AD7707BR Analog Devices Inc, AD7707BR Datasheet - Page 47

• Manufacturer Part Number: AD7707BR
• Description: A/D Converter (A-D) IC
• Manufacturer: Analog Devices Inc

Specifications of AD7707BR

• Peak Reflow Compatible (260 C): No
• No. Of Bits: 16 Bit
• Leaded Process Compatible: No
• Mounting Type: Surface Mount
• Features: 3V/5V, 1mW, 2?Channel, 16?Bit
• Package / Case: 20-SOIC
• Rohs Status: RoHS non-compliant
• Number Of Bits: 16
• Sampling Rate (per Second): 500
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 1mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

OUTPUT NOISE FOR HIGH LEVEL INPUT CHANNEL, AIN3
5 V OPERATION
Specified high level input voltage ranges of ±10 V, ±5 V, 0 V to
+10 V, and 0 V to +5 V only utilize two gain different gain settings
(gains of 2 and 4) out of the eight possible settings available
within the PGA. Table 31 and Table 32 show what the high level
channel performance actually is over the complete range of gain
settings. Table 31 shows the AD7707 output rms noise and
peak-to-peak resolution for the selectable notch and −3 dB
frequencies for the part, as selected by FS0, FS1, and FS2 of the
clock register. The numbers are given for all input ranges with a
V
These numbers are typical and are generated at an analog input
voltage of 0 V for buffered mode of operation. Table 32
meanwhile shows the rms and peak-to-peak resolution for
buffered mode of operation. It is important to note that these
Table 31. AIN3, Output RMS Noise/Peak-to-Peak Resolution vs. Gain and Output Update Rate @ +5 V Unbuffered Mode
Filter First
Notch and
Output Data
Rate
MCLK IN = 2.4576 MHz
10 Hz
50 Hz
60 Hz
250 Hz
500 Hz
Table 32. AIN3, Output RMS Noise/Peak-to-Peak Resolution vs. Gain and Output Update Rate @ +5 V Buffered Mode
Filter First
Notch and
Output Data
Rate
MCLK IN = 2.4576 MHz
10 Hz
50 Hz
60 Hz
250 Hz
500 Hz
REF
of 2.5 V, HBIAS = 2.5 V, HICOM = AGND, and AV
−3 dB
Frequency
2.62 Hz
13.1 Hz
15.72 Hz
65.5 Hz
131 Hz
−3 dB
Frequency
2.62 Hz
13.1 Hz
15.72 Hz
65.5 Hz
131 Hz
Gain of 1
14.28 (16)
37.4 (16)
48.8 (16)
778 (12.5)
4716 (10.5)
Gain of 1
10.90 (16)
31.34 (16)
36.74 (16)
690 (13)
4679 (10)
Gain of 2
7.4 (16)
22.2 (16)
26.6 (16)
475 (13)
2423 (10.5)
Gain of 2
5.10 (16)
15.82 (16)
20.36 (16)
430 (13)
2350 (10)
Typical Output RMS Noise in μV (Peak-to-Peak Resolution)
DD
Typical Output RMS Noise in μV (Peak-to-Peak Resolution)
= 5 V.
Gain of 4
5.2 (16)
14.3 (16)
15.88 (16)
187 (13)
1097 (10.5)
Gain of 4
3.52 (16)
9.77 (16)
12.29 (16)
212 (13)
1287 (10)
Rev. B | Page 47 of 52
Gain of 8
3.35 (16)
8.7 (16)
10.17 (16)
98 (13)
551 (10.5)
Gain of 8
2.62 (16)
6.00 (16)
7.33 (16)
100 (13)
564 (10)
numbers represent the resolution for which there is no code
flicker. They are not calculated based on rms noise but on peak-
to-peak noise. The output noise comes from two sources. The
first is the electrical noise in the semiconductor devices (device
noise) used in the implementation of the modulator. Secondly,
when the analog input is converted into the digital domain,
quantization noise is added. The device noise is at a low level
and is independent of frequency. The quantization noise starts
at an even lower level but rises rapidly with increasing frequency
to become the dominant noise source. The numbers in Table 31
and Table 32 are given for the bipolar input ranges. For the
unipolar ranges, the rms noise numbers are the same as the
bipolar range, but the peak-to-peak resolution is now based on half
the signal range, which effectively means losing one bit of
resolution.
Gain of 16
2.34 (16)
5.12 (16)
5.84 (16)
42 (13)
294 (10)
Gain of 16
3.35 (16)
7.33 (15.5)
8.78 (15.5)
60 (12.5)
288 (10.5)
Gain of 32
2.34 (16)
5.36 (15)
5.65 (15)
30 (13)
137 (10)
Gain of 32
3.34 (15.5)
7.7 (14.5)
8.1 (14.5)
31.7 (12.5)
150 (10)
Gain of 64
2.34 (15)
4.84 (14)
5.1 (14)
18.5 (12)
73 (10)
Gain of 64
3.34 (15)
7.6 (13.5)
8.1 (13.5)
23 (12)
81 (10)
Gain of 128
2.30 (14)
4.75 (13)
5.3 (13)
13.8 (12)
53 (10)
Gain of 128
2.34 (14.5)
7.5 (12.5)
8.1 (12.5)
18.3 (11.5)
49 (10)
AD7707