AD9058AJJ-REEL [ADI]

Dual 8-Bit 50 MSPS A/D Converter; 双路,8位50 MSPS A / D转换器
AD9058AJJ-REEL
型号: AD9058AJJ-REEL
厂家: ADI    ADI
描述:

Dual 8-Bit 50 MSPS A/D Converter
双路,8位50 MSPS A / D转换器

转换器 模数转换器
文件: 总11页 (文件大小:282K)
中文:  中文翻译
下载:  下载PDF数据表文档文件
Dual 8-Bit 50 MSPS  
A/D Converter  
a
AD9058  
FUNCTIONAL BLOCK DIAGRAM  
FEATURES  
2 Matched ADCs on Single Chip  
50 MSPS Conversion Speed  
On-Board Voltage Reference  
Low Power (<1 W)  
AD9058  
+V  
REF  
Low Input Capacitance (10 pF)  
65 V Power Supplies  
Flexible Input Range  
ENCODE  
8-BIT  
8
ANALOG-  
TO-DIGITAL  
CONVERTER  
A
A
IN  
APPLICATIONS  
–V  
REF  
Quadrature Demodulation for Communications  
Digital Oscilloscopes  
Electronic Warfare  
2V  
REF  
Radar  
+V  
REF  
ENCODE  
8
8-BIT  
ANALOG-  
TO-DIGITAL  
CONVERTER  
B
GENERAL DESCRIPTION  
A
IN  
The AD9058 combines two independent, high performance,  
8-bit analog-to-digital converters (ADCs) on a single monolithic  
IC. Combined with an optional on-board voltage reference,  
the AD9058 provides a cost-effective alternative for systems  
requiring two or more ADCs.  
–V  
REF  
Dynamic performance (SNR, ENOB) is optimized to provide  
up to 50 MSPS conversion rates. The unique architecture  
results in low input capacitance while maintaining high per-  
formance and low power (<0.5 W/channel). Digital inputs  
and outputs are TTL compatible.  
QUADRATURE RECEIVER  
G
8
8
Q
Performance has been optimized for an analog input of 2 V p-p  
( 1 V; 0 V to 2 V). Using the on-board 2 V voltage reference,  
the AD9058 can be set up for unipolar positive operation  
(0 V to 2 V). This internal voltage reference can drive  
both ADCs.  
AD9058  
RF  
LO  
90؇  
I
G
Commercial (0°C to 70°C) and military (–55°C to +125°C)  
temperature range parts are available. Parts are supplied in  
hermetic 48-lead DIP and 44-lead “J” lead packages.  
E
REV.  
Information furnished by Analog Devices is believed to be accurate and  
reliable. However, no responsibility is assumed by Analog Devices for its  
use, norforanyinfringementsofpatentsorotherrightsofthirdpartiesthat  
may result from its use. No license is granted by implication or otherwise  
under any patent or patent rights of Analog Devices. Trademarks and  
registered trademarks are the property of their respective companies.  
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A.  
Tel: 781/329-4700  
781/461-3113  
www.analog.com  
Analog Devices, Inc. All rights reserved.  
2012  
Fax:  
©
AD9058–SPECIFICATIONS  
[؎VS = ؎5 V; VREF = 2 V (internal); ENCODE = 40 MSPS; AIN = 0 V to 2 V; –VREF  
=
GROUND, unless otherwise noted.]1 All specifications apply to either of the two ADCs.  
