Surface Mount
• Package / Case: 8-LFCSP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

SSM2211
The polarity of the speakers is important because each output is
180° out of phase with the other. By connecting the negative
terminal of Speaker 1 to Pin 5 and the positive terminal of
Speaker 2 to Pin 8, proper speaker phase can be established.
The maximum power dissipation of the device, assuming both
loads are equal, can be found by doubling Equation 11. If the
loads are different, use Equation 11 to find the power dissipa-
tion caused by each load, and then take the sum to find the total
power dissipated by the SSM2211.
EVALUATION BOARD
An evaluation board for the SSM2211 is available. For more
information, call 1-800-ANALOGD.
AUDIO
The voltage gain of the SSM2211 is given by Equation 20.
If desired, the input signal can be attenuated by turning the
10 kΩ potentiometer in the CW (clockwise) direction. C
isolates the input common-mode voltage (V
Pin 2 and Pin 3. With V+ = 5 V, there is a 2.5 V common-mode
voltage present at both output terminals, V
Caution: The ground lead of the oscilloscope probe, or any
other instrument used to measure the output signal, must not
be connected to either output because this shorts out one of the
amplifier outputs and may damage the device.
A safe method of displaying the differential output signal using
a grounded scope is shown in Figure 51. Connect Channel A
probe to the V
the V
together. Most multichannel oscilloscopes have this feature built
in. If you must connect the ground lead of the test instrument
to either of the output signal pins, a power-line isolation
transformer must be used to isolate the instrument ground
from the power supply ground.
INPUT
20kΩ POT.
VOLUME
A
OUT
V
A post. Invert Channel B, and add the two channels
SHUTDOWN
= 2
×
OUT
CW
R
R
ON
Figure 50. Evaluation Board Schematic
F
I
B terminal post. Connect Channel B probe to
C
1µF
IN
+
20kΩ
R
I
51kΩ
R1
1
2
3
4
SSM2211
20kΩ
0.1µF
R
V+
C1
F
6
7
OUT
+
8
5
C2
10µF
A and V
DD
J1
J2
/2) present at
C1
0.1µF
OUT
R
1W 8Ω
B, as well.
L
IN
V
V
OUT
OUT
(20)
Rev. E | Page 20 of 24
B
A
Recall that
Therefore, for P
8 V p­p. If the available input signal is 1.4 V rms or more, use
the PCB as is, with R
increase the value of R
When the closed-loop gain required by your source level is
determined, it can develop 1 W across the 8 Ω load resistor with
the normal input signal level, replace the resistor with a speaker.
The speaker can be connected across the V
for bridged-mode operation only after the 8 Ω load resistor is
removed. For no phase inversion, V
the positive (+) terminal of the speaker.
To use the SSM2211 in a single-ended-output configuration,
replace J1 and J2 jumpers with electrolytic capacitors of a suitable
value, with the negative terminals to the output Terminal V
and Terminal V
to ground. Note that the maximum output power is reduced to
250 mW (one-quarter of the rated maximum), due to the maxi-
mum swing in the nonbridged mode being one-half and power
being proportional to the square of the voltage. For frequency
response down to 3 dB at 100 Hz, a 200 μF capacitor is required
with 8 Ω speakers.
The SSM2211 evaluation board also comes with a shutdown
switch, which allows the user to switch between on (normal
operation) and the power-conserving shutdown mode.
LFCSP PCB CONSIDERATIONS
The LFCSP is a plastic encapsulated package with a copper lead
frame substrate. This is a leadless package with solder lands on
the bottom surface of the package, instead of conventional
formed perimeter leads. A key feature that allows the user to
reach the quoted θ
paddle (DAP) on the bottom surface of the package. When
soldered to the PCB, the DAP can provide efficient conduction
of heat from the die to the PCB. To achieve optimum package
performance, consideration should be given to the PCB pad
design for both the solder lands and the DAP. For further
information, the user is directed to the Amkor Technology
document, Application Notes for Surface Mount Assembly of
Amkor’s MicroLead Frame (MLF) Packages. This can be
downloaded from the Amkor Technology website.
SSM2211
Figure 51. Using an Oscilloscope to Display the Bridged-Output Voltage
V
=
P
5
COMMON
8
MODE
×
2.5V
OUT
OUT
R
JA
B. The single-ended loads can then be returned
= 1 W and R
performance is the exposed die attach
F
= R
F
.
8Ω
1W
I
= 20 kΩ. If more gain is needed,
V
V
GND
OUT
OUT
B
A
L
PROBES
= 8 Ω, V = 2.8 V rms or
OUT
B must be connected to
OUT
CH A
CH B
OSCILLOSCOPE
A and V
INV. ON
CH B
DISPLAY
OUT
A+B
B posts
OUT
A