1FEATURES
2• High Speed:
– Data Rate: 1.25MSPS
– Bandwidth: 615kHz
• Outstanding Performance:
– SNR: 92dB at f IN = 100kHz, –1dBFS
– THD: –103dB at fIN = 100kHz, –6dBFS
– SFDR: 105dB at fIN = 100kHz, –6dBFS
• Ease-of-Use:
– High-Speed 3-Wire Serial Interface
– Directly Connects to TMS320 DSPs
– On-Chip Digital Filter Simplifies Anti-Alias
Requirements
– Simple Pin-Driven Control—No On-Chip
Registers to Program
– Selectable On-Chip Voltage Reference
– Simultaneous Sampling with Multiple
ADS1601s
• Low Power:
– 330mW at 1.25MSPS
– 145mW at 625kSPS
– Power-Down Mode

APPLICATIONS
• Sonar
• Vibration Analysis
• Data Acquisition

DESCRIPTION
The ADS1601 is a high-speed, high-precision,
delta-sigma analog-to-digital converter (ADC)
manufactured on an advanced CMOS process. The
ADS1601 oversampling topology reduces clock jitter
sensitivity during the sampling of high-frequency,
large amplitude signals by a factor of four over that
achieved by Nyquist-rate ADCs. Consequently,
signal-to-noise ratio (SNR) is particularly improved.
Total harmonic distortion (THD) is –103dB, and the
spurious-free dynamic range (SFDR) is 105dB
Optimized for power and performance, the ADS1601
dissipates only 330mW while providing a full-scale differential input range of ±0.94VREF. Having such a
wide input range makes out-of-range signals
uncommon. The OTR pin indicates if an analog input
out-of-range condition does occur. The differential
input signal is measured against the differential
reference, which can be generated internally on the
ADS1601 or supplied externally.
The ADS1601 uses an inherently stable advanced
modulator with an on-chip decimation filter. The filter
stop band extends to 19.3MHz, which greatly
simplifies the anti-aliasing circuitry. The modulator
samples the input signal up to 20MSPS, depending
on fCLK, while the 16x decimation filter uses a series
of four half-band FIR filter stages to provide 75dB of
stop band attenuation and 0.001dB of passband
ripple.
Output data is provided over a simple 3-wire serial
interface at rates up to 1.25MSPS, with a –3dB
bandwidth of 615kHz. The output data or its
complementary format directly connects to DSPs
such as TI’s TMS320 family, FPGAs, or ASICs. A
dedicated synchronization pin enables simultaneous
sampling with multiple ADS1601s in multi-channel
systems. Power dissipation is set by an external
resistor that allows a reduction in dissipation when
operating at slower speeds. All of the ADS1601
features are controlled by dedicated I/O pins, which
simplify operation by eliminating the need for on-chip
registers.
The high performing, easy-to-use ADS1601 is
especially suitable for demanding measurement
applications in sonar, vibration analysis, and data
acquisition. The ADS1601 is offered in a small, 7mm
× 7mm TQFP-48 package and is specified
from –40°C to +85°C.