OPA890IDBV BURR-BROWN [Burr-Brown Corporation], OPA890IDBV Datasheet - Page 16

• Manufacturer Part Number: OPA890IDBV
• Description: Low-Power, Wideband, Voltage-Feedback OPERATIONAL AMPLIFIER with Disable
• Manufacturer: BURR-BROWN [Burr-Brown Corporation]

OPA890
SBOS369 – MAY 2007
16
Again, an additional resistor (50 , in this case) is
included directly in series with the noninverting input.
This minimum recommended value provides part of
the
noninverting input bias current. It is also used to form
a simple parasitic pole to roll off the frequency
response at very high frequencies ( > 500MHz) using
the input parasitic capacitance to form a bandlimiting
pole. The gain resistor (R
circuit a dc gain of +1, which puts the input dc bias
voltage (2.5V) at the output as well. The voltage can
swing to within 1.35V of either supply pin. Driving a
demanding 100
this characterization circuit. Higher swings are
possible using a lighter load.
Figure 47. AC-Coupled, G = +2, Single-Supply,
50 Source
V
I
W
dc
59W
0.1 F
Specification and Test Circuit
source
m
R
750W
698W
698W
0.1 F
50W
G
load to a midpoint bias is used in
m
resistance
+5V
OPA890
G
+V
) is ac-coupled, giving the
S
750W
R
F
0.1 F
matching
m
V
O
DIS
+
6.8 F
100W
m
Submit Documentation Feedback
for
V /2
S
the
MULTIPLYING DAC SINGLE-ENDED OUTPUT
TRANSIMPEDANCE AMPLIFIER
Multiplyings
such as the DAC7822, can make good use of the
low-power, high slew rate amplifier, OPA890.
The frequency response of the schematic shown in
Figure 48
Figure 49. OPA2890 (as DAC Transimpedance
DB0
DB1
DB2
DB3
DB4
DB5
DB6
DB7
DB8
DB9
DB10
DB11
Figure 48. DAC Transimpedance Amplifier
83
77
71
65
59
53
47
41
100k
DAC7822
+5V
V
Amplifier) Frequency Response
½
is shown in
DD
digital-to-analog
GND
I
I
V
OUT1
OUT2
R
R
REF
R
R
2_3
R
FB
1
2
3
1M
Figure
-5V
Frequency (Hz)
5.56kW
2.5pF
49.
converters
0.1 F
10M
OPA890
m
+7.5V
-2.5V
www.ti.com
0V
£
(DACs),
V
OUT
100M
V
£
OUT
5V