ELECTRICAL CHARACTERISTICS  
Test  
AD9058AJD/AJJ  
AD9058AKD/AKJ  
Parameter  
Temp  
Level  
Min  
Typ  
Max  
Min  
Typ  
Max  
Unit  
RESOLUTION  
8
8
Bits  
DC ACCURACY  
Differential Nonlinearity  
25°C  
Full  
25°C  
Full  
I
VI  
I
VI  
VI  
0.25  
0.5  
0.65  
0.8  
1.3  
1.4  
0.25  
0.5  
0.5  
0.7  
1.0  
1.25  
LSB  
LSB  
LSB  
LSB  
Integral Nonlinearity  
No Missing Codes  
Full  
Guaranteed  
75  
Guaranteed  
75  
ANALOG INPUT  
Input Bias Current  
25°C  
Full  
25°C  
25°C  
25°C  
I
VI  
I
IV  
V
170  
340  
170  
340  
μA  
μA  
Input Resistance  
Input Capacitance  
Analog Bandwidth  
12  
28  
10  
175  
12  
28  
10  
175  
kΩ  
15  
15  
pF  
MHz  
REFERENCE INPUT  
Reference Ladder Resistance  
25°C  
Full  
Full  
25°C  
Full  
25°C  
Full  
Full  
I
120  
80  
170  
220  
270  
120  
80  
170  
220  
270  
Ω
VI  
V
I
VI  
I
VI  
V
Ω
Ladder Tempco  
Reference Ladder Offset  
(Top)  
Reference Ladder Offset  
(Bottom)  
0.45  
8
0.45  
8
Ω/°C  
mV  
mV  
mV  
mV  
μV/°C  
16  
24  
23  
33  
16  
24  
23  
33  
8
8
Offset Drift Coefficient  
50  
50  
INTERNAL VOLTAGE REFERENCE  
Reference Voltage  
25°C  
Full  
Full  
I
VI  
V
1.95  
1.90  
2.0  
150  
10  
2.20  
2.25  
1.95  
1.90  
2.0  
150  
10  
2.20  
2.25  
V
V
μV/°C  
Temperature Coefficient  
Power Supply Rejection  
Ratio (PSRR)  
25°C  
I
25  
25  
mV/V  
SWITCHING PERFORMANCE  
Maximum Conversion Rate2  
Aperture Delay (tA)  
Aperture Delay Matching  
Aperture Uncertainty (Jitter)  
Output Delay (Valid) (tV)2  
25°C  
25°C  
25°C  
25°C  
25°C  
Full  
25°C  
Full  
25°C  
I
50  
0.8  
0.2  
10  
8
16  
12  
–16  
1
50  
0.1  
60  
0.8  
0.2  
10  
8
16  
12  
–16  
1
MSPS  
ns  
ns  
ps, rms  
ns  
ps/°C  
ns  
ps/°C  
ns  
IV  
IV  
V
I
V
I
0.1  
1.5  
0 5  
1.5  
0.5  
5
Output Delay (tV) Tempco  
2
Propagation Delay (tPD  
)
19  
Propagation Delay (tPD) Tempco  
Output Time Skew  
V
V
ENCODE INPUT  
Logic “1” Voltage  
Logic “0” Voltage  
Logic “1” Current  
Logic “0” Current  
Input Capacitance  
Pulsewidth (High)  
Pulsewidth (Low)  
Full  
Full  
Full  
Full  
25°C  
25°C  
25°C  
VI  
VI  
VI  
VI  
V
I
I
2
2
V
V
μA  
μA  
pF  
ns  
ns  
0.8  
600  
1000  
0.8  
600  
1000  
5
8
8
5
8
8
–2–  
E
REV.  
