Datasheet

5
®
ADS7818
TYPICAL PERFORMANCE CURVES (Cont.)
At T
A
= +25°C, V
CC
= +5V, f
SAMPLE
= 500kHz, f
CLK
= 16 • f
SAMPLE
, and internal +2.5V reference, unless otherwise specified.
POWER SUPPLY REJECTION
vs POWER SUPPLY RIPPLE FREQUENCY
1 10 100 1k 10k 100k 1M
Power Supply Ripple Frequency (Hz)
Power Supply Rejection (mV/V)
30
25
20
15
10
5
0
0
FREQUENCY SPECTRUM
(4096 Point FFT; f
IN
= 10.9kHz, –0.2dB)
0 25062.5 187.5125
Frequency (kHz)
Amplitude (dB)
–120
–100
–80
–60
–40
–20
0
FREQUENCY SPECTRUM
(4096 Point FFT; f
IN
= 102kHz, –0.2dB)
Amplitude (dB)
–100
–80
–60
–40
–20
0 25062.5 187.5125
Frequency (kHz)
–120
CHANGE IN FULL-SCALE ERROR
vs EXTERNAL REFERENCE VOLTAGE
2.32.0 2.52.1 2.2 2.4
External Reference Voltage (V)
Delta from V
REF
= 2.5V (mV)
–1.2
0.2
–0.4
–0.6
–0.8
–1.0
–0.2
0.0
CHANGE IN OFFSET
vs EXTERNAL REFERENCE VOLTAGE
2.51.9 3.12.1 2.3 2.7 2.9
External Reference Voltage (V)
Delta from V
REF
= 2.5V (mV)
–0.4
0.5
0.0
–0.1
–0.2
–0.3
0.1
0.2
0.3
0.4
PEAK-TO-PEAK NOISE
vs EXTERNAL REFERENCE VOLTAGE
2.32.0 2.52.1 2.2 2.4
External Reference Voltage (LSB)
Peak-to-Peak Noise (LSB)
0.40
0.70
0.65
0.60
0.55
0.50
0.45