6
LTC1415
TYPICAL PERFORMANCE CHARACTERISTICS
U
W
Input Common Mode Rejection
vs Input Frequency
Power Supply Feedthrough vs
Ripple Frequency
RIPPLE FREQUENCY (Hz)
AMPLITUDE
OF
POWER
SUPPLY
FEEDTHROUGH
(dB)
0
–10
–20
–30
–40
–50
–60
–70
–80
–90
–100
1k
100k
1M
2M
LTC1415 TPC08
10k
VDD
OVDD
DGND
INPUT FREQUENCY (Hz)
COMMON
MODE
REJECTION
(dB)
80
70
60
50
40
30
20
10
0
1k
100k
1M 2M
LTC1415 TPC09
10k
PI FU CTIO S
UU
U
RD (Pin 22): Read Input. This enables the output
drivers when CS is low.
CONVST (Pin 23): Conversion Start Signal. This active
low signal starts a conversion on its falling edge.
CS (Pin 24): The Chip Select input must be low for the
ADC to recognize CONVST and RD inputs.
BUSY (Pin 25): The BUSY output shows the converter
status. It is low when a conversion is in progress. Its
rising edge may be used to latch the output data.
0VDD (Pin 26): Digital output buffer supply. Short to Pin
28 for 5V output. Tie to 3V for driving 3V logic.
DVDD (Pin 27): 5V Positive Supply. Short to Pin 28.
AVDD (Pin 28): 5V Positive Supply. Bypass to AGND
with 10
F tantalum in parallel with 0.1F or 10F
ceramic.
+AIN (Pin 1): Positive Analog Input, 0V to 4.096V.
–AIN (Pin 2): Negative Analog Input, 0V to 4.096V.
VREF (Pin 3): 2.50V Reference Output.
REFCOMP (Pin 4): Bypass to AGND with 10
F tantalum
in parallel with 0.1
F or 10F ceramic.
AGND (Pin 5): Analog Ground.
D11 to D4 (Pins 6 to 13): Three-State Data Outputs.
DGND (Pin 14): Digital Ground.
D3 to D0 (Pins 15 to 18): Three-State Data Outputs.
OGND (Pin 19): Digital Output Buffer Ground.
NAP/SLP (Pin 20): Power Shutdown Mode. High for
quick wake-up Nap mode.
SHDN (Pin 21): Power Shutdown Input. A low logic
level will invoke the Shutdown mode selected by the
NAP/SLP pin. Tie high if unused.