AD9058  
Test  
Level Min  
AD9058AJD/AJJ  
AD9058AKD/AKJ  
Parameter  
Temp  
Typ  
Max Min  
Typ  
Max  
Unit  
DYNAMIC PERFORMANCE  
Transient Response  
25°C  
25°C  
V
V
2
2
2
2
ns  
ns  
Overvoltage Recovery Time  
Effective Number of Bits (ENOB)3  
Analog Input @ 2.3 MHz  
@ 10.3 MHz  
25°C  
25°C  
I
I
7.7  
7.4  
7.2  
7.1  
7.7  
7.4  
Bits  
Bits  
Signal-to-Noise Ratio3  
Analog Input @ 2.3 MHz  
@ 10.3 MHz  
25°C  
25°C  
I
I
48  
46  
45  
44  
48  
46  
dB  
dB  
Signal-to-Noise Ratio3 (Without Harmonics)  
Analog Input @ 2.3 MHz  
@ 10.3 MHz  
25°C  
25°C  
I
I
48  
47  
46  
45  
48  
47  
dB  
dB  
Second Harmonic Distortion  
Analog Input @ 2.3 MHz  
@ 10.3 MHz  
25°C  
25°C  
I
I
58  
58  
48  
48  
58  
58  
dBc  
dBc  
Third Harmonic Distortion  
Analog Input @ 2.3 MHz  
@ 10.3 MHz  
25°C  
25°C  
25°C  
I
I
IV  
58  
58  
60  
50  
50  
48  
58  
58  
60  
dBc  
dBc  
dBc  
Crosstalk Rejection4  
DIGITAL OUTPUTS  
Logic “1” Voltage (IOH = 2 mA)  
Logic “0” Voltage (IOL = 2 mA)  
Full  
Full  
VI  
VI  
2.4  
2.4  
V
V
0.4  
0.4  
POWER SUPPLY5  
+VS Supply Current  
–VS Supply Current  
Power Dissipation  
Full  
Full  
Full  
VI  
VI  
VI  
127  
27  
770  
154  
38  
960  
127  
27  
770  
154  
38  
960  
mA  
mA  
mW  
NOTES  
1For applications in which +VS may be applied before –VS, or +VS current is not limited to 500 mA, a reverse-biased clamping diode should be inserted between  
ground and –VS to prevent destructive latch up. See section entitled “Using the AD9058.”  
2To achieve guaranteed conversion rate, connect each data output to ground through a 2 kΩ pull-down resistor.  
3SNR performance limits for the 48-lead DIP “D” package are 1 dB less than shown. ENOB limits are degraded by 0.3 dB. SNR and ENOB measured with  
analog input signal 1 dB below full scale at specified frequency.  
4Crosstalk rejection measured with full-scale signals of different frequencies (2.3 MHz and 3.5 MHz) applied to each channel. With both signals synchronously  
encoded at 40 MSPS, isolation of the undesired frequency is measured with an FFT.  
5Applies to both A/Ss and includes internal ladder dissipation.  
Specifications subject to change without notice.  
E
–3–  
REV.  
AD9058  
ABSOLUTE MAXIMUM RATINGS1  
Analog Input . . . . . . . . . . . . . . . . . . . . . . . . –1.5 V to +2.5 V  
+VS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 V  
–VS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +0.8 V to –6 V2  
Digital Inputs . . . . . . . . . . . . . . . . . . . . . . . . . –0.5 V to +VS  
Digital Output Current . . . . . . . . . . . . . . . . . . . . . . . . 20 mA  
Voltage Reference Current . . . . . . . . . . . . . . . . . . . . . . 53 mA  
+VREF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.5 V  
–VREF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –1.5 V  
Operating Temperature Range  
AD9058AJD/AJJ/AKD/AKJ . . . . . . . . . . . . . . . 0°C to 70°C  
Maximum Junction Temperature3  
AD9058AJD/AJJ/AKD/AKJ . . . . . . . . . . . . . . . . . . . 150°C  
Storage Temperature Range . . . . . . . . . . . . –65°C to +150°C  
Lead Temperature (Soldering, 10 sec) . . . . . . . . . . . . . 300°C  
NOTES  
1Absolute 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.  
2For applications in which +VS may be applied before –VS, or +VS current is  
not limited to 500 mA, a reverse-biased clamping diode should be inserted  
between ground and –VS to prevent destructive latch up. See section entitled  
“Using the AD9058.”  
3Typical thermal impedances: 44-lead hermetic J-leaded ceramic package: θJA = 86.4°C/W;  
θ
JC = 24.9°C/W; 48-lead hermetic: DIP θJA = 40°C/W; θJC = 12°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.  
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.  
CAUTION  
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily  
accumulate on the human body and test equipment and can discharge without detection. Although  
the AD9058 features proprietary ESD protection circuitry, permanent damage may occur on  
devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are  
recommended to avoid performance degradation or loss of functionality.  
WARNING!  
