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Электронный компонент: ADS1625I

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SBAS280C - JUNE 2003 - REVISED JUNE 2004
18 Bit, 1.25MSPS
Analog to Digital Converter
ADS1625
ADS1626
FEATURES
D
Data Rate: 1.25MSPS
D
Signal-to-Noise Ratio: 93dB
D
Total Harmonic Distortion: -101dB
D
Spurious-Free Dynamic Range: 103dB
D
Linear Phase with 615kHz Bandwidth
D
Passband Ripple:
0.0025dB
D
Adjustable FIFO Output Buffer (ADS1626 only)
D
Selectable On-Chip Reference
D
Directly Connects to TMS320C6000 DSPs
D
Adjustable Power Dissipation: 150 to 515mW
D
Power Down Mode
D
Supplies: Analog +5V
Digital +3V
Digital I/O +2.7V to +5.25V
APPLICATIONS
D
Scientific Instruments
D
Automated Test Equipment
D
Data Acquisition
D
Medical Imaging
D
Vibration Analysis
DESCRIPTION
The ADS1625 and ADS1626 are high-speed, high-precision,
delta-sigma analog-to-digital converters (ADCs) with 18-bit
resolution. The data rate is 1.25 mega samples per second
(MSPS), the bandwidth (-3dB) is 615kHz, and passband
ripple is less than
0.0025dB (to
550kHz). Both devices offer
the same outstanding performance at these speeds with a
signal-to-noise ratio up to 93dB, total harmonic distortion
down to -101dB, and a spurious-free dynamic range up to
103dB. The ADS1626 includes an adjustable first-in, first-out
buffer (FIFO) for the output data.
The input signal is measured against a voltage reference that
can be generated on-chip or supplied externally. The digital
output data is provided over a simple parallel interface that
easily connects to digital signal processors (DSPs). An
out-of-range monitor reports when the input range has been
exceeded. The ADS1625/6 operate from a +5V analog
supply (AVDD) and +3V digital supply (DVDD). The digital
I/O supply (IOVDD) operates from +2.7 to +5.25V, enabling
the digital interface to support a range of logic families. The
analog power dissipation is set by an external resistor and
can be reduced when operating at slower speeds. A
power-down mode, activated by a digital I/O pin, shuts down
all circuitry. The ADS1625/6 are offered in a TQFP-64
package using TI PowerPAD
technology.
The ADS1625 and ADS1626, along with their 16-bit,
5MSPS counterparts, the ADS1605 and ADS1606, are
well-suited for the demanding measurement requirements
of scientific instrumentation, automated test equipment,
data acquisition, and medical imaging.
REFEN
Reference and Bias Circuits
I/O
Interface
Digital
Filter
Modulator
VREFP VREFN
RBIAS
VMID
VCAP
AVDD DVDD IOVDD
DGND
AGND
AINP
AINN
PD
CLK
CS
RESET
RD
DRDY
DOUT[17:0]
FIFO_LEV[2:0]
OTR
ADS1626 Only
FIFO
ADS1625
ADS1626
PowerPAD is a trademark of Texas Instruments. All other trademarks are the property of their respective owners.
PRODUCTION DATA information is current as of publication date. Products
conform to specifications per the terms of Texas Instruments standard warranty.
Production processing does not necessarily include testing of all parameters.
www.ti.com
Copyright
2003-2004, Texas Instruments Incorporated
Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments
semiconductor products and disclaimers thereto appears at the end of this data sheet.
ADS1625
ADS1626
SBAS280C - JUNE 2003 - REVISED JUNE 2004
www.ti.com
2
ORDERING INFORMATION
PRODUCT
PACKAGE-LEAD
PACKAGE
DESIGNATOR(1)
SPECIFIED
TEMPERATURE
RANGE
PACKAGE
MARKING
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
ADS1625
TQFP-64
PAP
-40
C to +85
C
ADS1625I
ADS1625IPAPT
Tape and Reel, 250
ADS1625
TQFP-64
PowerPAD
PAP
-40
C to +85
C
ADS1625I
ADS1625IPAPR
Tape and Reel, 1000
ADS1626
TQFP-64
PAP
-40
C to +85
C
ADS1626I
ADS1626IPAPT
Tape and Reel, 250
ADS1626
TQFP-64
PowerPAD
PAP
-40
C to +85
C
ADS1626I
ADS1626IPAPR
Tape and Reel, 1000
(1) For the most current specifications and package information, refer to our web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted(1)
ADS1625/26
UNIT
AVDD to AGND
-0.3 to +6
V
DVDD to DGND
-0.3 to +3.6
V
IOVDD to DGND
-0.3 to +6
V
AGND to DGND
-0.3 to +0.3
V
Input Current
100, Momentary
mA
Input Current
10, Continuous
mA
Analog I/O to AGND
-0.3 to AVDD + 0.3
V
Digital I/O to DGND
-0.3 to IOVDD + 0.3
V
Maximum Junction Temperature
+150
C
Operating Temperature Range
-40 to +105
C
Storage Temperature Range
-60 to +150
C
Lead Temperature (soldering, 10s)
+260
C
(1) Stresses above these ratings may cause permanent damage.
