Datasheet

MAX1421
12-Bit, 40Msps, 3.3V, Low-Power ADC
with Internal Reference
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ELECTRICAL CHARACTERISTICS (continued)
(V
AVDD
= V
DVDD
= 3.3V, AGND = DGND = 0, V
IN
= ±1.024V, differential input voltage at -0.5dB FS, internal reference,
f
CLK
= 40MHz (50% duty cycle), digital output load C
L
≈ 10pF, T
A
≥ +25°C guaranteed by production test, T
A
< +25°C guarnateed
by design and characterization. Typical values are at T
A
= +25°C.)
PARAMETER
SYMBOL
CONDITIONS
MIN TYP MAX
UNITS
Differential Gain DG ±1%
Differential Phase DP
±0.25
degrees
ANALOG INPUTS (INP, INN, CML)
Input Resistance R
IN
Either input to ground
32.5
kΩ
Input Capacitance C
IN
Either input to ground 4 pF
Common-Mode Input Level
(Note 5)
V
CML
V
AVDD
× 0.5
V
Common-Mode Input Voltage
Range (Note 5)
V
CMVR
V
CML
±5%
V
Differential Input Range V
IN
V
INP
- V
INN
(Note 6)
±V
DIFF
V
Small-Signal Bandwidth
BW
-3dB
(Note 7) 400
MHz
Large-Signal Bandwidth
FPBW
-3dB
(Note 7) 150
MHz
Overvoltage Recovery OVR 1.5
✕
FS input 1
Clock
Cycle
INTERNAL REFERENCE (REFIN bypassed with 0.22µF in parallel with 1nF)
Common-Mode Reference Input
Voltage
V
CML
At CML
V
AVDD
✕
0.5
V
Positive Reference Voltage
Range
V
REFP
At REFP
V
CML
+ 0.512
V
Negative Reference Voltage
Range
V
REFN
At REFN
V
CML
- 0.512
V
Differential Reference Voltage
Range
V
DIFF
(Note 6)
1.024
±5%
V
Differential Reference
Temperature Coefficient
REFTC ±100
ppm/°C
EXTER N AL R EF ER EN C E (V
REFIN
= 2.048V)
REFIN Input Resistance R
IN
(Note 8) 5 kΩ
REFIN Input Capacitance C
IN
10 pF
REFIN Reference Input Voltage
V
REFIN
2.048
±10%
V
Differential Reference Voltage V
DIFF
(Note 6)
0.92
✕
V
REFIN /
2
V
REFIN /
2
1.08
✕
V
REFIN /
2
V
EXTERNAL REFERENCE (V
REFIN
= AGND, reference voltage applied to REFP, REFN, and CML)
REFP, REFN, CML Input Current
I
IN
-200 +200
µA
REFP, REFN, CML Input
Capacitance
C
IN
15 pF