ESD SENSITIVE DEVICE  
+V  
S
5V  
+V  
D –D *  
–V  
A
S
0
7
REF  
**  
13k  
+V  
IN  
INT  
ENCODE**  
+V  
REF  
+5V  
–5.2V  
+V  
S
COMP  
AD9058  
DIGITAL BITS  
ENCODE  
0.1F  
–V  
S
GROUND  
* INDICATES EACH PIN IS CONNECTEDTHROUGH 2k⍀  
** INDICATES EACH PIN IS CONNECTEDTHROUGH 100⍀  
Equivalent Encode Circuit  
–4–  
Burn-In Connections  
Equivalent Digital Outputs  
E
REV.  
AD9058  
PIN CONFIGURATIONS  
GROUND  
ENCODE  
1
2
3
4
5
6
7
8
9
48  
47  
46  
45  
44  
43  
42  
41  
D
D
D
D
D
D
D
D
(MSB)  
7
6
5
4
3
2
1
0
+V  
S
GROUND  
–V  
REF  
6
40  
–V  
S
NC  
7
39  
–V  
–V  
A
(LSB)  
S
IN  
S
+V  
S
40 GROUND  
39 –V  
–V  
–V  
REF  
REF  
GROUND 10  
+V 11  
COMP 12  
+V  
S
S
+V  
S
38 GROUND  
REF  
ENCODE  
ENCODE  
(MSB)  
AD9058  
TOP VIEW  
(Not to Scale)  
37 +V  
36 +V  
S
S
D
D
(MSB)  
7
7
AD9058  
+V  
13  
14  
INT  
D
6
D
D
6
TOPVIEW  
(Not to Scale)  
+V  
35 GROUND  
34 –V  
REF  
D
5
5
GROUND 15  
S
D
4
D
D
D
4
3
2
+V  
16  
17  
33 GROUND  
S
D
3
A
32  
31  
30  
29  
28  
27  
26  
25  
D
D
D
D
D
D
D
D
(LSB)  
IN  
0
1
2
3
4
5
6
7
D
2
NC 18  
GROUND  
D
1
D
1
19  
20  
–V  
S
17  
29  
–V  
REF  
28  
18  
GROUND 21  
+V 22  
S
ENCODE 23  
GROUND 24  
(MSB)  
NC = NO CONNECT  
NC = NO CONNECT  
AD9058AJJ/AKJ Pinouts  
AD9058AJD/AKD Pinouts  
PIN FUNCTION DESCRIPTIONS  
Function  
J-Lead  
Pin Number  
Ceramic DIP  
Pin Number  
ADC-A  
ADC-B  
Mnemonic  
ADC-A  
ADC-B  
3
4
5
6
7
8
9
43  
42  
41  
40  
39  
38  
37  
36  
35  
34–29  
28  
27  
26  
25  
24  
+VREF  
GROUND  
+VS  
AIN  
–VS  
Top of Internal Voltage Reference Ladder  
Analog Ground Return  
Positive 5 V Analog Supply Voltage  
Analog Input Voltage  
14  
15  
16  
17  
19  
20  
22  
23  
11  
10  
9
8
6
5
3
2
48  
47–42  
41  
1, 4, 40  
39  
38  
Negative 5 V Supply Voltage  
–VREF  
+VS  
Bottom of Internal Voltage Reference Ladder  
Positive 5 V Digital Supply Voltage  
TTL Compatible Convert Command  
Most Significant Bit of TTL Digital Output  
TTL Compatible Digital Output Bits  
Least Significant Bit of TTL Digital Output  
Digital Ground Return  
Negative 5 V Supply Voltage  
Analog Ground Return  
Positive 5 V Analog Supply Voltage  
10  
11  
12–17  
18  
19  
20  
21  
22  
ENCODE  
D7 (MSB)  
D6–D1  
D0 (LSB)  
GROUND  
–VS  
25  
26–31  
32  
21, 24, 33  
34  
35  
GROUND  
+VS  
36  
37  
COMMON PINS  
1
COMMON PINS  
12  
COMP  
+VINT  
Connection for External (0.1 μF)  
Compensation Capacitor  
Internal 2 V Reference; Can Drive  
+VREF for Both ADCs  
2
13  
E
–5–  
REV.  
AD9058  
THEORY OF OPERATION  
ANALOG IN  
128  
127  
The AD9058 contains two separate 8-bit analog-to-digital con-  
verters (ADCs) on a single silicon die. The two devices can be  
operated independently with separate analog inputs, voltage  
references, and clocks.  
