FEATURES
Monolithic 10-Bit/60 MSPS Converter
TTL Outputs
Bipolar (ⴞ1.75 V) Analog Input
56 dB SNR @ 2.3 MHz Input
Low (45 pF) Input Capacitance
MIL-STD-883-Compliant Versions Available
APPLICATIONS
Digital Oscilloscopes
Medical Imaging
Professional Video
Radar Warning/Guidance Systems
Infrared Systems
GENERAL DESCRIPTION
The AD9020 A/D converter is a 10-bit monolithic converter
capable of word rates of 60 MSPS and above. Innovative architecture using 512 input comparators instead of the traditional
1024 required by other flash converters reduces input capacitance and improves linearity.
Encode and outputs are TTL-compatible, making the AD9020
an ideal candidate for use in low power systems. An overflow bit is provided to indicate analog input signals greater
than +V
Voltage sense lines are provided to insure accurate driving of the
± V
REF
resistor ladder help optimize the integral linearity of the unit.
Either 68-pin ceramic leaded (gull wing) packages or ceramic
LCCs are available and are specifically designed for low thermal
impedances. Two performance grades for temperatures of both
0°C to 70°C and –55°C to +125°C ranges are offered to allow
the user to select the linearity best suited for each application.
Dynamic performance is fully characterized and production
tested at 25°C. MIL-STD-883 units are available.
The AD9020 A/D Converter is available in versions compliant
with MIL-STD-883. Refer to the Analog Devices Military Products Databook or current AD9020/883B data sheet for detailed
specifications.
.
SENSE
voltages applied to the units. Quarter-point taps on the
ANALOG IN
+V
REF
+V
SENSE
3/4
REF
1/2
REF
1/4
REF
–V
SENSE
–V
REF
ENCODE
A/D Converter
AD9020
FUNCTIONAL BLOCK DIAGRAM
MSB
C
O
M
P
A
R
A
T
O
R
L
A
T
C
H
E
S
INVERT
AD9020
OVERFLOW
1024
–V
S
LSBS
INVERT
D
E
C
O
D
E
L
O
G
I
C
+V
S
10
GROUND
L
A
T
C
H
R/2
R/2
R/2
R/2
R/2
R/2
R/2
OVERFLOW
512
R
385
384
R
R
257
256
R
R
129
128
R
R
2
R
1
R/2
OVERFLOW
D
(MSB)
9
D
8
D
7
D
6
D
5
D
4
D
3
D
2
D
1
D0 (LSB)
REV. C
Information furnished by Analog Devices is believed to be accurate and
reliable. However, no responsibility is assumed by Analog Devices for its
use, nor for any infringements of patents or other rights of third parties that
may result from its use. No license is granted by implication or otherwise
under any patent or patent rights of Analog Devices.
Logic “1” Voltage (I
Logic “0” Voltage (IOL = 6 mA)FullVI0.4V
POWER SUPPLY
Supply Current25°CI440530440530mA
+V
S
Supply Current25°CI140170140170mA
–V
S
Power Dissipation25°CI2.83.32.83.3W
Power Supply Rejection
Ratio (PSRR)
NOTES
1
Absolute maximum ratings are limiting values to be applied individually, and beyond which the service ability of the circuit may be impaired. Functional operability is
not necessarily implied. Exposure to absolute maximum rating conditions for an extended period of time may affect device reliability.
tested and not included in linearity specifications.
4
Measured with ANALOG IN = +V
5
Output delay measured as worst-case time from 50% point of the rising edge of ENCODE to 50% point of the slowest rising or falling edge of D0–D9. Output skew
measured as worst-case difference in output delay among D0–D9.
6
RMS signal to rms noise with analog input signal 1 dB below full scale at specified frequency.
7
Intermodulation measured with analog input frequencies of 2.3 MHz and 3.0 MHz at 7 dB below full scale.
8
Measured as the ratio of the worst-case change in transition voltage of a single comparator for a 5% change in +V
Specifications subject to change without notice.
, and 1/4
REF
7
= 2 mA)FullVI2.42.4V
OH
25°CV7070dBc
FullVI542542mA
FullVI177177mA
FullVI3.43.4W
8
reference ladder taps are driven from dc sources at +0.875 V, 0 V, and –0.875 V, respectively. Accuracy of the overflow comparator is not
REF
SENSE
FullVI610610mV/V
.
or –VS.
S
REV. C
–3–
AD9020
EXPLANATION OF TEST LEVELS
Test Level
I– 100% production tested.
II – 100% production tested at 25°C, and sample tested at
specified temperatures.
III – Sample tested only.
IV – Parameter is guaranteed by design and characterization
testing.
V – Parameter is a typical value only.
VI – All devices are 100% production tested at 25°C. 100%
production tested at temperature extremes for extended
temperature devices; sample tested at temperature extremes
for commercial/industrial devices.