AD7903 Dual Differential 16-Bit, 1 MSPS PulSAR 12.0 mW in QSOP

The AD7903 is a dual 16-bit, successive approximation, analog-to-digital converter (ADC) that operates from a single power supply, VDDx, per ADC. It contains two low power, high speed, 16-bit sampling ADCs and a versatile serial interface port. On the CNVx rising edge, the AD7903 samples the voltage difference between the INx+ and INx− pins. The voltages on these pins usually swing in opposite phases between 0 V and VREF. The externally applied reference voltage of the REFx pins (VREF) can be set independently from the supply voltage pins, VDDx. The power of the device scales linearly with throughput.

Using the SDIx inputs, the SPI-compatible serial interface can also daisy-chain multiple ADCs on a single 3-wire bus and provide an optional busy indicator. It is compatible with 1.8 V, 2.5 V, 3 V, or 5 V logic, using the separate VIOx supplies.

The AD7903 is available in a 20-lead QSOP package with operation specified from −40°C to +125°C.

APPLICATIONS

Battery-powered equipment
Communications
Automated test equipment (ATE)
Data acquisition
Medical instrumentation
Redundant measurement
Simultaneous sampling

Features and Benefits

16-bit resolution with no missing codes

Throughput: 1 MSPS

Low power dissipation
7.0 mW at 1 MSPS (V_DD1 and V_DD2 only)
12.0 mW at 1 MSPS (total)
140 µW at 10 kSPS

INL: ±0.5 LSB typical, ±2.0 LSB maximum

True differential analog input range: ±V_REF
0 V to V_REF with V_REF between 2.4 V to 5.1 V
Allows use of any input range
Easy to drive with the ADA4941-1

SINAD: 93.5 dB at 1 kHz

THD: −112 dB at 1 kHz

No pipeline delay

Single-supply 2.5 V operation with 1.8 V/2.5 V/3 V/5 V logic interface

Serial interface SPI/QSPI/MICROWIRE/DSP compatible

20-lead QSOP package

Wide operating temperature range: −40°C to +125°C

Data Sheets

Document	note
AD7903: Dual Differential 16-Bit, 1 MSPS PulSAR ADC 12.0 mW in QSOP Data Sheet (Rev. B)	PDF 870 kB

Application Notes

Document	note
AN-935: Designing an ADC Transformer-Coupled Front End (Rev. 0)	PDF 363 kB
AN-742: Frequency Domain Response of Switched-Capacitor ADCs (Rev. B)	PDF 401 kB
AN-931: Understanding PulSAR ADC Support Circuitry (Rev. 0)	PDF 299 kB