kad5610p Kenet Inc., kad5610p Datasheet - Page 26

• Manufacturer Part Number: kad5610p
• Description: Dual 10-bit, 250/210/170/125msps A/d Converter
• Manufacturer: Kenet Inc.

Exposed Paddle
The exposed paddle must be electrically connected
to analog ground (AVSS) and should be connected
to a large copper plane using numerous vias for opti-
mal thermal performance.
Bypass and Filtering
Bulk capacitors should have low equivalent series re-
sistance. Tantalum is a good choice. For best per-
formance, keep ceramic bypass capacitors very
close to device pins. Longer traces will increase in-
ductance, resulting in diminished dynamic perform-
ance and accuracy. Make sure that connections to
ground are direct and low impedance. Avoid form-
ing ground loops.
LVDS Outputs
Output traces and connections must be designed for
50Ω (100Ω differential) characteristic impedance.
Keep traces direct and minimize bends where possi-
ble. Avoid crossing ground and power plane breaks
with signal traces.
LVCMOS Outputs
Output traces and connections must be designed for
50Ω characteristic impedance.
Unused Inputs
Standard logic inputs (RESETN, CSB, SCLK, SDIO, SDO)
which will not be operated do not require connec-
tion to ensure optimal ADC performance. These in-
puts can be left floating if they are not used. Tri-level
inputs (NAPSLP, OUTMODE, OUTFMT, CLKDIV) accept
a floating input as a valid state, and therefore should
be biased according to the desired functionality.
Definitions
Analog Input Bandwidth is the analog input fre-
quency at which the spectral output power at the
fundamental frequency (as determined by FFT analy-
sis) is reduced by 3dB from its full-scale low-frequency
value. This is also referred to as Full Power Bandwidth.
Aperture Delay or Sampling Delay is the time re-
quired after the rise of the clock input for the sam-
pling switch to open, at which time the signal is held
for conversion.
Aperture Jitter is the RMS variation in aperture delay
for a set of samples.
Rev 0.5.1 Preliminary
KAD5610P
Clock Duty Cycle is the ratio of the time the clock
wave is at logic high to the total time of one clock
period.
Differential Non-Linearity (DNL) is the deviation of any
code width from an ideal 1 LSB step.
Effective Number of Bits (ENOB) is an alternate
method of specifying Signal to Noise-and-Distortion
Ratio (SINAD). In dB, it is calculated as: ENOB =
(SINAD-1.76) / 6.02
Gain Error is the ratio of the difference between the
voltages that cause the lowest and highest code
transitions to the full-scale voltage (less 2 LSB). It is
typically expressed in percent.
Integral Non-Linearity (INL) is the deviation of each
individual code from a line drawn from negative full-
scale (1/2 LSB below the first code transition) through
positive full-scale (1/2 LSB above the last code transi-
tion). The deviation of any given code from this line is
measured from the center of that code.
Least Significant Bit (LSB) is the bit that has the small-
est value or weight in a digital word. Its value in terms
of input voltage is V
in bits.
Missing Codes are output codes that are skipped
and will never appear at the ADC output. These
codes cannot be reached with any input value.
Most Significant Bit (MSB) is the bit that has the largest
value or weight.
Pipeline Delay is the number of clock cycles between
the initiation of a conversion and the appearance at
the output pins of the data.
Power Supply Rejection Ratio (PSRR) is the ratio of a
change in input voltage necessary to correct a
change in output code that results from a change in
power supply voltage.
Signal to Noise-and-Distortion (SINAD) is the ratio of
the RMS signal amplitude to the RMS value of the sum
of all other spectral components below one half the
clock frequency, including harmonics but excluding
DC.
Signal-to-Noise Ratio (without Harmonics) is the ratio
of the RMS signal amplitude to the sum of all other
spectral components below one-half the sampling
frequency, excluding harmonics and DC.
SNR and SINAD are either given in units of dBc (dB to
carrier) when the absolute power of the fundamental
is used as the reference, or dBFS (dB to full scale)
when the converter’s full-scale input power is used as
the reference.
FS
/(2
N
-1) where N is the resolution
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