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.