AD7738BRU Analog Devices Inc, AD7738BRU Datasheet - Page 10

• Manufacturer Part Number: AD7738BRU
• Description: IC ADC 24BIT 8-CH 28-TSSOP
• Manufacturer: Analog Devices Inc

Specifications of AD7738BRU

• Rohs Status: RoHS non-compliant
• Number Of Bits: 24
• Sampling Rate (per Second): 15.4k
• Data Interface: DSP, MICROWIRE™, QSPI™, Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 100mW
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 105°C
• Mounting Type: Surface Mount
• Package / Case: 28-TSSOP (0.173", 4.40mm Width)
• For Use With: EVAL-AD7738EBZ - BOARD EVAL FOR AD7738

AD7738
CHOPPING DISABLED
The second mode, in which the AD7738 is configured with chopping disabled (CHOP = 0), provides faster conversion time while still
maintaining high resolution. Tables IV to VI show the –3 dB frequencies and typical performance versus channel conversion time or
equivalent output data rate, respectively. Table IV shows the typical output rms noise. Table V shows the typical effective resolution
based on the rms noise. Table VI shows the typical output peak-to-peak resolution, representing values for which there will be no code
flicker within a six-sigma limit. The peak-to-peak resolutions are not calculated based on rms noise, but on peak-to-peak noise.
These typical numbers are generated from 4096 data samples acquired in Continuous Conversion mode with an analog input voltage
set to 0 V and MCLK = 6.144 MHz. The Conversion Time is selected via the Channel Conversion Time register.
FW
127
92
35
16
9
8
3
FW
127
92
35
16
9
8
3
FW
127
92
35
16
9
8
3
Conversion Conversion Output
Time
Register
7Fh
5Ch
23h
10h
9h
8h
3h
Conversion Conversion Output
Time
Register
7Fh
5Ch
23h
10h
9h
8h
3h
Conversion Conversion Output
Time
Register
7Fh
5Ch
23h
10h
9h
8h
3h
Time
( s)
1357
992
398
200
127
117
65
Time
( s)
1357
992
398
200
127
117
65
Time
( s)
1357
992
398
200
127
117
65
Table IV. Typical Output RMS Noise in V vs. Conversion Time and Input Range with
Chopping Disabled
Table V. Typical RMS Resolution in Bits vs. Conversion Time and Input Range with
Chopping Disabled
Table VI. Typical Peak-to-Peak Resolution in Bits vs. Conversion Time and Input Range with
Chopping Disabled
Data Rate
(Hz)
737
1008
2511
4991
7847
8545
15398
Data Rate
(Hz)
737
1008
2511
4991
7847
8545
15398
Data Rate
(Hz)
737
1008
2511
4991
7847
8545
15398
–3 dB
Frequency
(Hz)
671
917
2285
2510
7141
7776
14013
–3 dB
Frequency
(Hz)
671
917
2285
2510
7141
7776
14013
–3 dB
Frequency
(Hz)
671
917
2285
2510
7141
7776
14013
–10–
20.8
20.6
19.9
19.3
18.9
18.7
18.0
17.9
17.8
17.0
16.3
16.1
16.0
15.0
2.5 V
2.5 V
2.7
3.0
5.1
7.5
10.2
11.4
15.5
2.5 V, +2.5 V
+2.5 V
19.8
19.6
18.9
18.3
17.9
17.7
16.7
+2.5 V
16.9
16.8
16.0
15.3
15.1
15.0
14.0
20.6
20.4
19.6
19.0
18.7
18.5
17.8
17.8
17.4
16.8
16.2
15.9
15.7
14.8
1.25 V
1.25 V
Input Range
Input Range
Input Range
1.5
1.8
3.0
4.5
5.9
6.5
10.3
1.25 V, +1.25 V, 625 mV, +625 mV
+1.25 V
19.6
19.4
18.6
18.0
17.7
17.5
17.1
+1.25 V
16.8
16.4
15.8
15.2
14.9
14.7
13.8
19.6
19.4
18.6
18.0
17.7
17.5
17.1
16.8
16.4
15.8
15.2
14.9
14.7
13.8
625 mV
625 mV
+625 mV
18.6
18.4
17.6
17.0
16.7
16.5
16.1
+625 mV
15.8
15.4
14.8
14.2
13.9
13.7
12.8
REV. 0