AD7715

–13–

REV. C

AD7715-3

Table IX shows the AD7715-3 output rms noise for the selectable notch and –3 dB frequencies for the part, as selected by FS1 and

and are generated at an analog input voltage of 0 V with the part used in unbuffered mode (BUF bit of the Setup Register = 0).

Table X meanwhile shows the output peak-to-peak noise for the selectable notch and –3 dB frequencies for the part. It is important to

note that these numbers represent the resolution for which there will be no code flicker. They are not calculated based on rms noise but on peak-

0. These numbers are typical, are generated at an analog input voltage of 0 V and are rounded to the nearest LSB.

Meanwhile, Table XI and Table XII show rms noise and peak-to-peak resolution respectively with the AD7715-3 operating under

the same conditions as above except that now the part is operating in buffered mode (BUF Bit of the Setup Register = 1).

Table IX. Output RMS Noise vs. Gain and Output Update Rate for AD7715-3 (Unbuffered Mode)

Filter First Notch & O/P Data Rate

–3 dB Frequency

Typical Output RMS Noise in

V

MCLK IN =

MCLK IN =

MCLK IN =

MCLK IN =

2.4576 MHz

1 MHz

2.4576 MHz

1 MHz

GAIN = 1

GAIN = 2

GAIN = 32

GAIN = 128

50 Hz

20 Hz

13.1 Hz

5.24 Hz

3.0

1.7

0.7

0.65

60 Hz

25 Hz

15.72 Hz

6.55 Hz

3.4

2.1

0.7

0.7

250 Hz

100 Hz

65.5 Hz

26.2 Hz

45

20

2.2

1.6

500 Hz

200 Hz

131 Hz

52.4 Hz

270

135

9.7

3.3

Table X. Peak-to-Peak Resolution vs. Gain and Output Update Rate for AD7715-3 (Unbuffered Mode)

Filter First Notch & O/P Data Rate

–3 dB Frequency

Typical Peak-to-Peak Resolution in Bits

MCLK IN =

MCLK IN =

MCLK IN =

MCLK IN =

2.4576 MHz

1 MHz

2.4576 MHz

1 MHz

GAIN = 1

GAIN = 2

GAIN = 32

GAIN = 128

50 Hz

20 Hz

13.1 Hz

5.24 Hz

16

16

14

12

60 Hz

25 Hz

15.72 Hz

6.55 Hz

16

16

14

12

250 Hz

100 Hz

65.5 Hz

26.2 Hz

13

13

13

11

500 Hz

200 Hz

131 Hz

52.4 Hz

11

11

10

10

Table XI. Output RMS Noise vs. Gain and Output Update Rate for AD7715-3 (Buffered Mode)

Filter First Notch & O/P Data Rate

–3 dB Frequency

Typical Output RMS Noise in

V

MCLK IN =

MCLK IN =

MCLK IN =

MCLK IN =

2.4576 MHz

1 MHz

2.4576 MHz

1 MHz

GAIN = 1

GAIN = 2

GAIN = 32

GAIN = 128

50 Hz

20 Hz

13.1 Hz

5.24 Hz

4.5

2.4

0.9

0.9

60 Hz

25 Hz

15.72 Hz

6.55 Hz

5.1

2.9

0.9

1.0

250 Hz

100 Hz

65.5 Hz

26.2 Hz

50

25

2.6

2

500 Hz

200 Hz

131 Hz

52.4 Hz

270

135

9.7

3.3

Table XII. Peak-to-Peak Resolution vs. Gain and Output Update Rate for AD7715-3 (Buffered Mode)

Filter First Notch & O/P Data Rate

–3 dB Frequency

Typical Peak-to-Peak Resolution in Bits

MCLK IN =

MCLK IN =

MCLK IN =

MCLK IN =

2.4576 MHz

1 MHz

2.4576 MHz

1 MHz

GAIN = 1

GAIN = 2

GAIN = 32

GAIN = 128

50 Hz

20 Hz

13.1 Hz

5.24 Hz

16

16

14

12

60 Hz

25 Hz

15.72 Hz

6.55 Hz

16

16

14

12

250 Hz

100 Hz

65.5 Hz

26.2 Hz

13

13

12

11

500 Hz

200 Hz

131 Hz

52.4 Hz

10

11

10

10