MAX1195ECM+TD Maxim Integrated Products, MAX1195ECM+TD Datasheet - Page 19

• Manufacturer Part Number: MAX1195ECM+TD
• Description: IC ADC 8BIT 40MSPS DL 48-TQFP
• Manufacturer: Maxim Integrated Products

Specifications of MAX1195ECM+TD

• 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

Figure 11. T/H Aperture Timing
The MAX1195 requires high-speed board layout design
techniques. Locate all bypass capacitors as close to
the device as possible, preferably on the same side as
the ADC, using surface-mount devices for minimum
inductance. Bypass V
two parallel 0.1µF ceramic capacitors and a 2.2µF
bipolar capacitor to GND. Follow the same rules to
bypass the digital supply (OV
boards with separated ground and power planes pro-
duce the highest level of signal integrity. Consider the
use of a split ground plane arranged to match the
physical location of the analog ground (GND) and the
digital output driver ground (OGND) on the ADC’s
package. The two ground planes should be joined at a
Figure 10. Typical QAM Application Using the MAX1195
Dual, 8-Bit, 40Msps, 3V, Low-Power ADC with
DATA (T/H)
SAMPLED
ANALOG
INPUT
CLK
T/H
t
AD
TRACK
______________________________________________________________________________________
Internal Reference and Parallel Outputs
Grounding, Bypassing,
DD
, REFP, REFN, and COM with
and Board Layout
t
HOLD
AJ
DD
) to OGND. Multilayer
DOWNCONVERTER
TRACK
MAX2451
single point so the noisy digital ground currents do not
interfere with the analog ground plane. The ideal loca-
tion for this connection can be determined experimen-
tally at a point along the gap between the two ground
planes, which produces optimum results. Make this
connection with a low-value, surface-mount resistor (1Ω
to 5Ω), a ferrite bead, or a direct short.
Alternatively, all ground pins could share the same
ground plane, if the ground plane is sufficiently isolated
from any noisy, digital systems ground plane (e.g.,
downstream output buffer or DSP ground plane). Route
high-speed digital signal traces away from the sensitive
analog traces of either channel. Make sure to isolate
the analog input lines to each respective converter to
minimize channel-to-channel crosstalk. Keep all signal
lines short and free of 90° turns.
Integral nonlinearity (INL) is the deviation of the values
on an actual transfer function from a straight line. This
straight line can be either a best-straight-line fit or a line
drawn between the endpoints of the transfer function,
once offset and gain errors have been nullified. The
static linearity parameters for the MAX1195 are mea-
sured using the best-straight-line-fit method.
Differential nonlinearity (DNL) is the difference between
an actual step width and the ideal value of 1LSB. A
DNL error specification of less than 1LSB guarantees
no missing codes and a monotonic transfer function.
÷ 8
0°
Static Parameter Definitions
90°
Differential Nonlinearity
INA+
INA-
INB+
INB-
MAX1195
Integral Nonlinearity
PROCESSING
POST-
DSP
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