Datasheet

REV. B
–2–
AD7840–SPECIFICATIONS
(V
DD
= +5 V 6 5%, V
SS
= –5 V 6 5%, AGND = DGND = O V, REF IN = +3 V, R
L
= 2 kV,
C
L
= 100 pF. All specifications T
MIN
to T
MAX
unless othewise noted.)
Parameter J, A
1
K, B
1
S
1
Units Test Conditions/Comments
DYNAMIC PERFORMANCE
2
Signal to Noise Ratio
3
(SNR) 76 78 76 dB min V
OUT
= 1 kHz Sine Wave, f
SAMPLE
= 100 kHz
Typically 82 dB at +25°C for 0 < V
OUT
< 20 kHz
4
Total Harmonic Distortion (THD) –78 –80 –78 dB max V
OUT
= 1 kHz Sine Wave, f
SAMPLE
= 100 kHz
Typically –84 dB at +25°C for 0 < V
OUT
< 20 kHz
4
Peak Harmonic or Spurious Noise –78 –80 –78 dB max V
OUT
= 1 kHz Sine Wave, f
SAMPLE
= 100 kHz
Typically –84 dB at +25°C for 0 < V
OUT
< 20 kHz
4
DC ACCURACY
Resolution 14 14 14 Bits
Integral Nonlinearity ±2 ±1 ±2 LSB max
Differential Nonlinearity ±0.9 ±0.9 ±0.9 LSB max Guaranteed Monotonic
Bipolar Zero Error ±10 ±10 ±10 LSB max
Positive Full Scale Error
5
±10 ±10 ±10 LSB max
Negative Full Scale Error
5
±10 ±10 ±10 LSB max
REFERENCE OUTPUT
6
REF OUT @ +25°C 2.99 2.99 2.99 V min
3.01 3.01 3.01 V max
REF OUT TC ±60 ±60 ±60 ppm/°C max
Reference Load Change
(∆REF OUT vs. ∆I) –1 –1 –1 mV max Reference Load Current Change (0–500 µA)
REFERENCE INPUT
Reference Input Range 2.85 2.85 2.85 V min 3 V ± 5%
3.15 3.15 3.15 V max
Input Current 50 50 50 µA max
LOGIC INPUTS
Input High Voltage, V
INH
2.4 2.4 2.4 V min V
DD
= 5 V ± 5%
Input Low Voltage, V
INL
0.8 0.8 0.8 V max V
DD
= 5 V ± 5%
Input Current, I
IN
±10 ±10 ±10 µA max V
IN
= 0 V to V
DD
Input Current (CS Input Only) ±10 ±10 ±10 µA max V
IN
=V
SS
to V
DD
Input Capacitance, C
IN
7
10 10 10 pF max
ANALOG OUTPUT
Output Voltage Range ±3 ±3 ±3 V nom
DC Output Impedance 0.1 0.1 0.1 Ω typ
Short-Circuit Current 20 20 20 mA typ
AC CHARACTERISTICS
7
Voltage Output Settling Time Settling Time to within ±1/2 LSB of Final Value
Positive Full-Scale Change 4 4 4 µs max Typically 2 µs
Negative Full-Scale Change 4 4 4 µs max Typically 2.5 µs
Digital-to-Analog Glitch Impulse 10 10 10 nV secs typ
Digital Feedthrough 2 2 2 nV secs typ
POWER REQUIREMENTS
V
DD
+5 +5 +5 V nom ±5% for Specified Performance
V
SS
–5 –5 –5 V nom ±5% for Specified Performance
I
DD
14 14 15 mA max Output Unloaded, SCLK = +5 V. Typically 10 mA
I
SS
6 6 7 mA max Output Unloaded, SCLK = +5 V. Typically 4 mA
Power Dissipation 100 100 110 mW max Typically 70 mW
NOTES
1
Temperature ranges are as follows: J, K Versions, 0°C to +70°C; A, B Versions, –25°C to +85°C; S Version, –55°C to +125°C.
2
V
OUT
(pk-pk) = ±3 V
3
SNR calculation includes distortion and noise components.
4
Using external sample-and-hold (see Testing the AD7840).
5
Measured with respect to REF IN and includes bipolar offset error.
6
For capacitive loads greater than 50 pF, a series resistor is required (see Internal Reference section).
7
Sample tested @ +25°C to ensure compliance.
Specifications subject to change without notice.