+V  
REF  
In a traditional flash converter, 256 input comparators are required  
to make the parallel conversion for 8-bit resolution. This is in  
marked contrast to the scheme used in the AD9058, as shown  
in Figure 1.  
256  
8
8
2
1
Unlike traditional “flash,” or parallel, converters, each of the two  
ADCs in the AD9058 utilizes a patented interpolating archi-  
tecture to reduce circuit complexity, die size, and input capacitance.  
These advantages accrue because, compared to a conventional  
flash design, only half the normal number of input comparator  
cells is required to accomplish the conversion.  
–V  
REF  
Figure 1. Comparator Block Diagram  
In this unit, each of the two independent ADCs uses only 128 (27)  
comparators to make the conversion. The conversion for the  
seven most significant bits (MSBs) is performed by the 128  
comparators. The value of the least significant bit (LSB) is  
determined by interpolation between adjacent comparators in  
the decoding register. A proprietary decoding scheme processes  
the comparator outputs and provides an 8-bit code to the output  
register of each ADC; the scheme also minimizes error codes.  
Analog input range is established by the voltages applied at the  
voltage reference inputs (+VREF and –VREF). The AD9058 can  
operate from 0 V to 2 V using the internal voltage reference,  
or anywhere between –1 V and +2 V using external references.  
Input range is limited to 2 V p-p when using external references.  
The internal resistor ladder divides the applied voltage reference  
into 128 steps, with each step representing two 8-bit quanti-  
zation levels.  
1k  
ENCODE  
74HCT04  
10pF  
50⍀  
10  
36  
ENCODE  
A
ENCODE  
B
5, 9, 22,  
24, 37, 41  
8
–V  
+V  
S
REF A  
+5V  
400⍀  
38  
–V  
REF B  
18  
17  
16  
15  
14  
13  
12  
11  
D
(LSB)  
0A  
200⍀  
ANALOG  
IN A ؎0.5V  
5⍀  
6
A
AD9617  
IN A  
8
800⍀  
2
3
+V  
INT  
–2V  
AD707  
D
(MSB)  
(LSB)  
7A  
+2V  
20k⍀  
0.1F  
0.1F  
+V  
REF A  
CLOCK  
20k⍀  
28  
29  
30  
31  
32  
33  
34  
35  
D
0B  
43  
1
+V  
REF B  
800⍀  
400⍀  
8
COMP  
0.1F  
200⍀  
ANALOG  
IN B ؎0.5V  
5⍀  
40  
A
D
(MSB)  
AD9617  
IN B  
7B  
7, 20,  
CLOCK  
26, 39  
–5V  
1N4001  
AD9058  
(J-LEAD)  
–V  
S
(SEETEXT)  
0.1F  
4, 19, 21,  
25, 27, 42  
Figure 2. AD9058 Using Internal 2 V Voltage Reference  
–6–  
E
REV.  
AD9058  
1k  
ENCODE  
74ACT04  
+5V  
1
10pF  
50k⍀  
3
AD580  
2
10  
36  
10k⍀  
10k⍀  
ENCODE  
A
ENCODE  
B
+5V  
2N3904  
150⍀  
5, 9, 22,  
24, 37, 41  
1/2  
AD708  
+V  
S
+5V  
10⍀  
0.1F  
0.1F  
3
+V  
REF A  
RZ1  
20k⍀  
18  
17  
16  
15  
14  
13  
12  
11  
0.1F  
D
(LSB)  
43  
400⍀  
0A  
+V  
REF B  
ANALOG  
50⍀  
IN A  
5⍀  
؎1V  
؎0.125V  
8
AD9618  
A
IN A  
6
20k⍀  
150⍀  
D
(MSB)  
(LSB)  
7A  
10k⍀  
2N3906  
–5V  
8
CLOCK  
–V  
–V  
REF A  
1/2  
AD708  
RZ2  
28  
29  
30  
31  
32  
33  
34  
35  
0.1F  
D
0B  
38  
REF B  
–1V  
400⍀  
8
ANALOG  
IN B  
؎0.125V  
50⍀  
5k⍀  
؎1V  
A
AD9618  
IN B  
40  
D
(MSB)  
7B  
COMP  
7, 20,  
26, 39  
1
CLOCK  
0.1F  
–5V  
1N4001  
AD9058  
(J-LEAD)  
–V  
S
(SEETEXT)  
0.1F  
4, 19, 21,  
25, 27, 42  
Figure 3. AD9058 Using External Voltage References  
limited. If the negative supply is allowed to float (the +5 V supply  
is powered up before the –5 V supply), substantial +5 V supply  
current will attempt to flow through the substrate (VS supply con-  
tact) to ground. If this current is not limited to <500 mA, the part  
may be destroyed. The diode prevents this potentially destructive  
condition from occurring.  
