Datasheet
3
21576512f
LTC2157-12/
LTC2156-12/LTC2155-12
CONVERTER CHARACTERISTICS
The l denotes the specifications which apply over the full operating
temperature range, otherwise specifications are at T
A
= 25°C. (Note 5)
PARAMETER CONDITIONS
LTC2157-12 LTC2156-12 LTC2155-12
UNITSMIN TYP MAX MIN TYP MAX MIN TYP MAX
Resolution (No Missing Codes)
l
12 12 12 Bits
Integral Linearity Error Differential Analog Input (Note 6)
l
–2.3 ±0.26 2.3 –2.2 ±0.30 2.2 –1.9 ±0.30 1.9 LSB
Differential Linearity Error Differential Analog Input
l
–0.6 ±0.16 0.8 –0.6 ±0.16 0.6 –0.6 ±0.16 0.6 LSB
Offset Error (Note 7)
l
–13 ±5 13 –13 ±5 13 –13 ±5 13 mV
Gain Error External Reference
l
–4 ±1 2.2 –4 ±1 2.2 –4 ±1 2.2 %FS
Offset Drift ±20 ±20 ±20 µV/°C
Full-Scale Drift Internal Reference
External Reference
±30
±10
±30
±10
±30
±10
ppm/°C
ppm/°C
Transition Noise 0.54 0.54 0.54 LSB
RMS
ANALOG INPUT
The l denotes the specifications which apply over the full operating temperature range, otherwise
specifications are at T
A
= 25°C. (Note 5)
SYMBOL PARAMETER CONDITIONS MIN TYP MAX UNITS
V
IN
Analog Input Range (A
IN
+
– A
IN
–
) 1.7V < V
DD
< 1.9V
l
1.5 V
P-P
V
IN(CM)
Analog Input Common Mode (A
IN
+
+ A
IN
–
)/2 Differential Analog Input (Note 8)
l
V
CM
– 20mV V
CM
V
CM
+ 20mV V
V
SENSE
External Voltage Reference Applied to SENSE External Reference Mode
l
1.200 1.250 1.300 V
I
IN1
Analog Input Leakage Current 0 < A
IN
+
, A
IN
–
< V
DD
, No Encode
l
–1 1 µA
I
IN2
PAR/SER Input Leakage Current 0 < PAR/SER < V
DD
l
–1 1 µA
I
IN3
SENSE Input Leakage Current 1.2V < SENSE < 1.3V
l
–1 1 µA
t
AP
Sample-and-Hold Acquisition Delay Time 1 ns
t
JITTER
Sample-and-Hold Acquisition Delay Jitter 0.15 ps
RMS
CMRR Analog Input Common Mode Rejection Ratio 75 dB
BW-3B Full-Power Bandwidth 1250 MHz
DYNAMIC ACCURACY
The l denotes the specifications which apply over the full operating temperature range,
otherwise specifications are at T
A
= 25°C. A
IN
= –1dBFS. (Note 5)
SYMBOL PARAMETER CONDITIONS
LTC2157-12 LTC2156-12 LTC2155-12
UNITSMIN TYP MAX MIN TYP MAX MIN TYP MAX
SNR Signal-to-Noise Ratio 15MHz Input
70MHz Input
140MHz Input
l
66.9
68.5
68.4
68.0
67.3
68.5
68.3
67.9
67.4
68.5
68.3
67.8
dBFS
dBFS
dBFS
SFDR Spurious Free Dynamic Range
2nd or 3rd Harmonic
15MHz Input
70MHz Input
140MHz Input
l
71
90.6
88
80
74
90.1
89
81
75
90
88
80
dBFS
dBFS
dBFS
Spurious Free Dynamic Range
4th Harmonic or Higher
15MHz Input
70MHz Input
140MHz Input
l
81
98
95
85
82
98
95
87
83
98
95
88
dBFS
dBFS
dBFS
S/(N+D) Signal-to-Noise Plus
Distortion Ratio
15MHz Input
70MHz Input
140MHz Input
l
66.1
68.4
68.3
67.7
66.7
68.4
68.3
67.7
66.8
68.4
68.3
67.7
dBFS
dBFS
dBFS
Crosstalk Crosstalk Between Channels Up to 315MHz Input –95 –95 –95 dB