Document
ADS1625 ADS1626
SBAS280E − JUNE 2003 − REVISED MAY 2007
18ĆBit, 1.25MSPS AnalogĆtoĆDigital Converter
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 are 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.
VREFP VREFN VMID RBIAS VCAP AVDD DVDD IOVDD
Reference and Bias Circuits
AINP AINN
∆Σ Modulator
Digital Filter
ADS1625 ADS1626
I/O Interface
ADS1626 Only FIFO
PD REFEN RESET CLK CS RD DRDY OTR
DOUT[17:0]
FIFO_LEV[2:0]
AGND
DGND
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. 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.
Copyright 2003−2007, Texas Instruments Incorporated
www.ti.com
ADS1625 ADS1626
SBAS280E − JUNE 2003 − REVISED MAY 2007
www.ti.com
ORDERING INFORMATION
PRODUCT
PACKAGE−LEAD
PACKAGE DESIGNATOR(1)
SPECIFIED TEMPERATURE
RANGE
PACKAGE MARKING
ORDERING NUMBER
ADS1625
HTQFP−64
ADS1625IPAPT
PAP
−40°C to +85°C
ADS1625I
ADS1625IPAPR
ADS1626
HTQFP−64
ADS1626IPAPT
PAP
−40°C to +85°C
ADS1626I
ADS1626IPAPR
(1) For the most current specifications and package information, refer to our web site at www.ti.com.
TRANSPORT MEDIA, QUANTITY
Tape and Reel, 250 Tape and Reel, 1000 Tape and Reel, 250 Tape and Reel, 1000
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
ADS1605
16 Bits
ADS1606
16 Bits
ADS1625
18 Bits
ADS1626
18 Bits
DATA RATE 5.0MSPS 5.0MSPS 1.25MSPS 1.25MSPS
FIFO? No Yes No 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.