The on-board voltage reference, +VINT, is a band gap reference  
that has sufficient drive capability for both reference ladders.  
It provides a 2 V reference that can drive both ADCs in the  
AD9058 for unipolar positive operation (0 V to 2 V).  
USING THE AD9058  
Refer to Figure 2. Using the internal voltage reference con-  
nected to both ADCs as shown reduces the number of external  
components required to create a complete data acquisition  
system. The input ranges of the ADCs are positive unipolar  
in this configuration, ranging from 0 V to 2 V. Bipolar input  
signals are buffered, amplified, and offset into the proper input  
range of the ADC using a good low distortion amplifier such  
as the AD9617 or AD9618.  
Timing  
Refer to the AD9058 Timing Diagram, Figure 4. The AD9058  
provides latched data outputs with no pipeline delay. To conserve  
power, the data outputs have relatively slow rise and fall times.  
When designing system timing, it is important to observe (1) setup  
and hold times; and (2) the intervals when data is changing.  
Figure 3 shows 2 kΩ pull-down resistors on each of the D0–D7  
output data bits. When operating at conversion rates higher than  
40 MSPS, these resistors help equalize rise and fall times and  
ease latching the output data into external latches. The 74ACT  
logic family devices have short setup and hold times and are the  
recommended choices for speeds of 40 MSPS or more.  
The AD9058 offers considerable flexibility in selecting the analog  
input ranges of the ADCs; the two independent ADCs can even  
have different input ranges if required. In Figure 3, the AD9058  
is shown configured for 1 V operation.  
The “Reference Ladder Offset” shown in the specifications table  
refers to the error between the voltage applied to the +VREF (top)  
or –VREF (bottom) of the reference ladder and the voltage required  
at the analog input to achieve a 1111 1111 or 0000 0000 transi-  
tion. This indicates the amount of adjustment range that must be  
designed into the reference circuit for the AD9058.  
Layout  
To ensure optimum performance, a single low impedance ground  
plane is recommended. Analog and digital grounds should be con-  
nected together and to the ground plane at the AD9058 device.  
Analog and digital power supplies should be bypassed to ground  
through 0.1 μF ceramic capacitors as close to the unit as possible.  
The diode shown between ground and –VS is normally reverse-  
biased and is used to prevent latch-up. Its use is recommended  
for applications in which power supply sequencing might allow  
+VS to be applied before –VS; or the +VS supply is not current  
For prototyping or evaluation, surface-mount sockets are available  
from Methode Electronics, Inc. (Part No. 213-0320602) for  
evaluating AD9058 surface-mount packages. To evaluate the  
E
–7–  
REV.  
AD9058  
AD9058 in through-hole PCB designs, use the AD9058AJD/AKD  
with individual pin sockets (AMP Part No. 6-330808-0). Alterna-  
tively, surface-mount AD9058 units can be mounted in a  
through-hole socket (Circuit Assembly Corporation, Irvine, Cali-  
fornia Part No. CA-44SPC-T).  
the time required for the AD9058 to achieve full accuracy when  
a step function input is applied. Overvoltage recovery time is the  
interval required for the AD9058 to recover to full accuracy after an  
overdriven analog input signal is reduced to its input range.  
Time domain performance of the ADC is also extremely important  
in digital oscilloscopes. When a track-/sample-and-hold is used  
ahead of the ADC, its operation becomes similar to that described  
above for receivers.  
