a
FEATURES
Low Power: 940 mW
53 dB SNR @ 10 MHz A
IN
On-Chip T/H, Reference
CMOS-Compatible
2 V p-p Analog Input
Fully Characterized Dynamic Performance
APPLICATIONS
Ultrasound Medical Imaging
Digital Oscilloscopes
Professional Video
Digital Communications
Advanced Television (MUSE Decoders)
Instrumentation
ENCODE
A
IN
GND
T/H
10-Bit 40 MSPS
A/D Converter
AD9040A
FUNCTIONAL BLOCK DIAGRAM
AMP
ARRAY
T/H
V
OUT
BANDGAP
REFERENCE
5-BIT
ADC
6-BIT
ADC
V
REF
REF
AMP
ERROR
CORRECTION
BP
REF
DECODE
LOGIC
DECODE
LOGIC
AD9040A
10
GENERAL DESCRIPTION
PRODUCT HIGHLIGHTS
The AD9040A is a complete 10-bit monolithic sampling analog-
to-digital converter (ADC) with on-board track-and-hold and
reference. The unit is designed for low cost, high performance
applications and requires only an encode signal to achieve
40 MSPS sample rates with 10-bit resolution.
Digital inputs and outputs are CMOS compatible; the analog
input requires a signal of 2 V p-p amplitude. The two-step
architecture used in the AD9040A is optimized to provide the
best dynamic performance available while maintaining low
power requirements of only 940 mW typically; maximum dissi-
pation is 1.1 watt at 40 MSPS.
The signal-to-noise ratio (SNR), including harmonics, is 53 dB,
or 8.5 ENOB, when sampling an analog input of 10.3 MHz at
40 MSPS. Competitive devices perform at less than 7.5 ENOB
and require external references and larger input signals.
The AD9040A A/D converter is available as either a 28-lead
plastic DIP or a 28-lead SOIC. The two models operate over a
commercial temperature range of 0°C to +70°C. Contact the
factory regarding availability of ceramic military temperature
range devices.
1. CMOS compatible logic for direct interface to ASICs.
2. On-board T/H provides excellent high frequency perfor-
mance on analog inputs, critical for communications and
medical imaging applications.
3. High input impedance and 2 volt p-p input range reduce
need for external amplifiers.
4. Easy to use; no cumbersome external voltage references
required, allowing denser packing of ADCs for multichannel
applications.
5. Available in 28-lead plastic DIP and SOIC packages.
6. Evaluation board includes AD9040AJR, reconstruction
DAC, and latches. Space is available near the analog input
and digital outputs of the converter for additional circuits.
Order as part number AD9040A/PCB (schematic shown in
data sheet).
REV. B
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
which may result from its use. No license is granted by implication or
otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.
Tel: 781/329-4700
World Wide Web Site: http://www.analog.com
Fax: 781/326-8703
© Analog Devices, Inc., 1999
AD9040A–SPECIFICATIONS
= V = +5 V; –V = –5 V; internal reference: ENCODE = 40.5 MSPS unless
(+V
ELECTRICAL CHARACTERISTICS
Parameter (Conditions)
RESOLUTION
DC ACCURACY
Differential Nonlinearity
Integral Nonlinearity
No Missing Codes
Gain Error
Gain Tempco
