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Typical operating characteristics, Electrical characteristics (continued) – Rainbow Electronics MAX1421 User Manual

Page 5

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MAX1421

12-Bit, 40Msps, +3.3V, Low-Power ADC

with Internal Reference

_______________________________________________________________________________________

5

Note 1: Internal reference, REFIN bypassed to AGND with a combination of 0.22µF in parallel with 1nF capacitor.
Note 2: External +2.048V reference applied to REFIN.
Note 3: Internal reference disabled. V

REFIN

= 0, V

REFP

= +2.162V, V

CML

= +1.65V, and V

REFN

= +1.138V.

Note 4: IMD is measured with respect to either of the fundamental tones.
Note 5: Specifies the common-mode range of the differential input signal supplied to the MAX1421.
Note 6: V

DIFF

= V

REFP

- V

REFN

Note 7: Input bandwidth is measured at a 3dB level.
Note 8: V

REFIN

is internally biased to +2.048V through a 10k

Ω resistor.

Note 9: Measured as the ratio of the change in mid-scale offset voltage for a ± 5% change in V

AVDD

using the internal reference.

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

= T

MIN

to T

MAX

, unless otherwise noted. Typical values are at

T

A

= +25°C.)

PARAMETER

SYMBOL

CONDITIONS

MIN

TYP

MAX

UNITS

Pipeline Delay (Latency)

Figure 5

7

f

CLK

cycles

Aperture Delay

t

AD

Figure 9

2

ns

Aperture Jitter

t

AJ

Figure 9

2

ps

Data Output Delay

t

OD

Figure 5

5

10

14

ns

Bus Enable Time

t

BE

Figure 4

5

ns

Bus Disable Time

t

BD

Figure 4

5

ns

Typical Operating Characteristics

(V

AVDD

= V

DVDD

= +3.3V, AGND = DGND = 0, V

IN

= ±1.024V, differential input voltage, f

CLK

= 40MHz (50% duty cycle), digital output

load C

L

= 10pF, T

A

= T

MIN

to T

MAX,

unless otherwise noted. Typical values are at T

A

= +25°C.)

-120

-80

-100

-40

-60

-20

0

0

10

5

15

20

FFT PLOT, 4096-POINT RECORD,

DIFFERENTIAL INPUT

MAX1421 toc01

ANALOG INPUT FREQUENCY (MHz)

AMPLITUDE (dB)

f

IN

= 7.5439934MHz

A

IN

= -0.45dB FS

HD3

HD2

-120

-80

-100

-40

-60

-20

0

0

10

5

15

20

FFT PLOT, 4096-POINT RECORD,

DIFFERENTIAL INPUT

MAX1421 toc02

ANALOG INPUT FREQUENCY (MHz)

AMPLITUDE (dB)

f

IN

= 19.9047628MHz

A

IN

= -0.50dB FS

HD2

HD3

-120

-80

-100

-40

-60

-20

0

0

10

5

15

20

FFT PLOT, 4096-POINT RECORD,

DIFFERENTIAL INPUT

MAX1421 toc03

ANALOG INPUT FREQUENCY (MHz)

AMPLITUDE (dB)

f

IN

= 38.5440183MHz

A

IN

= -0.49dB FS

HD3

HD2