High Voltage, Differential
18-Bit ADC Driver
ADA4922-1
FUNCTIONAL BLOCK DIAGRAM
FEATURES
Single-ended-to-differential conversion
Low distortion (VO, dm = 40 V p-p)
−99 dBc HD at 100 kHz
ADA4922-1
8
1
NC
IN
Low differential output referred noise: 12 nV/√Hz
High input impedance: 11 MΩ
Fixed gain of 2
No external gain components required
Low output-referred offset voltage: 1.1 mV max
Low input bias current: 3.5 μA max
Wide supply range
2
3
7
6
5
REF
DIS
V
V
S+
S–
OUT+
4
OUT–
NC = NO CONNECT
5 V to 26 V
Figure 1.
Can produce differential output signals in excess of 40 V p-p
High speed
38 MHz, −3 dB bandwidth @ 0.2 V p-p differential output
Fast settling time
–84
–87
SECOND HARMONIC
THIRD HARMONIC
R
= 2kΩ
L
–90
200 ns to 0.01% for 12 V step on 5 V supplies
Disable feature
–93
–96
V
= ±5V, V
= 12V p-p
O, dm
S
Available in space-saving, thermally enhanced packages
3 mm × 3 mm LFCSP
8-lead SOIC_EP
–99
–102
–105
–108
–111
–114
–117
–120
Low supply current: IS = 10 mA on 12 V supplies
APPLICATIONS
V
= ±12V, V
= 40V p-p
100
S
O, dm
High voltage data acquisition systems
Industrial instrumentation
Spectrum analysis
1
10
FREQUENCY (kHz)
Figure 2. Harmonic Distortion for Various Power Supplies
ATE
Medical instruments
GENERAL DESCRIPTION
The ADA4922-1 is a differential driver for 16-bit to 18-bit
ADCs that have differential input ranges up to 2ꢀ ꢁ.
Configured as an easy-to-use, single-ended-to-differential
amplifier, the ADA4922-1 requires no external components to
drive ADCs. The ADA4922-1 provides essential benefits such as
low distortion and high SNR that are required for driving ADCs
with resolutions up to 18 bits.
The ADA4922-1 is manufactured on ADI’s proprietary second-
generation XFCB process that enables the amplifier to achieve
excellent noise and distortion performance on high supply
voltages.
The ADA4922-1 is available in an 8-lead 3 mm × 3 mm LFCSP
as well as an 8-lead SOIC package. Both packages are equipped
with an exposed paddle for more efficient heat transfer. The
ADA4922-1 is rated to work over the extended industrial
temperature range, −4ꢀ°C to +85°C.
With a wide supply voltage range (5 ꢁ to 26 ꢁ), high input
impedance, and fixed differential gain of 2, the ADA4922-1 is
designed to drive ADCs found to in a variety of applications,
including industrial instrumentation.
Rev. 0
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