FEATURES
Data Rate: 1.25MSPS
Signal-to-Noise Ratio: 93dB
Total Harmonic Distortion: −101dB
Spurious-Free Dynamic Range: 103dB
Linear Phase with 615kHz Bandwidth
Passband Ripple: ±0.0025dB
Adjustable FIFO Output Buffer (ADS1626 only)
Selectable On-Chip Reference
Directly Connects to TMS320C6000 DSPs
Adjustable Power Dissipation: 150 to 515mW
Power Down Mode
Supplies: Analog +5V
Digital +3V
Digital I/O +2.7V to +5.25V

APPLICATIONS
Scientific Instruments
Automated Test Equipment
Data Acquisition
Medical Imaging
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.