Data Sheet
AD5940
Parameter
Symbol Min
Typ
Max
Unit
Test Conditions/Comments
ADC DYNAMIC PERFORMANCE
fIN = 20 kHz sine wave, fSAMPLE = 200 kSPS; using
AINx voltage input channels; PGA gain = 1.5
Signal-to-Noise Ratio
SNR
Includes distortion and noise components
PGA gain = 1, 1.5, and 2
PGA gain = 4
80
76
dB
dB
70
dB
dB
dB
dB
PGA gain = 9
Total Harmonic Distortion1
Peak Harmonic or Spurious Noise1
Channel to Channel Crosstalk1
Noise (RMS)4
THD
−84
−86
−86
Measured on adjacent channels
See
Table 2
µV rms
800
400
nV/√Hz
nV/√Hz
Chop on
Chop off
ADC INPUT
Input Voltage Ranges1
Input to ADC mux
Voltage applied to any input pin
Pseudo differential voltage between
0.2
2.1
V
V
VBIAS_CAP pin and analog input from ADC mux
−0.9
−0.9
−0.6
−0.3
−0.133
0.00005
+0.9
+0.9
+0.6
+0.3
+0.133
3000
V
V
V
V
V
µA
Gain = 1
Gain = 1.5
Gain = 2
Gain = 4
Gain = 9
Input Current Range1
Low power TIA and high speed TIA current
input channel ranges
Common Mode Range1
Leakage Current
0.2
−1.5
1.1
0.5
2.1
+1.5
V
nA
AIN0, AIN1, AIN2, AIN3/BUF_VREF1V82,
AIN4/LPF0, AIN6, CE0, RE0 and SE0
2
2
DE0 pin only
AIN0, AIN1, AIN2, AIN3, AIN4, AIN6, CE0, RE0,
SE0, and DE0
During ADC acquisition
3 programmable settings
Input Current1
−8
+8
nA
pF
Input Capacitance
Antialias Filter 3 dB Frequency Range
40
Mode 0
Mode 1
Mode 2
50
100
250
kHz
kHz
kHz
ADC Channel Switch Settling Time
Time delay required after switching ADC input
channel; excludes sinc3 settling time
Antialias Filter −3 dB Cutoff
Frequency
250 kHz1
100 kHz1
50 kHz1
20
40
60
µs
µs
µs
DISCRETE FOURIER TRANSFORM (DFT)-
BASED IMPEDANCE MEASUREMENTS1
With High Bandwidth Loop
For impedance (Z) of 1000 Ω (0.1% tolerant
resistor), excitation frequency = 0.1 Hz to 200 kHz,
sine amplitude = 10 mV rms, RTIA = 5 kΩ; RCAL
=
200 Ω;1% accurate tempco 5 ppm/°C; single DFT
measurement; DFT using 8192 ADC samples;
Hanning on; HSDACCON, Bits[8:1] = 0x1B for low
power mode and impedance measurements
≤80 kHz; HSDACCON, Bits[8:1] = 0x7 for high
power mode and impedance measurements
≥80 kHz
Accuracy
Magnitude
−1.25
−0.3
0.2
0.2
1
+1.25
+0.3
%
%
%
20 kHz to 200 kHz
10 Hz to 20 kHz
1 Hz to <10 Hz
Phase
0.1
Degrees
Rev. 0 | Page 7 of 130