Exposure to absolute maximum conditions for extended periods
may degrade device reliability. These are stress ratings only, and
functional operation of the device at these or any other conditions
beyond those specified is not implied.
PRODUCT FAMILY
PRODUCT
RESOLUTION
DATA RATE
FIFO?
ADS1605
16 Bits
5.0MSPS
No
ADS1606
16 Bits
5.0MSPS
Yes
ADS1625
18 Bits
1.25MSPS
No
ADS1626
18 Bits
1.25MSPS
Yes
This integrated circuit can be damaged by ESD.
Texas Instruments recommends that all integrated
circuits be handled with appropriate precautions.
Failure to observe proper handling and installation procedures can
cause damage.
ESD damage can range from subtle performance degradation to
complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes
could cause the device not to meet its published specifications.
ADS1625
ADS1626
SBAS280C - JUNE 2003 - REVISED JUNE 2004
www.ti.com
3
ELECTRICAL CHARACTERISTICS
All specifications at -40
C to +85
C, AVDD = 5V, DVDD = IOVDD = 3V, fCLK = 40MHz, External VREF = +3V, VCM = 2.0V, FIFO disabled, and
RBIAS = 37k
, unless otherwise noted.
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Analog Input
0dBFS
1.545VREF
V
Differential input voltage (VIN)
(AINP - AINN)
-2dBFS
1.227VREF
V
Differential input voltage (VIN)
(AINP - AINN)
-6dBFS
0.774VREF
V
-20dBFS
0.155VREF
V
Common-mode input voltage (VCM)
(AINP + AINN) / 2
2.0
V
Absolute input voltage
(AINP or AINN with respect to AGND)
0dBFS
-0.1
4.7
V
Absolute input voltage
(AINP or AINN with respect to AGND)
-2dBFS input and smaller
0.1
4.2
V
Dynamic Specifications
Data rate
1.25
f
CLK
40MHz
MSPS
fIN = 10kHz, -2dBFS
93
dB
fIN = 10kHz, -6dBFS
90
dB
fIN = 10kHz, -20dBFS
76
dB
fIN = 100kHz, -2dBFS
93
dB
Signal-to-noise ratio (SNR)
fIN = 100kHz, -6dBFS
90
dB
Signal-to-noise ratio (SNR)
fIN = 100kHz, -20dBFS
70
76
dB
fIN = 500kHz, -2dBFS
93
dB
fIN = 500kHz, -6dBFS
90
dB
fIN = 500kHz, -20dBFS
76
dB
fIN = 10kHz, -2dBFS
-101
dB
fIN = 10kHz, -6dBFS
-103
dB
fIN = 10kHz, -20dBFS
-96
dB
fIN = 100kHz, -2dBFS
-95
dB
Total harmonic distortion (THD)
fIN = 100kHz, -6dBFS
-101
dB
Total harmonic distortion (THD)
fIN = 100kHz, -20dBFS
-98
-90
dB
fIN = 500kHz, -2dBFS
-114
dB
fIN = 500kHz, -6dBFS
-110
dB
fIN = 500kHz, -20dBFS
-96
dB
fIN = 10kHz, -2dBFS
92
dB
fIN = 10kHz, -6dBFS
89
dB
fIN = 10kHz, -20dBFS
76
dB
fIN = 100kHz, -2dBFS
91
dB
Signal-to-noise and distortion (SINAD)
fIN = 100kHz, -6dBFS
89
dB
Signal-to-noise and distortion (SINAD)
fIN = 100kHz, -20dBFS
69
76
dB
fIN = 500kHz, -2dBFS
93
dB
fIN = 500kHz, -6dBFS
90
dB
fIN = 500kHz, -20dBFS
76
dB
ADS1625
ADS1626
SBAS280C - JUNE 2003 - REVISED JUNE 2004
www.ti.com
4
ELECTRICAL CHARACTERISTICS (continued)
All specifications at -40
C to +85
C, AVDD = 5V, DVDD = IOVDD = 3V, fCLK = 40MHz, External VREF = +3V, VCM = 2.0V, FIFO disabled, and
RBIAS = 37k
, unless otherwise noted.
