
Converter AC Characteristics (Notes 6, 7, 8, 9) (Continued) The following specifications apply to the LM12454, LM12458, and LM12H458 for V
A+=VD+ = 5V, VREF+ = 5V, VREF = 0V,
12-bit + sign conversion mode, f
CLK = 8.0 MHz (LM12H458) or fCLK = 5.0 MHz (LM12454/8), RS =25
, source impedance for
V
REF+ and VREF
≤ 25, fully-differential input with fixed 2.5V common-mode voltage, and minimum acquisition time unless
otherwise specified. Boldface limits apply for T
A =TJ =TMIN to TMAX; all other limits TA =TJ = 25C.
Symbol
Parameter
Conditions
Typical
Units
t
WD
“Watchdog” Mode
Comparison Time
Sequencer States S6, S4, and S5
11 (t
CLK)
11 (t
CLK)+50ns
(max)
DSNR
Differential Signal-to-Noise
Ratio
V
IN = ±5V
f
IN = 1 kHz
77.5
dB
f
IN = 20 kHz
75.2
dB
f
IN = 40 kHz
74.7
dB
SESNR
Single-Ended Signal-to-Noise
Ratio
V
IN =5Vp-p
f
IN = 1 kHz
69.8
dB
f
IN = 20 kHz
69.2
dB
f
IN = 40 kHz
66.6
dB
DSINAD
Differential Signal-to-Noise +
Distortion Ratio
V
IN = ±5V
f
IN = 1 kHz
76.9
dB
f
IN = 20 kHz
73.9
dB
f
IN = 40 kHz
70.7
dB
SESINAD
Single-Ended Signal-to-Noise
+ Distortion Ratio
V
IN =5Vp-p
f
IN = 1 kHz
69.4
dB
f
IN = 20 kHz
68.3
dB
f
IN = 40 kHz
65.7
dB
DTHD
Differential Total Harmonic
Distortion
V
IN = ±5V
f
IN = 1 kHz
85.8
dB
f
IN = 20 kHz
79.9
dB
f
IN = 40 kHz
72.9
dB
SETHD
Single-Ended Total Harmonic
Distortion
V
IN =5Vp-p
f
IN = 1 kHz
80.3
dB
f
IN = 20 kHz
75.6
dB
f
IN = 40 kHz
72.8
dB
DENOB
Differential Effective Number
of Bits
V
IN = ±5V
f
IN = 1 kHz
12.6
Bits
f
IN = 20 kHz
12.2
Bits
f
IN = 40 kHz
12.1
Bits
SEENOB
Single-Ended Effective
Number of Bits
V
IN =5Vp-p
f
IN = 1 kHz
11.3
Bits
f
IN = 20 kHz
11.2
Bits
f
IN = 40 kHz
10.8
Bits
DSFDR
Differential Spurious Free
Dynamic Range
V
IN = ±5V
f
IN = 1 kHz
87.2
dB
f
IN = 20 kHz
78.9
dB
f
IN = 40 kHz
72.8
dB
Multiplexer
Channel-to-Channel
Crosstalk
V
IN =5VP-P,fIN = 40 kHz,
LM12454 MUXOUT Only
76
dB
V
IN =5VP-P,fIN = 40 kHz,
LM12(H)458 MUX plus Converter
78
dB
t
PU
Power-Up Time
10
ms
t
WU
Wake-Up Time
10
ms
LM12454/LM12458/LM12H458
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