max5883egmtd Maxim Integrated Products, Inc., max5883egmtd Datasheet - Page 14

• Manufacturer Part Number: max5883egmtd
• Description: Max5883 3.3v, 12-bit, 200msps High Dynamic Performance Dac With Cmos Inputs
• Manufacturer: Maxim Integrated Products, Inc.

Integral nonlinearity is the deviation of the values on an
actual transfer function from either a best straight line fit
(closest approximation to the actual transfer curve) or a
line drawn between the end points of the transfer func-
tion, once offset and gain errors have been nullified. For
a DAC, the deviations are measured at every individual
step.
Differential nonlinearity is the difference between an
actual step height and the ideal value of 1 LSB. A DNL
error specification of less than 1 LSB guarantees no
missing codes and a monotonic transfer function.
The offset error is the difference between the ideal and
the actual offset current. For a DAC, the offset point is
the average value at the output for the two midscale
digital input codes with respect to the full scale of the
DAC. This error affects all codes by the same amount.
A gain error is the difference between the ideal and the
actual full-scale output voltage on the transfer curve,
after nullifying the offset error. This error alters the slope
of the transfer function and corresponds to the same
percentage error in each step.
The settling time is the amount of time required from the
start of a transition until the DAC output settles its new
output value to within the converter’s specified accuracy.
A glitch is generated when a DAC switches between
two codes. The largest glitch is usually generated
around the midscale transition, when the input pattern
transitions from 011...111 to 100...000. The glitch ener-
gy is found by integrating the voltage of the glitch at the
midscale transition over time. The glitch energy is usu-
ally specified in pV-s.
3.3V, 12-Bit, 200Msps High Dynamic
Performance DAC with CMOS Inputs
14
Static Performance Parameter Definitions
______________________________________________________________________________________
Differential Nonlinearity (DNL)
Integral Nonlinearity (INL)
Glitch Energy
Settling Time
Offset Error
Gain Error
For a waveform perfectly reconstructed from digital sam-
ples, the theoretical maximum SNR is the ratio of the full-
scale analog output (RMS value) to the RMS quantization
error (residual error). The ideal, theoretical maximum SNR
can be derived from the DAC’s resolution (N bits):
However, noise sources such as thermal noise, refer-
ence noise, clock jitter, etc., affect the ideal reading;
therefore, SNR is computed by taking the ratio of the
RMS signal to the RMS noise, which includes all spec-
tral components minus the fundamental, the first four
harmonics, and the DC offset.
SFDR is the ratio of RMS amplitude of the carrier fre-
quency (maximum signal components) to the RMS
value of their next-largest distortion component. SFDR
is usually measured in dBc and with respect to the car-
rier frequency amplitude or in dB FS with respect to the
DAC’s full-scale range. Depending on its test condition,
SFDR is observed within a predefined window or
to Nyquist.
The two-tone IMD is the ratio expressed in dBc (or dB FS)
of either input tone to the worst 3rd-order (or higher) IMD
products. Note that 2nd-order IMD products usually fall at
frequencies that can be easily removed by digital filtering;
therefore, they are not as critical as 3rd-order IMDs. The
two-tone IMD performance of the MAX5883 was tested
with the two individual input tone levels set to at least
-6dB FS and the four-tone performance was tested at an
output frequency of 32MHz and amplitude of -12dB FS.
SNR
Dynamic Performance Parameter
Two-/Four-Tone Intermodulation
Spurious-Free Dynamic Range (SFDR)
dB
= 6.02
Signal-to-Noise Ratio (SNR)
dB
N + 1.76
Distortion (IMD)
dB
Definitions