Datasheet
LTC2314-14
8
231414fa
For more information www.linear.com/LTC2314-14
T
A
= 25°C, V
DD
= 5V, OV
DD
= 2.5V, f
SMPL
= 4.5Msps,
unless otherwise noted.
PIN FUNCTIONS
V
DD
(Pin 1): Power Supply. The ranges of V
DD
are 2.7V
to 3.6V and 4.75V to 5.25V. Bypass V
DD
to GND with a
2.2µF ceramic chip capacitor.
REF (Pin 2): Reference Input/Output. The REF pin volt
-
age defines the input span of the ADC, 0V to V
REF
. By
default, REF is an output pin and produces a reference
voltage V
REF
of either 2.048V or 4.096V depending on
V
DD
(see Table 2). Bypass to GND with a 2.2µF, low ESR,
high quality ceramic chip capacitor. The REF pin may be
overdriven with a voltage at least 50mV higher than the
internal reference voltage output.
GND (Pin 3): Ground. The GND pin must be tied directly
to a solid ground plane.
A
IN
(Pin 4): Analog Input. A
IN
is a single-ended input with
respect to GND with a range from 0V to V
REF
.
OV
DD
(Pin 5): I/O Interface Digital Power. The OV
DD
range
is 1.71V to 5.25V. This supply is nominally set to the
same supply as the host interface (1.8V, 2.5V, 3.3V or
5V). Bypass to GND with a 2.2µF ceramic chip capacitor.
SDO (Pin 6): Serial Data Output. The A/D conversion result
is
shifted out on SDO as a serial data stream with the MSB
first
through the LSB last. There is 1 cycle of conversion
latency. Logic levels are determined by OV
DD
.
SCK (Pin 7): Serial Data Clock Input. The SCK serial clock
falling edge advances the conversion process and outputs
a bit of the serialized conversion result, MSB first to LSB
last. SDO data transitions on the falling edge of SCK. A
continuous or burst clock may be used. Logic levels are
determined by OV
DD
.
CS (Pin 8): Chip Select Input. This active low signal starts
a conversion on the falling edge and frames the serial data
transfer. Bringing CS high places the sample-and-hold
into sample mode and also forces the SDO pin into high
impedance. Logic levels are determined by OV
DD
.
Output Supply Current (I
OVDD
)
vs Output Supply Voltage (OV
DD
)
OUTPUT SUPPLY VOLTAGE (V)
1.7
0
OUTPUT SUPPLY CURRENT (mA)
0.5
1.0
2.5
2.0
1.5
2.92.3 4.13.5 4.7 5.3
231414 G18
5Msps
f
SCK
= 87.5MHz
3Msps
f
SCK
= 52.5MHz
Supply Current (I
VDD
)
vs Supply Voltage (V
DD
)
SUPPLY VOLTAGE (V)
2.6
4.50
SUPPLY CURRENT (mA)
5.25
5.00
4.75
5.50
5.75
6.00
6.50
6.25
2.9 3.83.53.2 4.1 4.74.4 5.35.0
231414 G17
5Msps
f
SCK
= 87.5MHz
3Msps
f
SCK
= 52.5MHz
OPERATION
NOT ALLOWED
5Msps
3Msps
TYPICAL PERFORMANCE CHARACTERISTICS