Dual, 16 MHz, Rail-to-Rail
FET Input Amplifier
AD823
Data Sheet
CONNECTION DIAGRAM
OUT1 1
An offset voltage of 800 µV maximum, an offset voltage drift of
2 µV/°C, input bias currents below 25 pA, and low input voltage
noise provide dc precision with source impedances up to a
Gigaohm. It provides 16 MHz, −3 dB bandwidth, −108 dB THD
@ 20 kHz, and a 22 V/µs slew rate with a low supply current of
2.6 mA per amplifier. The AD823 drives up to 500 pF of direct
capacitive load as a follower and provides an output current of
15 mA, 0.5 V from the supply rails. This allows the amplifier to
handle a wide range of load conditions.
OUT2
6
–IN2
–VS 4
5
+IN2
AD823
Figure 1. 8-Lead PDIP and SOIC
RL = 100kΩ
CL = 50pF
+VS = +3V
G = +1
3V
500mV
00901-002
GND
200µs
Figure 2. Output Swing, +VS = +3 V, G = +1
Battery-powered precision instrumentation
Photodiode preamps
Active filters
12-bit to 16-bit data acquisition systems
Medical instrumentation
2
1
+VS = +5V
G = +1
0
–1
OUTPUT (dB)
The AD823 is a dual precision, 16 MHz, JFET input op amp
that can operate from a single supply of 3.0 V to 36 V or from
dual supplies of ±1.5 V to ±18 V. It has true single-supply
capability with an input voltage range extending below ground
in single-supply mode. Output voltage swing extends to within
50 mV of each rail for IOUT ≤ 100 µA, providing outstanding
output dynamic range.
+VS
7
+IN1 3
APPLICATIONS
GENERAL DESCRIPTION
8
–IN1 2
–2
–3
–4
–5
–6
–7
–8
1k
10k
100k
1M
FREQUENCY (Hz)
10M
00901-003
Single-supply operation
Output swings rail-to-rail
Input voltage range extends below ground
Single-supply capability from 3 V to 36 V
High load drive
Capacitive load drive of 500 pF, G = +1
Output current of 15 mA, 0.5 V from supplies
Excellent ac performance on 2.6 mA/amplifier
−3 dB bandwidth of 16 MHz, G = +1
350 ns settling time to 0.01% (2 V step)
Slew rate of 22 V/µs
Good dc performance
800 µV maximum input offset voltage
2 µV/°C offset voltage drift
25 pA maximum input bias current
Low distortion: −108 dBc worst harmonic @ 20 kHz
Low noise: 16 nV/√Hz @ 10 kHz
No phase inversion with inputs to the supply rails
00901-001
FEATURES
Figure 3. Small Signal Bandwidth, G = +1
This combination of ac and dc performance, plus the outstanding
load drive capability, results in an exceptionally versatile amplifier for applications such as A/D drivers, high speed active
filters, and other low voltage, high dynamic range systems.
The AD823 is available over the industrial temperature range of
−40°C to +85°C and is offered in both 8-lead PDIP and 8-lead
SOIC packages.
Rev. E
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