OP213EP AD [Analog Devices], OP213EP Datasheet - Page 8

• Manufacturer Part Number: OP213EP
• Description: Low Noise, Low Drift Single-Supply Operational Amplifiers
• Manufacturer: AD [Analog Devices]

SoundPort is a registered trademark of Analog Device, Inc.
OP113/OP213/OP413
Low Voltage Headphone Amplifiers
Figure 9 shows a stereo headphone output amplifier for the
AD1849 16-bit SoundPort
reference voltage is derived from the common-mode voltage
generated internally by the AD1849, thus providing a conve-
nient bias for the headphone output amplifiers.
Low Noise Microphone Amplifier for Multimedia
The OP113 family is ideally suited as a low noise microphone
preamp for low voltage audio applications. Figure 10 shows a
gain of 100 stereo preamp for the AD1849 16-bit SoundPort
Stereo Codec chip. The common-mode output buffer serves as
a “phantom power” driver for the microphones.
CONDENSER
CONDENSER
AD1849
LOUT1R
LOUT1L
CMOUT
Figure 9. Headphone Output Amplifier for Multimedia
Sound Codec
Figure 10. Low Noise Stereo Microphone Amplifier for
Multimedia Sound Codec
ELECTRET
ELECTRET
INPUT
RIGHT
INPUT
LEFT
MIC
19
31
29
MIC
V
REF
10 F
10 F
10k
10k
V
REF
R VOLUME
CONTROL
OPTIONAL
L VOLUME
CONTROL
GAIN
1k
20
20
1k
10 F
10 F
V
REF
OP213
+5V
OPTIONAL
GAIN
1/2
®
OP213
OP213
Stereo Codec device. The pseudo-
50
50
1/2
1/2
OP213
5k
+5V
+5V
10k
10k
5k
1/2
100
16
16
OP213
100
1/2
10k
220 F
220 F
47k
OP213
+
+
47k
1/2
10k
+5V
HEADPHONE
LEFT
HEADPHONE
RIGHT
17
19
15
AD1849
MINL
CMOUT
MINR
–8–
Precision Voltage Comparator
With its PNP inputs and zero volt common-mode capability, the
OP113 family can make useful voltage comparators. There is
only a slight penalty in speed in comparison to IC comparators.
However, the significant advantage is its voltage accuracy. For
example, V
with CMRR and PSRR exceeding 100 dB, while operating on
5 V supply. Standard comparators like the 111/311 family oper-
ate on 5 volts, but not with common-mode at ground, nor with
offset below 3 mV. Indeed, no commercially available single
supply comparator has a V
Figure 11 shows the OP113 family response to a 10 mV over-
drive signal when operating in open loop. The top trace shows
the output rising edge has a 15 s propagation delay, while the
bottom trace shows a 7 s delay on the output falling edge. This
ac response is quite acceptable in many applications.
The low noise and 250 V (maximum) offset voltage enhance
the overall dc accuracy of this type of comparator. Note that
zero crossing detectors and similar ground referred comparisons
can be implemented even if the input swings to –0.3 volts below
ground.
0V
OS
t
r =
100
90
+2.5V
0%
can be a few hundred microvolts or less, combined
10
Figure 11. Precision Comparator
t
f = 5ms
–2.5V
2V
2V
OS
10mV OVERDRIVE
25k
less than 200 V.
100
5 s
OP113
1/2
+5V
REV. C