Datasheet

–2–
REV. 0
AD7894–SPECIFICATIONS
(V
DD
= +5 V ⴞ 5%, GND = 0 V, REF IN = +2.5 V. All specifications T
MIN
to T
MAX
unless
otherwise noted.)
Parameter A Versions
l
B Versions
1
Units Test Conditions/Comments
DYNAMIC PERFORMANCE
2
Signal to (Noise + Distortion) Ratio
3
@ +25°C 78 78 dB min f
IN
= 70 kHz Sine Wave, f
SAMPLE
= 160 kHz
T
MIN
to T
MAX
77 77 dB min See Figure 14
Total Harmonic Distortion (THD)
3
–86 –86 dB max f
IN
= 10 kHz Sine Wave, f
SAMPLE
= 160 kHz,
Typically –87 dB. See Figure 15
Peak Harmonic or Spurious Noise
3
–92 –92 dB typ f
IN
= 10 kHz Sine Wave, f
SAMPLE
= 160 kHz
Intermodulation Distortion (IMD)
3
fa = 9 kHz, fb = 9.5 kHz, f
SAMPLE
= 160 kHz
2nd Order Terms –92 –92 dB typ
3rd Order Terms –92 –92 dB typ
DC ACCURACY
Resolution 14 14 Bits
Minimum Resolution for Which
No Missing Codes Are Guaranteed 14 14 Bits
Relative Accuracy
3
±2 ±1.5 LSB max
Differential Nonlinearity
3
–1 to +1.5 –1 to +1.5 LSB max
AD7894-2
Positive Gain Error
3
±12 ±10 LSB max
Unipolar Offset Error ±8 ±6 LSB max
AD7894-10, AD7894-3 Only
Positive Gain Error
3
±8 ±6 LSB max
Negative Gain Error
3
±8 ±6 LSB max
Bipolar Zero Error ±10 ±8 LSB max
ANALOG INPUT
AD7894-10
Input Voltage Range ±10 ±10 V
Input Current 2 2 mA max See Analog Input Section
AD7894-3
Input Voltage Range ±2.5 ±2.5 V
Input Current 1.5 1.5 mA max See Analog Input Section
AD7894-2
Input Voltage Range 0 to +2.5 0 to +2.5 V
Input Current 500 500 nA max
REFERENCE INPUT
REF IN Input Voltage Range 2.375/2.625 2.375/2.625 V min/V max 2.5 V ± 5%
Input Current 1 1 µA max
Input Capacitance
4
10 10 pF max
LOGIC INPUTS
Input High Voltage, V
INH
2.4 2.4 V min V
DD
= 5 V ± 5%
Input Low Voltage, V
INL
0.8 0.8 V max V
DD
= 5 V ± 5%
Input Current, I
IN
±10 ±10 µA max V
IN
= 0 V to V
DD
Input Capacitance, C
IN
4
10 10 pF max
LOGIC OUTPUTS
Output High Voltage, V
OH
4.0 4.0 V min I
SOURCE
= 400 µA
Output Low Voltage, V
OL
0.4 0.4 V max I
SINK
= 1.6 mA
Output Coding
AD7894-10, AD7894-3 Twos Complement
AD7894-2 Straight (Natural) Binary
CONVERSION RATE
Conversion Time
Mode 1 Operation 5 5 µs max
Mode 2 Operation
5
10 10 µs max
Track/Hold Acquisition Time
3
0.35 0.35 µs max
SAMPLE AND HOLD
–3 dB Small Signal Bandwidth 7.5 7.5 MHz typ
Aperture Jitter 50 50 ps typ