1
ANALOG INPUT
Input Voltage Range
Input Offset Voltage
Input Bias Current
Input Resistance
Input Capacitance
Analog Bandwidth
BANDGAP REFERENCE
Output Voltage
Temperature Coefficient
1
SWITCHING PERFORMANCE
Maximum Conversion Rate
Minimum Conversion Rate
Aperture Delay (t
A
)
Aperture Uncertainty (Jitter)
Output Propagation Delay (t
PD
)
2
DYNAMIC PERFORMANCE
Transient Response
Overvoltage Recovery Time
Signal-to-Noise Ratio
3
f
IN
= 2.3 MHz
f
IN
= 10.3 MHz
Signal-to-Noise Ratio
3
(Without Harmonics)
f
IN
= 2.3 MHz
f
IN
= 10.3 MHz
Signal-to-Noise Ratio
3, 4
f
IN
= = 2.3 MHz
f
IN
= = 10.3 MHz
Signal-to-Noise Ratio
3, 4
(Without Harmonics)
f
IN
= 2.3 MHz
f
IN
= 10.3 MHz
2nd Harmonic Distortion
f
IN
= 2.3 MHz
f
IN
= 10.3 MHz
3rd Harmonic Distortion
f
IN
= 2.3 MHz
f
IN
= 10.3 MHz
Two-Tone Intermodulation
Distortion Rejections
Differential Phase
Differential Gain
+25°C
Full
+25°C
Full
Full
+25°C
Full
Full
+25°C
+25°C
Full
+25°C
Full
+25°C
+25°C
+25°C
Full
Full
+25°C
+25°C
+25°C
+25°C
+25°C
Full
+25°C
+25°C
+25°C
+25°C
I
VI
I
VI
VI
I
VI
V
V
I
VI
I
VI
I
V
V
VI
V
I
IV
V
V
I
IV
V
V
I
I
51
50
S
D
S
otherwise noted)
Test
Level
Min
AD9040AJN/JR
Typ
10
1.0
1.0
Guaranteed
±
0.5
±
70
2
±
2
7
200
350
5
48
2.6
2.0
2.5
2.0
2.5
±
1.5
±
2
Max
Units
Bits
LSB
LSB
LSB
LSB
% FS
% FS
ppm/°C
V p-p
mV
mV
µA
µA
kΩ
pF
MHz
V
ppm/°C
MSPS
MSPS
ns
ps, rms
ns
ns
ns
ns
dB
dB
Temp
±
25
±
30
15
25
2.4
±
40
40
2
1.9
7
10
10
7.5
6
12
14
25
40
54
53
+25°C
+25°C
+25°C
+25°C
I
I
I
I
52
51
52
51
55
54
56
55
dB
dB
dB
dB
+25°C
+25°C
+25°C
+25°C
+25°C
+25°C
+25°C
+25°C
+25°C
I
I
I
I
I
I
V
III
III
–2–
53
53
56
56
58
58
57
56
67
65
73
70
62
0.15
0.25
0.5
1.0
dB
dB
dBc
dBc
dBc
dBc
dBc
Degrees
%
REV. B
AD9040A
Parameter (Conditions)
ENCODE INPUT
Logic “1” Voltage
Logic “0” Voltage
Logic “1” Current
Logic “0” Current
Input Capacitance
Encode Pulsewidth (High) (t
EH
)
6
Encode Pulsewidth (Low) (t
EL
)
6
DIGITAL OUTPUTS
Logic “1” Voltage
Logic “0” Voltage
Output Coding
POWER SUPPLY
V
D
Supply Current
+V
S
Supply Current
–V
S
Supply Current
Power Dissipation
Power Supply
Rejection Ratio (PSRR)
7
Temp
Full
Full
Full
Full
+25°C
+25°C
+25°C
Full
Full
Test
Level
VI
VI
VI
VI
V
IV
IV
VI
VI
Min
4.0
1.0
±
1
±
1
14
10
10
4.95
0.05
Offset Binary
Full
Full
Full
Full
+25°C
VI
VI
VI
VI
I
ABSOLUTE MAXIMUM RATINGS
1
AD9040AJN/JR
Typ
Max
Units
V
V
µA
µA
pF
ns
ns
V
V
100
100
13
89
87
0.94
20
110
105
1.2
±
15
mA
mA
mA
W
mV/V
NOTES
1
“Gain Tempco” is for converter using internal reference; “Temperature
Coefficient” is for bandgap reference only.
2
Output propagation delay (t
PD
) is measured from the 50% point of the falling
edge of the encode command to the min/max voltage levels of the digital
outputs with 10 pF maximum loads.
3
RMS signal to rms noise with analog input signal 1 dB below full scale at
specified frequency.
4
ENCODE = 32 MSPS.
5
3rd order intermodulation measured with analog input frequencies of 2.3 MHz
and 2.4 MHz at 7 dB below full scale.
