ADS1625
ADS1626
SBAS280C − JUNE 2003 − REVISED JUNE 2004
18 Bit, 1.25MSPS
Analog to Digital 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
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.
APPLICATIONS
D
Scientific Instruments
D
Automated Test Equipment
D
Data Acquisition
D
Medical Imaging
D
Vibration Analysis
VREFP VREFN VMID
RBIAS VCAP
AVDD DVDD IOVDD
Reference and Bias Circuits
AINP
AINN
∆Σ
Modulator
Digital
Filter
I/O
Interface
PD
REFEN
RESET
CLK
CS
RD
DRDY
OTR
ADS1626 Only
FIFO
ADS1625
ADS1626
AGND
DGND
DOUT[17:0]
FIFO_LEV[2:0]
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
2003−2004, Texas Instruments Incorporated
www.ti.com
BURR-BROWN [ BURR-BROWN CORPORATION ]