AD9058 APPLICATIONS  
Combining two ADCs in a single package is an attractive alterna-  
tive in a variety of systems when cost, reliability, and space are  
important considerations. Different systems emphasize particular  
specifications, depending on how the part is used.  
The dynamic response to high frequency inputs can be described by  
the effective number of bits (ENOB). The effective number of  
bits is calculated with a sine wave curve fit and is expressed as:  
In high density digital radio communications, a pair of high  
speed ADCs are used to digitize the in-phase (I) and quadrature  
(Q) components of a modulated signal. The signal presented to  
each ADC in this type of system consists of message-dependent  
amplitudes varying at the symbol rate, which is equal to the  
sample rates of the converters.  
ENOB = N LOG2 Error measured Error ideal  
(
)
(
)
]
[
where N is the resolution (number of bits) and measured error is  
actual rms error calculated from the converter’s outputs with  
a pure sine wave applied as the input.  
Maximum conversion rate is defined as the encode (sample)  
rate at which SNR of the lowest frequency analog test signal  
drops no more than 3 dB below the guaranteed limit.  
N
ANALOG  
INPUT  
N+1  
tA  
N+2  
60  
+125 C  
ENCODE  
D –D  
55  
50  
45  
40  
35  
30  
+25 C  
tV  
–55 C  
VALID DATA  
FOR N–1  
VALID DATA  
FOR N  
VALID DATA  
FOR N+1  
0
7
tPD  
DATA  
CHANGING  
tA = APERTURETIME  
tV = DATA DELAY OF PRECEDING ENCODE  
tPD = OUTPUT PROPAGATION DELAY  
Figure 4. Timing Diagram  
Figure 5 shows what the analog input to the AD9058 would  
look like when observed relative to the sample clock. Signal-to-  
noise ratio (SNR), transient response, and sample rate are all  
critical specifications in digitizing this “eye pattern.”  
0.1  
1
10  
100  
INPUT FREQUENCY – MHz  
Figure 6. Harmonic Distortion vs. Analog Input Frequency  
ANALOG  
INPUT  
55  
50  
45  
40  
35  
30  
8.0  
7.2  
SAMPLE  
CLOCK  
+25 C AND +125 C  
Figure 5. I and Q Input Signals  
Receiver sensitivity is limited by the SNR of the system. For the  
ADC, SNR is measured in the frequency domain and calculated  
with a Fast Fourier Transform (FFT). The signal-to-noise ratio  
equals the ratio of the fundamental component of the signal  
(rms amplitude) to the rms level of the noise. Noise is the sum  
of all other spectral components, including harmonic distortion,  
but excluding dc.  
6.4  
5.5  
–55 C  
0.1  
1
10  
100  
INPUT FREQUENCY – MHz  
Although the signal being sampled does not have a significant  
slew rate at the instant it is encoded, dynamic performance of  
the ADC and the system is still critical. Transient response is  
Figure 7. Dynamic Performance vs. Analog Input  
Frequency  
–8–  
E
REV.  
AD9058  
MECHANICAL INFORMATION  
Die Dimensions . . . . . . . . . 106 mils × 108 mils × 15 ( 2) mils  
Pad Dimensions . . . . . . . . . . . . . . . . . . . . . . . . 4 mils × 4 mils  
Metallization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Gold  
Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . None  
Substrate Potential . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . –VS  
Passivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Nitride  
Die Attach . . . . . . . . . . . . . . . . . . . . Gold Eutectic (Ceramic)  
Bond Wire . . . . . . . . . 1 mil–1.3 mil, Gold; Gold Ball Bonding  
A
D
(LSB)  
IN  
0
+V  
GROUND  
S
–V  
S
GROUND  
+V  
GROUND  
REF  
+V  
S
COMP  
+VINT  
+V  
S
+V  
GROUND  
REF  
–V  
S
GROUND  
+V  
S
GROUND  
A
D (LSB)  
0
IN  
E
–9–  
REV.  
