MAX1080 Datasheet, PDF (21/24 Pages) Maxim Integrated Products – 300ksps/400ksps, Single-Supply, Low-Power, 8-Channel, Serial 10-Bit ADCs with Internal Reference

300ksps/400ksps, Single-Supply, Low-Power,
8-Channel, Serial 10-Bit ADCs with Internal Reference
ANALOG
INPUTS
V_DD1
1 _CH0
V_{DD1 20}
2 _CH1
V_DD2 19
3 CH2
SCLK ₁₈
4 CH3 _MAX1080 CS 17
5
MAX1081
CH4
DIN ₁₆
6 CH5
SSTRB ₁₅
7 CH6
DOUT ₁₄
8 CH7
GND 13
9 COM
REFADJ 12
10 SHDN
REF 11
0.1µF
+5V +5V
OR OR
+3V +3V
10µF
(POWER SUPPLIES)
SCK
PCS0
MOSI
MC683XX
MISO
4.7µF
0.01µF
(GND)
Figure 17. QSPI Connections
XF
CLKX
TMS320LC3x
CLKR
DX
DR
FSR
CS
SCLK
MAX1080
MAX1081
DIN
DOUT
SSTRB
Figure 18. MAX1080/MAX1081-to-TMS320 Serial Interface
Aperture Width
Aperture width (t_AW) is the time the T/H circuit requires
to disconnect the hold capacitor from the input circuit
(for instance, to turn off the sampling bridge and put
the T/H unit in hold mode).
Aperture Jitter
Aperture jitter (t_AJ) is the sample-to-sample variation in
the time between the samples.
Aperture Delay
Aperture delay (t_AD) is the time defined between the
rising edge of the sampling clock and the instant when
an actual sample is taken.
Signal-to-Noise Ratio (SNR)
For a waveform perfectly reconstructed from digital
samples, the SNR is the ratio of the full-scale analog
input (RMS value) to the RMS quantization error (resid-
ual error). The ideal, theoretical minimum analog-to-dig-
ital noise is caused only by quantization error and
results directly from the ADC’s resolution (N bits):
SNR = (6.02 ✕ N + 1.76)dB
In reality, there are other noise sources besides quanti-
zation noise, including thermal noise, reference noise,
clock jitter, etc. Therefore, SNR is calculated by taking
the ratio of the RMS signal to the RMS noise, which
includes all spectral components minus the fundamen-
tal, the first five harmonics, and the DC offset.
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