6
For rated performance at 40 MSPS, duty cycle of encode command should be
50%
±
10%.
7
Measured as the ratio of the change in offset voltage for a 5% change in +V
S
or –V
S
.
Specifications subject to change without notice.
±
V
S
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
±
7 V
V
D
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +7 V
ANALOG IN . . . . . . . . . . . . . . . . . . . . . . . . . . . . –V
S
to +V
S
DIGITAL INPUTS . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to +V
S
V
REF
Input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 V to +V
S
Digital Output Current . . . . . . . . . . . . . . . . . . . . . . . . . 20 mA
Operating Temperature
AD9040AJN/JR . . . . . . . . . . . . . . . . . . . . . . . . 0°C to +70°C
Storage Temperature . . . . . . . . . . . . . . . . . –65°C to +150°C
Maximum Junction Temperature
2
(JN/JR Suffixes) . . . +150°C
Lead Soldering Temp (10 sec) . . . . . . . . . . . . . . . . . . . +300°C
NOTES
1
Absolute maximum ratings are limiting values to be applied individually, and
beyond which the serviceability 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.
2
Typical thermal impedances (parts soldered to board):
N Package (Plastic DIP):
θ
JA
= 42°C/W;
θ
JC
= 10°C/W.
R Package (SOIC):
θ
JA
= 47°C/W;
θ
JC
= 10°C/W.
EXPLANATION OF TEST LEVELS
Test Level
I – 100% Production Tested.
II – 100% production tested at +25°C, and sample tested at
specified temperatures. AC testing done on sample basis.
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 military
temperature devices; guaranteed by design and character-
ization testing for industrial devices.
ORDERING GUIDE
Model
AD9040AJN
AD9040AJR
AD9040A/PWB
AD9040A/PCB
Temperature Range
Package Description
Package Option
N-28
R-28
0°C to +70°C
28-Lead Plastic DIP
0°C to +70°C
28-Lead SOIC Package
Printed Circuit Board (Only) of Evaluation Circuit
Complete Evaluation Board, Assembled and Tested,
Including AD9040AJR
–3–
REV. B
AD9040A
N
N+1
A
IN
MIN
TYP
1.9
10
10
7.5
10ns
100
100
12
MAX
t
A
ENCODE
#2
#3
t
A
t
EH
t
EL
t
PD
APERTURE DELAY
PULSEWIDTH HIGH
PULSEWIDTH LOW
OUTPUT PROP DELAY
t
EH
t
EL
t
PD
DIGITAL
OUTPUTS
N–3
N–2
N–1
Figure 1. Timing Diagram
PIN FUNCTION DESCRIPTIONS
–V
S 1
28
D0 (LSB)
27
D1
26
D2
25
D3
24
D4
Pin No.
1, 12, 21
2, 4, 11, 14, 22
3, 10
5
6
Name
–V
S
GND
+V
S
V
OUT
Function
GND
2
+V
S 3
GND
4
V
OUT 5
V
REF 6
BP
REF 7
ENCODE
9
+V
S 10
GND
11
–V
S 12
A
IN 13
GND
14
7
8
9
13
15
16
17–20
23
24–27
28
D1
D0 (LSB)
DIE LAYOUT AND MECHANICAL INFORMATION
Die Dimensions . . . . . . . . . . . . . . . . . 204
×
185
×
21 (± 1) mils
Pad Dimensions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
×
4 mils
Metalization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Aluminum
Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . None
Substrate Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .–V
S
Transistor Count . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5,070
Passivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Oxynitride
Die Attach (JN/JR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . Epoxy
Bond Wire (JN/JR) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gold
GND
–V
S
+V
S
5 V Power Supply
Ground
Analog +5 V Power Supply
Internal Bandgap Voltage
Reference (Nominally +2.5 V)
V
REF
Noninverting Input to Reference
Amplifier. Voltage reference for
ADC is connected here.
BP
REF
External Connection for (0.1
µF)
Reference Bypass Capacitor
NC
No Connection Internally
ENCODE Encode Clock Input to ADC.
Internal T/H placed in hold mode
(ADC is encoding) on rising edge.
