MAX1196ECM+D Maxim Integrated Products, MAX1196ECM+D Datasheet - Page 18

• Manufacturer Part Number: MAX1196ECM+D
• Description: IC ADC 8BIT 40MSPS DL 48-TQFP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1196ECM+D

• Number Of Bits: 8
• Sampling Rate (per Second): 40M
• Data Interface: Parallel
• Number Of Converters: 2
• Power Dissipation (max): 108mW
• Voltage Supply Source: Single Supply
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: 48-TQFP Exposed Pad, 48-eTQFP, 48-HTQFP, 48-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Dual 8-Bit, 40Msps, 3V, Low-Power ADC with
Internal Reference and Multiplexed Parallel Outputs
Figure 8. External Buffered (MAX4250) Reference Drive Using a MAX6062 Bandgap Reference
produced in the voltage-reference and buffer stages.
This filtered noise density, which decreases for higher
frequencies, meets the noise levels specified for preci-
sion-ADC operation.
Connecting each REFIN to analog ground disables the
internal reference of each device, allowing the internal
reference ladders to be driven directly by a set of exter-
nal reference sources. Followed by a 10Hz lowpass fil-
ter and precision voltage-divider, the MAX6066
generates a DC level of 2.500V. The buffered outputs of
this divider are set to 2.0V, 1.5V, and 1.0V, with an
accuracy that depends on the tolerance of the divider
resistors.
Those three voltages are buffered by the MAX4252,
which provides low noise and low DC offset. The individ-
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NOTE: ONE FRONT-END REFERENCE CIRCUIT DESIGN CAN BE USED WITH UP TO 1000 ADCs.
3.3V
Unbuffered External Reference Drives
MAX6062
1
3
2
10Hz LOWPASS
FILTER
0.1µF
16.2kΩ
1µF
0.1µF
3
4
Multiple ADCs
MAX4250
5
2
3.3V
1
10Hz LOWPASS
FILTER
162Ω
100µF
ual voltage followers are connected to 10Hz lowpass fil-
ters, which filter both the reference-voltage and amplifier
noise to a level of 3nV/√Hz. The 2.0V and 1.0V reference
voltages set the differential full-scale range of the asso-
ciated ADCs at 2V
the ADCs’ internal ladder resistances between them.
Note that the common power supply for all active com-
ponents removes any concern regarding power-supply
sequencing when powering up or down.
With the outputs of the MAX4252 matching better than
0.1%, the buffers and subsequent lowpass filters can
be replicated to support as many as 32 ADCs. For
applications requiring more than 32 matched ADCs, a
voltage-reference and divider string common to all con-
verters is highly recommended.
0.1µF
0.1µF
2.048V
0.1µF
0.1µF
N.C.
N.C.
0.1µF
0.1µF
P-P
0.1µF
0.1µF
. The 2.0V and 1.0V buffers drive
29
31
32
29
31
32
1
2
1
2
REFOUT
REFIN
REFP
REFN
COM
REFOUT
REFIN
REFP
REFN
COM
MAX1196
MAX1196
N = 1000
N = 1
0.1µF
2.2µF
10V