AD7490 Analog Devices, AD7490 Datasheet - Page 8

• Manufacturer Part Number: AD7490
• Description: 16-Channel, 1MSPS, 12-Bit ADC with Sequencer in 28-Lead TSSOP
• Manufacturer: Analog Devices

Specifications of AD7490

• Resolution (bits): 12bit
• # Chan: 16
• Sample Rate: 1MSPS
• Interface: Ser,SPI
• Analog Input Type: SE-Uni
• Ain Range: Uni (Vref),Uni (Vref) x 2
• Adc Architecture: SAR
• Pkg Type: CSP,SOP

AD7490
TYPICAL PERFORMANCE CHARACTERISTICS
Figure 5 shows a typical FFT plot for the AD7490 at 1 MSPS sample rate and 50 kHz input frequency.
Figure 7 shows the power supply rejection ratio vs. supply ripple frequency for the AD7490. The power supply rejection ratio is defined as
the ratio of the power in the ADC output at full-scale frequency f, to the power of a 200 mV p-p sine wave applied to the ADC V
of frequency f
where:
Pf is equal to the power at frequency f in ADC output.
Pf
Here, a 200 mV p-p sine wave is coupled onto the V
was used on the REF
S
is equal to power at frequency f
PSRR
–15
–35
–55
–75
–95
75
70
65
60
55
5
10
0
f
T
RANGE = 0V TO REF
S
( )
A
dB
= MAX THROUGHPUT
= 25°C
50
S
Figure 6. SINAD vs. Analog Input Frequency
.
Figure 5. Dynamic Performance at 1 MSPS
=
for Various Supply Voltages at 1 MSPS
10
100
×
IN
log
150
pin.
INPUT FREQUENCY (kHz)
⎛
⎜
⎜
⎝
IN
FREQUENCY (kHz)
Pf
Pf
200
s
⎞
⎟
⎟
⎠
100
250
S
coupled onto the ADC V
300
V
V
V
DD
V
DD
8192 POINT FFT
f
f
SINAD = 70.697dB
THD = –79.171dB
SFDR = –79.93dB
DD
350
SAMPLE
IN
DD
= V
= V
= V
= 50kHZ
= V
DRIVE
DRIVE
DRIVE
400
DRIVE
= 1MSPS
= 5.25V
= 2.7V
= 3.6V
= 4.75V
450
DD
supply. 10 nF decoupling was used on the supply, and a 1 μF decoupling capacitor
1000
500
Rev. C | Page 8 of 28
DD
supply input.
–50
–55
–60
–65
–70
–75
–80
–85
–90
–20
–30
–40
–50
–60
–70
–80
–90
10
0
V
200mV p-p SINE WAVE ON V
REF
T
f
T
RANGE = 0V TO REF
S
A
A
DD
= MAX THROUGHPUT
= 25°C
= 25°C
100k 200k 300k 400k 500k 600k 700k 800k 900k
IN
= 3V/5V, 10nF CAP
Figure 7. PSRR vs. Supply Ripple Frequency
Figure 8. THD vs. Analog Input Frequency
= 2.5V, 1µF CAP
for Various Supply Voltages at 1 MSPS
INPUT FREQUENCY (kHz)
INPUT FREQUENCY (Hz)
IN
DD
100
V
V
DD
DD
= 5V
= 3V
V
V
V
V
DD
DD
DD
DD
= V
= V
= V
= V
DRIVE
DRIVE
DRIVE
DRIVE
= 2.7V
= 3.6V
= 4.75V
= 5.25V
DD
1000
1M
supply