Datasheet
5
LTC1608
Note 10: Signal-to-Noise Ratio (SNR) is measured at 5kHz and distortion
is measured at 100kHz. These results are used to calculate Signal-to-Nosie
Plus Distortion (SINAD).
Note 11: Guaranteed by design, not subject to test.
Note 12: Recommended operating conditions.
Note 13: The falling CONVST edge starts a conversion. If CONVST returns
high at a critical point during the conversion it can create small errors. For
best performance ensure that CONVST returns high either within 250ns
after conversion start or after BUSY rises.
Note 14: The acquisition time would go up to 400ns and the conversion
time would go up to 1.8µs. However, the throughput time (acquisition +
conversion) is guaranteed by test to be 2µs max.
Note 15: If RD↓ precedes CS↓, the output enable will be gated by CS↓.
Note 4: When these pin voltages are taken below V
SS
, they will be clamped
by internal diodes. This product can handle input currents greater than
100mA below V
SS
without latchup. These pins are not clamped to V
DD
.
Note 5: V
DD
= 5V, V
SS
= –5V, f
SMPL
= 500kHz, and t
r
= t
f
= 5ns unless
otherwise specified.
Note 6: Linearity, offset and full-scale specification apply for a single-
ended A
IN
+
input with A
IN
–
grounded.
Note 7: Integral nonlinearity is defined as the deviation of a code from a
straight line passing through the actual endpoints of the transfer curve.
The deviation is measured from the center of the quantization band.
Note 8: Typical RMS noise at the code transitions.
Note 9: Bipolar offset is the offset voltage measured from –0.5LSB when
the output code flickers between 0000 0000 0000 0000 and 1111 1111
1111 1111.
ELECTRICAL CHARACTERISTICS
TYPICAL PERFOR A CE CHARACTERISTICS
UW
Integral Nonlinearity
vs Output Code
CODE
–32768 32767
INL (LSB)
0
0.5
–16384 16384
0
1608 G01
1.0
1.5
2.0
–0.5
–1.0
–1.5
–2.0
Differential Nonlinearity
vs Output Code
CODE
–32768 32767
–1.0
DNL (LSB)
–0.8
–0.4
–0.2
0
1.0
0.4
–16384 16384
0
1608 G02
–0.6
0.6
0.8
0.2
S/(N + D) vs Input Frequency
and Amplitude
FREQUENCY (Hz)
100
90
80
70
60
50
40
30
20
10
0
SINAD (dB)
1608 G03
1k
10k
100k 1M
V
IN
= 0dB
V
IN
= –20dB
V
IN
= –40dB
Signal-to-Noise Ratio
vs Input Frequency Distortion vs Input Frequency
Spurious-Free Dynamic Range
vs Input Frequency
FREQUENCY (Hz)
100
90
80
70
60
50
40
30
20
10
0
SIGNAL-TO-NOISE RATIO (dB)
1608 G04
1k
10k
100k 1M
INPUT FREQUENCY (Hz)
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
AMPLITUDE (dB BELOW THE FUNDAMENTAL)
1608 G05
1k
10k
100k 1M
THD
3RD
2ND
INPUT FREQUENCY (Hz)
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
–110
SPURIOUS-FREE DYNAMIC RANGE (dB)
1608 G06
1k
10k
100k 1M