op183gbc Analog Devices, Inc., op183gbc Datasheet - Page 13

• Manufacturer Part Number: op183gbc
• Description: 5 Mhz Single-supply Operational Amplifiers
• Manufacturer: Analog Devices, Inc.

APPLICATIONS
OFFSET ADJUST
Figure 33 shows how the offset voltage of the OP183 can be
adjusted by connecting a potentiometer between Pins 1 and 5,
and connecting the wiper to V
the potentiometer is 10 kΩ. This will give an adjustment range
of approximately ±1 mV. If a larger adjustment span is desired, a
50 kΩ potentiometer will yield a range of ±2.5 mV.
PHASE REVERSAL
The OP183 is protected against phase reversal as long as both of
the inputs are within the range of the positive supply and the
negative supply −0.6 V. If there is a possibility of either input
going beyond these limits, however, the inputs should be
protected with a series resistor to limit input current to 2 mA.
DIRECT ACCESS ARRANGEMENT
The OP183 can be used in a single supply direct access
arrangement (DAA) as shown in Figure 34. This figure shows a
portion of a typical DAA capable of operating from a single 5 V
supply; with minor modifications it should also work on 3 V
supplies. Amplifiers A2 and A3 are configured so that the
transmit signal TxA is inverted by A2 and not inverted by A3.
Figure 33. OP183 Offset Adjust
3
2
OP183
1
V
CC
1
2
3
4
5
6
7
8
7
5
V
LL
DL
CK
DR
LR
DGND
VBR
L
EE
4
AD1868
V
. The recommended value for
EE
6
SERIAL
SERIAL
16-BIT
16-BIT
18-BIT
18-BIT
DAC
REG.
REG.
DAC
V
OS
V
V
REF
REF
AGND
VOR
VOL
VBL
Figure 35. 5 V Only 18-Bit Stereo DAC
V
S
16
15
14
13
12
11
10
9
Rev. D | Page 13 of 16
7.68kΩ
7.68kΩ
330pF
330pF
9.76kΩ
9.76kΩ
This arrangement drives the transformer differentially so that
the drive to the transformer is effectively doubled over a single
amplifier arrangement. This application takes advantage of the
ability of the OP183 to drive capacitive loads and to save power
in single-supply applications.
5 V ONLY STEREO DAC FOR MULTIMEDIA
The low noise and single-supply capability of the OP183 are
ideally suited for stereo DAC audio reproduction or sound
synthesis applications, such as multimedia systems. Figure 35
shows an 18-bit stereo DAC output setup that is powered from a
single 5 V supply. The low noise preserves the 18-bit dynamic
range of the AD1868.
3
2
6
5
OP183
OP183
7.68kΩ
7.68kΩ
2.5V
RxA
TxA
8
4
100pF
100pF
0.1μF
Figure 34. Direct Access Arrangement
REF
0.1μF
1
7
20kΩ
220μF
220μF
+
+
0.0047μF
–
–
750pF 20kΩ
A1
47kΩ
47kΩ
OP183
OP183
37.4kΩ
OP183
300pF
LEFT
CHANNEL
OUTPUT
RIGHT
CHANNEL
OUTPUT
22.1kΩ
3.3kΩ
20kΩ
A3
A2
20kΩ
20kΩ
0.33μF
475Ω
OP183