WFD22 - 22 bit / 1 Msps Waveform digitizer

WFD22

  • 1 MHz sample rate with 22 bit resolution
  • Fully differential input with 10 ranges
  • 100MΩ low I-bias, 1MΩ Ultra-low noise input
  • 1.5ppm typical linearity
  • ±(25µV + 10ppm of range) absolute accuracy
  • Selectable filters to reduce out-of-band noise
  • -122dB THD typical (f-in=1kHz)
  • 105dB SNR typical (DC-500kHz)
  • Programmable DC-offset voltage
  • For ATX series hardware platform

The WFD22 is a 22 bit Waveform Digitizer for medium-speed / high resolution waveform capturing and analyzing. It combines superior dynamic performance with a very high DC accuracy.

The module features fully differential inputs to reduce common-mode level disturbances. It can also be used in Single Ended mode where an internal DC-offset source sets the midscale level. In this mode the negative input can be used as a GND Sense input, so the DC performance won’t be compromised due to ground currents.

The user can select between a 100MΩ low bias current input for highest absolute accuracy, or a 1MΩ ultra-low noise input for highest dynamic performance.

There are 10 input ranges from 0.425Vpp to 10.2Vpp, which allows easy adaptation to a wide range of Device Under Test output voltages.

A filter-bank with 3 Low Pass filters (40kHz, 250kHz and 500kHz) provides excellent signal conditioning resulting in lower noise and proper anti-aliasing.

Our proprietary technology combines four 20 bit ADCs to create an advanced 22 bit converter. This results in excellent SNR and linearity with a resolution down to 0.1µV. The large capture memory of 32M-word (96MB) allows capturing long waveforms. This can be very useful when a high number of averages is required.

All these features together result in the highest accuracy available when performing analog measurements. DAC linearity and dynamic performance measurements are a breeze with the WFD22 in the ATX7006 system.

Also applications like: Power meter testing, MRI amplifier test, Quantum effect research, etc. will benefit from the outstanding analog performance of the WFD22.

fft_10kHz_wfd22

DC to 500kHz spectrum, 10kHz carrier, no filtering

wfd22 block

(conditions: after 1 hour warm-up, TA=25ºC, filter bypass unless otherwise mentioned)

General

Resolution 22 bit
Sample rate 0 - 1MHz
Pattern depth 32M words

Input characteristics

Input impedance / mode 100MOhm low bias current mode / 1MOhm low noise mode
Input configuration Differential / Single Ended (-Input to Gnd, Gnd-sense or DC offset)
Input ranges (Vpp) 0.425, 0.637, 0.850, 1.275, 1.70, 2.55, 3.40, 5.10, 6.80, 10.20
Input filters Bypass, 40kHz (4-pole Butterw.), 250kHz (5-pole Butterworth), 500kHz (7-pole elliptic)
Bandwidth -3dB (typical) 1.1MHz (5.10Vpp range)
0.1dB flatness (typical) 200kHz (5.10Vpp range)
Input Common mode range +/- 10.2V

Accuracy (DC-offset off, 100ksps)

Absolute accuracy, ranges 1.70-10.2Vp ±(25µV + 10ppm of range)
Absolute accuracy, ranges 0.425-1.275Vp ±(25µV + 15ppm of range)
Non Linearity error ±3ppm of range (1.5ppm typical)
Input bias current (typical) 1pA in 100MOhm mode / 50nA in 1MOhm mode

DC-offset source

Resolution 20-bit (10µV)
Voltage range -5.1V to +5.1V
DC-offset accuracy ±(10µV + 6ppm of value)
Non Linearity ±3ppm of range

Dynamic characteristics

(conditions: 1MOhm input mode, 1Msps, 500kHz filter on)

SNR (5Vpp, 1kHz input) 99dB (105dB typical)
SNR (5Vpp, 10kHz input) 97dB
SNR (5Vpp, 100kHz input) 93dB
SNR (1kHz input, A-weighted) 110dB (BW 20Hz - 20kHz)
THD (5Vpp, 1kHz input) -115dB (-122dB typical)
THD (5Vpp, 10kHz input) -110dB
THD (5Vpp, 100kHz input) -94dB
SFDR (5Vpp, 1kHz input) 112 dB
CMRR (typical) 110 dB

Clock & Trigger inputs

Input impedance > 1MOhm
Threshold level 3.3V CMOS/TTL (5V tolerant)