NCS2211, NCV2211
http://onsemi.com
9
APPLICATIONS INFORMATION
The NCS2211 is unity gain stable and therefore does not
require any compensation, but a proper power−supply
bypass is required as shown in Figure 24. Performance will
be enhanced by adding a filter capacitor (C2) to the
mid−supply node (pin 2). See Typical Performance
Characteristics for details.
It is preferable to AC couple the input to avoid a large
DC output offset.
Both outputs can be driven to within 400 mV of either
supply rail with an 8 W load.
Typical Application of the Device:
6
Output (−)
VCC
Bias
(−) Input
Output (+)
Enable
−
+
−
+
R2
20k
R1
20k
C1
C2
0.1 mF
Figure 24.
+5 V
10 mF⎟⎟ 0.1 mF
C3
0.1 mF
2 V
PP
5
8
17
V
EE
2
4
3
Filtering
(+) Input
R
L
THERMAL CONSIDERATIONS
Care must be taken to not exceed the maximum junction
temperature of the device (150°C). Figure 15 shows the
tradeoff between output power and junction temperature for
different areas of exposed PCB copper (2 oz). If the
maximum power is exceeded momentarily, normal circuit
operation will be restored as soon as the die temperature is
reduced. Leaving the device in an “overheated” condition
for an extended period can result in device burnout. To
ensure proper operation, it is important to observe the SOA
curves.
GAIN
Since the output is differential, the gain from input to the
speaker is: A
VD
= 2 x R2/R1. For low level input signals,
THD will be optimized by pre−amplifying the signal and
running the NCS2211 at gain A
VD
= 2 and C2=1 mF.
BIAS FILTERING
Even though the NCS2211 will operate nominally with no
filter capacitor on pin 2, THD performance will be improved
dramatically with a filter capacitor installed (see Typical
Performance Characteristics). In addition a C2 filter
capacitor at pin 2 will suppress start−up popping noise. To
insure optimal suppression the time constant of the bias
filtering needs to be greater than the time constant of the
input capacitive coupling circuit, that is C2 x 25 k > C1 x R1.
ORDERING INFORMATION
Device Package Shipping
†
NCS2211DR2G
SOIC−8
(Pb−Free)
2500 / Tape & Reel
NCV2211DR2G*
NCS2211MNTXG DFN−8
(Pb−Free)
3000 / Tape & Reel
†For information on tape and reel specifications, including part orientation and tape sizes, please refer to our Tape and Reel Packaging
Specifications Brochure, BRD8011/D.
*NCV Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AEC−Q100 Qualified and PPAP
Capable.