AD9058  
OUTLINE DIMENSIONS  
0.078 (1.98)  
0.040 (1.02)  
REF  
0.020 (0.51)  
REF  
45°  
0.662 (16.82)  
0.628 (15.95)  
0.054 (1.37)  
SQ  
45°  
0.025 (0.64)  
MIN  
3 PLACES  
39  
29  
40  
28  
0.032 (0.81)  
0.020 (0.51)  
PIN 1 INDEX  
0.065 (1.65)  
0.050  
(1.27)  
BSC  
0.650 (16.51)  
0.610 (15.49)  
PIN 1  
0.500 (12.70)  
0.492 (12.50)  
BOTTOM VIEW  
TOP VIEW  
0.023 (0.58)  
0.013 (0.33)  
6
18  
7
17  
0.700 (17.78)  
0.680 (17.27)  
SQ  
0.135 (3.43)  
0.100 (2.54)  
CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETERS DIMENSIONS  
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR  
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.  
44-Lead Ceramic Leaded Chip Carrier — J-Formed Leads [JLCC]  
(J-44)  
Dimensions shown in inches and (millimeters)  
0.098 (2.49)  
MAX  
0.005 (0.13)  
MIN  
48  
25  
0.620 (15.75)  
0.590 (14.99)  
PIN 1  
1
24  
0.630 (16.00)  
0.520 (13.21)  
0.225 (5.72)  
MAX  
2.424 (63.57) MAX  
0.060 (1.52)  
0.015 (0.38)  
0.150  
(3.81)  
MIN  
0.200 (5.08)  
0.125 (3.18)  
0.015 (0.38)  
0.008 (0.20)  
SEATING  
PLANE  
0.070 (1.78)  
0.030 (0.76)  
0.023 (0.58)  
0.014 (0.36)  
0.110 (2.79)  
0.090 (2.29)  
CONTROLLING DIMENSIONS ARE IN INCHES; MILLIMETER DIMENSIONS  
(IN PARENTHESES) ARE ROUNDED-OFF INCH EQUIVALENTS FOR  
REFERENCE ONLY AND ARE NOT APPROPRIATE FOR USE IN DESIGN.  
48-Lead Side-Brazed Ceramic Dual In-Line Package [SBDIP]  
(D-48)  
Dimensions shown in inches and (millimeters)  
ORDERING GUIDE  
Model1  
AD9058AJJ  
AD9058AJJ-REEL  
AD9058AKJ  
AD9058ATJ/883B  
AD9058AJD  
Temperature Range  
0°C to 70°C  
0°C to 70°C  
0°C to 70°C  
–55°C to +125°C  
0°C to 70°C  
Package Description  
44-Lead JLCC  
44-Lead JLCC  
44-Lead JLCC  
44-Lead JLCC  
48-Lead SBDIP  
48-Lead SBDIP  
48-Lead SBDIP  
Package Option2  
J-44  
J-44  
J-44  
J-44  
D-48  
D-48  
D-48  
AD9058AKD  
AD9058ATD/883B  
0°C to 70°C  
–55°C to +125°C  
1 For AD9058ATJ/883B and AD9058ATD/883B specifications, refer to Analog Devices Military Products Databook.  
2 D = Hermetic ceramic DIP package; J = leaded ceramic package.  
Rev. E | Page 10  
AD9058  
REVISION HISTORY  
9/12—Rev. D to Rev. E  
Changes to Mechanical Information Figure ................................. 9  
Changes to Outline Dimensions................................................... 10  
Changes to Ordering Guide .......................................................... 10  
5/03—Rev. C to Rev. D  
Changes to Ordering Guide ............................................................ 4  
Changes to Outline Dimensions................................................... 10  
6/01—Rev. B to Rev. C  
Edits to ELECTRICAL CHARACTERISTICS headings............. 2  
Edits to ABSOLUTE MAXIMUM RATINGS .............................. 4  
Edits to ORDERING GUIDE.......................................................... 4  
Edits to Pinout captions................................................................... 5  
Edits to Layout section..................................................................... 7  
©2012 Analog Devices, Inc. All rights reserved. Trademarks and  
registered trademarks are the property of their respective owners.  
D00562-0-9/12(E)  
Rev. E | Page 11  

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