MAX1276EVKIT Maxim Integrated, MAX1276EVKIT Datasheet - Page 16

• Manufacturer Part Number: MAX1276EVKIT
• Description: Data Conversion IC Development Tools Evaluation Kit/Evaluation System for the MAX1070/71/72/75#79/MAX1224/25/MAX1274#79
• Manufacturer: Maxim Integrated
• Series: MAX1276, MAX1278r

Specifications of MAX1276EVKIT

• Interface Type: QSPI, Serial (SPI, Microwire)

Problem: Measurements show high levels
of distortion.
• Verify AIN levels are within the specified ranges for
• When using on-board buffers, verify that ACIN inputs
• Verify the input signal generators have the expected
• Use a spectrum analyzer to verify signal integrity
• Verify the input signal generators have the expected
• If experimenting with R1 and R2 or C1 values (or
• Verify SPI inputs are correct and meet all timing and
Problem: FFT measurements show excessive
signal spreading.
• If using coherent sampling techniques (preferred),
• If using noncoherent sampling techniques, be sure
• In all cases, be certain that your FFT routines are
• Verify that master-clock-derived SPI input signals
MAX1276 Evaluation Kit/Evaluation System
16
the part, both with respect to supply and reference
values. Failure to do so results in clipping of the dif-
ferential input. This is usually observed as excessive
harmonic content.
and AIN outputs are within the linear range of the
amplifiers. Inspect waveforms for signs of clipping.
level of purity. Many signal generators require exter-
nal filters to provide true 12-bit purity. Also ensure
the signal generators are operating in their linear
range. It may be necessary to adjust the resistive
feedback paths around the internal buffers if more
signal gain is required.
both at the source and at the inputs of the ADC
under test.
termination; the EV kit is set up with 50Ω termination.
dual input capacitors), verify that the buffers or
external sources are maintaining stability. Also verify
that the source impedance is not interacting with the
test device. (Refer to the product datasheet for typi-
cal THD performance vs. source impedance.)
level requirements. Verify periodic sampling is as
expected when performing dynamic measurements.
check the following. Ensure signal and master clock
generators have the required frequency resolution to
maintain full coherency. Synchronize all coherent
sources using proper connection techniques; be
certain proper locking is achieved.
to apply proper windowing functions to the data.
operating correctly and are being supplied with
enough samples to show the desired level of resolu-
tion and accuracy.
are in fact coherent and periodic.
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A deserializer board can be used to convert the serial-
output format of the MAX1276 family to a parallel data
format. Use of a deserializer greatly simplifies testing
when using a logic analyzer. The circuit shown in
8 has been used successfully with the EV kit. It consists
of a shift register (CD74AC164E) followed by a transpar-
ent latch (MC74AC373N). The deserializer board should
be powered from the VLOGIC and DGND pads.
The deserializer requires an additional set of signals to
drive its circuitry and the logic analyzer. An example
set of SPI and deserializer waveforms is detailed in
Figure
to 16-bit digital word lengths. The MAX1276 family pro-
vides 12-bit digital outputs. The serial digital output of
the test device, D[11:0], can be read in parallel format
as B[11:0]. Be sure to configure the logic analyzer
accordingly.
9. The deserializer board shown can support up
Deserializer Board (Optional)
Deserializer Signals
Figure