AD7992BRM-1 Analog Devices Inc, AD7992BRM-1 Datasheet - Page 15

• Manufacturer Part Number: AD7992BRM-1
• Description: IC ADC 12BIT 2CHAN I2C 10MSOP
• Manufacturer: Analog Devices Inc

Specifications of AD7992BRM-1

• Number Of Bits: 12
• Sampling Rate (per Second): 79k
• Data Interface: I²C, Serial
• Number Of Converters: 1
• Power Dissipation (max): 2.2mW
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 125°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP (0.118", 3.00mm Width)
• For Use With: EVAL-AD7992CB - BOARD EVALUATION FOR AD7992
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

For ac applications, removing high frequency components from
the analog input signal is recommended by use of an RC band-
pass filter on the relevant analog input pin. In applications
where harmonic distortion and signal-to-noise ratio are critical,
the analog input should be driven from a low impedance
source. Large source impedances significantly affect the ac
performance of the ADC. This may necessitate the use of an
input buffer amplifier. The choice of the op amp is a function
of the particular application.
When no amplifier is used to drive the analog input, the source
impedance should be limited to low values. The maximum
source impedance depends on the amount of total harmonic
distortion (THD) that can be tolerated. THD increases as the
source impedance increases, and performance degrades.
Figure 22 shows the THD vs. the analog input signal frequency
when using supply voltages of 3 V ± 10% and 5 V ± 10%.
Figure 23 shows the THD vs. the analog input signal frequency
for different source impedances.
Rev. 0 | Page 15 of 28
–100
–100
–50
–55
–60
–65
–70
–75
–80
–85
–90
–95
–40
–50
–60
–70
–80
–90
1
1
Figure 22. THD vs. Analog Input Frequency for Various
Figure 23. THD vs. Analog Input Frequency for Various
Source Impedances for V
Supply Voltages, F
INPUT FREQUENCY (kHz)
INPUT FREQUENCY (kHz)
R
SOURCE
10
= 10 Ω
V
10
DD
S
DD
= 136 kSPS, Mode 1
R
= 5.5 V, 136 kSPS, Mode 1
SOURCE
V
= 5.5V
DD
= 3.3V
V
DD
V
= 50 Ω
DD
= 3.0V
R
= 4.5V
R
SOURCE
SOURCE
V
R
V
DD
SOURCE
V
V
V
REF
DD
REF
DD
= 2.7V
= 5.5V
= 2.5V
= 5.0V
= 2.5V
= 100 Ω
= 1k Ω
= 0 Ω
AD7992
100
100