PARAMETER
UNIT
MAX
TYP
MIN
TEST CONDITIONS
fIN = 10kHz, -2dBFS
104
dB
fIN = 10kHz, -6dBFS
106
dB
fIN = 10kHz, -20dBFS
99
dB
fIN = 100kHz, -2dBFS
97
dB
Spurious-free dynamic range (SFDR)
fIN = 100kHz, -6dBFS
103
dB
Spurious-free dynamic range (SFDR)
fIN = 100kHz, -20dBFS
92
102
dB
fIN = 500kHz, -2dBFS
120
dB
fIN = 500kHz, -6dBFS
113
dB
fIN = 500kHz, -20dBFS
99
dB
Intermodulation distortion (IMD)
f1 = 495kHz, -2dBFS
f = 505kHz, -2dBFS
-98
dB
Intermodulation distortion (IMD)
f1 = 495kHz, -2dBFS
f2 = 505kHz, -2dBFS
-98
dB
Aperture delay
4
ns
Digital Filter Characteristics
Pass band
0
550
f
CLK
40MHz
kHz
Pass band ripple
0.0025
dB
Pass band transition
-0.1dB attenuation
575
f
CLK
40MHz
kHz
Pass band transition
-3.0dB attenuation
615
f
CLK
40MHz
kHz
Stop band
0.7
f
CLK
40MHz
39.3
f
CLK
40MHz
MHz
Stop band attenuation
72
dB
Group delay
20.8
40MHz
f
CLK
s
Settling time
To
0.001%
36.8
40MHz
f
CLK
s
Static Specifications
Resolution
18
Bits
No missing codes
18
Bits
Input referred noise
1.5
LSB, rms
Integral nonlinearity
-2.0dBFS signal
3.5
LSB
Differential nonlinearity
0.5
LSB
Offset error
0.05
%FSR
Offset error drift
1
ppmFSR/
C
Gain error
0.25
%
Gain error drift
Excluding reference drift
10
ppm/
C
Common-mode rejection
at DC
75
dB
Power-supply rejection
at DC
65
dB
ADS1625
ADS1626
SBAS280C - JUNE 2003 - REVISED JUNE 2004
www.ti.com
5
ELECTRICAL CHARACTERISTICS (continued)
All specifications at -40
C to +85
C, AVDD = 5V, DVDD = IOVDD = 3V, fCLK = 40MHz, External VREF = +3V, VCM = 2.0V, FIFO disabled, and
RBIAS = 37k
, unless otherwise noted.
PARAMETER
UNIT
MAX
TYP
MIN
TEST CONDITIONS
Voltage Reference(1)
VREF = (VREFP - VREFN)
2.5
3.0
3.2
V
VREFP
3.75
4.0
4.25
V
VREFN
0.75
1.0
1.25
V
VMID
2.3
2.5
2.8
V
VREF drift
Internal reference (REFEN = low)
50
ppm/
C
Startup time
Internal reference (REFEN = low)
15
ms
Clock Input
Frequency (fCLK)
1
40
50
MHz
Duty Cycle
fCLK = 40MHz
45
55
%
Digital Input/Output
VIH
0.7 IOVDD
IOVDD
V
VIL
DGND
0.3 IOVDD
V
VOH
IOH = 50
A
0.8 IOVDD
V
VOL
IOL = 50
A
0.2 IOVDD
V
Input leakage
DGND < VDIGIN < IOVDD
10
A
Power-Supply Requirements
AVDD
4.75
5.25
V
DVDD
2.7
3.3
V
IOVDD
2.7
5.25
V
AVDD current (IAVDD)
REFEN = low
110
135
mA
AVDD current (IAVDD)
REFEN = high
85
105
mA
DVDD current (IDVDD)
27
35
mA
IOVDD current (IIOVDD)
IOVDD = 3V
3
5
mA
Power dissipation
AVDD = 5V, DVDD = 3V, IOVDD = 3V,
REFEN = high
515
645
mW
Power dissipation
PD = low, CLK disabled
5
mW
Temperature Range
Specified
-40
+85
C
Operating
-40
+105
C
Storage
-60
+150
C
Thermal Resistance,
q
JA
PowerPAD soldered to PCB with 2oz.
trace and copper pad.
25
C/W
q
JC
PowerPAD soldered to PCB with 2oz.
trace and copper pad.
0.5
C/W
(1) The specification limits for VREF, VREFP, VREFN, and VMID apply when using the internal or an external reference. The internal reference
voltages are bounded by the limits shown. When using an external reference, the limits indicate the allowable voltages that can be applied to the
reference pins.