A
IN
Noninverting Input to T/H
Amplifier
OR
Out-of-Range Condition Output.
Active high when analog input
exceeds input range of ADC by
1 LSB (<FS –1 LSB or >+FS
+ 1 LSB).
D9 (MSB) Most Significant Bit of ADC
Output; TTL/CMOS Compatible
D8–D5
Digital Output Bits of ADC; TTL/
CMOS Compatible
V
D
Digital +5 V Power Supply
D4–D1
Digital Output Bits of ADC;
TTL/CMOSL Compatible
D0 (LSB) Least Significant Bit of ADC
Output; TTL/CMOS Compatible
GND
TOP VIEW
22
(Not to Scale)
21
–V
S
NC
8
20
D5
19
D6
18
D7
17
D8
16
D9 (MSB)
15
OR
AD9040A
23
V
D
NC = NO CONNECT
PDIP and SOIC Pinouts
D9 (MSB)
GND
A
IN
D7
+V
S
D6
D5
–V
S
DGND
V
D
D4
D3
D2
BP
REF
V
REF
ENCODE
D8
OR
–V
S
GND
NC
V
OUT
GND
–4–
REV. B
AD9040A
DEFINITIONS OF SPECIFICATIONS
Maximum Conversion Rate
Analog Bandwidth
The analog input frequency at which the spectral power of the
fundamental frequency (as determined by FFT analysis) is
reduced by 3 dB.
Aperture Delay
The encode rate at which parametric testing is performed.
Output Propagation Delay
The delay between the 50% point of the falling edge of the
ENCODE command and the 1 V/4 V points of output data.
Overvoltage Recovery Time
The delay between the rising edge of the ENCODE command
and the instant at which the analog input is sampled.
Aperture Uncertainty (Jitter)
The amount of time required for the converter to recover to
10-bit accuracy after an analog input signal 150% of full scale is
reduced to the full-scale range of the converter.
Power Supply Rejection Ratio (PSRR)
The sample-to-sample variation in aperture delay.
Differential Gain
The percentage of amplitude change of a small high frequency
sine wave (3.58 MHz) superimposed on a low frequency signal
(15.734 kHz).
Differential Nonlinearity
The ratio of a change in input offset voltage to a change in
power supply voltage.
Signal-to-Noise Ratio (SNR)
The deviation of any code from an ideal 1 LSB step.
Differential Phase
The ratio of the rms signal amplitude to the rms value of
“noise,” which is defined as the sum of all other spectral com-
ponents, including harmonics but excluding dc, with an analog
input signal 1 dB below full scale.
Signal-to-Noise Ratio (Without Harmonics)
The phase change of a small high frequency sine wave (3.58 MHz)
superimposed on a low frequency signal (15.734 kHz).
Harmonic Distortion
The rms value of the fundamental divided by the rms value of
the harmonic.
Integral Nonlinearity
The ratio of the rms signal amplitude to the rms value of
“noise,” which is defined as the sum of all other spectral com-
ponents, excluding the first eight harmonics and dc, with an
analog input signal 1 dB below full scale.
Transient Response
The deviation of the transfer function from a reference line
measured in fractions of 1 LSB using a “best straight line” de-
termined by a least square curve fit.
Minimum Conversion Rate
The time required for the converter to achieve 10-bit accuracy
when a step function is applied to the analog input.
Two-Tone Intermodulation Distortion (IMD) Rejection
The encode rate at which the SNR of the lowest analog signal
frequency tested drops by no more than 3 dB below the guaran-
teed limit.
V
CC
V
CC
1k
1k
1k
1k
The ratio of the power of either of two input signals to the
power of the strongest third-order IMD signal.
V
CC
V
CC
V
REF
A
IN
2k
6.8k
1mA
V
SS
ANALOG INPUT
REFERENCE CIRCUIT
V
SS
BANDGAP OUTPUT
CMOS OUTPUT
1mA
GND
BP
REF
GND
GND
R
L
2.5k
R
L
V
OUT
D0-9
Figure 2. Equivalent Circuits
REV. B
–5–
京公网安备 11010802033920号
EEWORLD
