
6
LTC1420
1420fa
TYPICAL PERFOR A CE CHARACTERISTICS
UW
IDD vs Clock Frequency
CLOCK FREQUENCY (MHz)
0
40
I DD
(mA)
42
44
46
48
50
52
246
8
1420 G10
10
VREF = 4.096V
VREF = 2.048V
CLOCK FREQUENCY (MHz)
0
1.0
1.2
1.4
8
6
1420 G11
0.8
0.6
24
10
0.4
0.2
0
I SS
(mA)
ISS vs Clock Frequency
CMRR vs Input Frequency
INPUT FREQUENCY (MHz)
0.01
0
CMRR
(dB)
10
30
40
50
1
90
1420 G12
20
0.1
10
60
70
80
+AIN (Pin 1): Positive Analog Input.
–AIN (Pin 2): Negative Analog Input.
VCM (Pin 3): 2.5V Reference Output.Optional input com-
mon mode for single supply operation. Bypass to GND
with a 1F to 10F ceramic.
SENSE (Pin 4): Reference Programming Pin. Ground
selects VREF = 4.096V. Short to VREF for 2.048V. Connect
SENSE to VDD to drive VREF with an external reference.
VREF (Pin 5): DAC Reference. Bypass to GND with a 1F to
10F ceramic.
GND (Pin 6): DAC Reference Ground.
VDD (Pin 7): Analog 5V Supply. Bypass to GND with a 1F
to 10F ceramic.
GND (Pin 8): Analog Power Ground.
D11 to D0 (Pins 9 to 20): Data Outputs. The output format
is two’s complement.
OGND (Pin 21): Output Logic Ground. Tie to GND.
OVDD (Pin 22): Positive Supply for the Output Logic.
Connect to Pin 23 for 5V logic. If not shorted to Pin 23,
bypass to GND with a 1F ceramic.
PIN FUNCTIONS
UU
U
LTC1420 Nonaveraged 4096 Point FFT
FREQUENCY (MHz)
0
–120
AMPLITUDE
(dB)
–100
–80
–60
–40
–20
0
123
4
1420 G13
5
fSAMPLE = 10Msps
fIN = 5.048828125MHz
SFDR = 83.2dB
SINAD = 71dB
VIN = 4VP-P
±5V SUPPLIES