LTC2172CUKG-14PBF LINER [Linear Technology], LTC2172CUKG-14PBF Datasheet - Page 16
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LTC2172CUKG-14PBF
Manufacturer Part Number
LTC2172CUKG-14PBF
Description
14-Bit, 65Msps/40Msps/25Msps Low Power Quad ADCs
Manufacturer
LINER [Linear Technology]
Datasheet
1.LTC2172CUKG-14PBF.pdf
(32 pages)
LTC2172-14/
LTC2171-14/LTC2170-14
PIN FUNCTIONS
A
Input.
A
Input.
V
Equal to V
mode of the analog inputs of channels 1 and 2. Bypass
to ground with a 0.1μF ceramic capacitor.
A
Input.
A
Input.
REFH (Pins 6, 7): ADC High Reference. Bypass to Pin 8
and Pin 9 with a 2.2μF ceramic capacitor, and to ground
with a 0.1μF ceramic capacitor.
REFL (Pins 8, 9): ADC Low Reference. Bypass to Pin 6
and Pin 7 with a 2.2μF ceramic capacitor, and to ground
with a 0.1μF ceramic capacitor.
A
Input.
A
Input.
V
Equal to V
mode of the analog inputs of channels 3 and 4. Bypass
to ground with a 0.1μF ceramic capacitor.
A
Input.
A
Input.
V
Bypass to ground with 0.1μF ceramic capacitors. Adjacent
pins can share a bypass capacitor.
ENC
rising edge.
16
IN1
IN1
CM12
IN2
IN2
IN3
IN3
CM34
IN4
IN4
DD
+
–
+
–
+
–
+
–
+
(Pins 15, 16, 51, 52): 1.8V Analog Power Supply.
(Pin 17): Encode Input. Conversion starts on the
(Pin 11): Channel 3 Negative Differential Analog
(Pin 14): Channel 4 Negative Differential Analog
(Pin 2): Channel 1 Negative Differential Analog
(Pin 5): Channel 2 Negative Differential Analog
(Pin 10): Channel 3 Positive Differential Analog
(Pin 13): Channel 4 Positive Differential Analog
(Pin 1): Channel 1 Positive Differential Analog
(Pin 4): Channel 2 Positive Differential Analog
(Pin 12): Common Mode Bias Output, Nominally
(Pin 3): Common Mode Bias Output, Nominally
DD
DD
/2. V
/2. V
CM
CM
should be used to bias the common
should be used to bias the common
ENC
starts on the falling edge.
CS (Pin 19): In serial programming mode (PAR/SER = 0V),
CS is the serial interface chip select input. When CS is low,
SCK is enabled for shifting data on SDI into the mode
control registers. In parallel programming mode (PAR/SER
= V
can be driven with 1.8V to 3.3V logic.
SCK (Pin 20): In serial programming mode (PAR/SER
= 0V), SCK is the serial interface clock input. In parallel
programming mode (PAR/SER = V
or 1.75mA LVDS output currents. SCK can be driven with
1.8V to 3.3V logic.
SDI (Pin 21): In serial programming mode (PAR/SER =
0V), SDI is the serial interface data input. Data on SDI
is clocked into the mode control registers on the rising
edge of SCK. In parallel programming mode (PAR/SER =
V
be driven with 1.8V to 3.3V logic.
GND (Pins 22, 45, 49, Exposed Pad Pin 53): ADC Power
Ground. The exposed pad must be soldered to the PCB
ground.
OGND (Pin 33): Output Driver Ground. Must be shorted
to the ground plane by a very low inductance path. Use
multiple vias close to the pin.
OV
with a 0.1μF ceramic capacitor.
SDO (Pin 46): In serial programming mode (PAR/SER
= 0V), SDO is the optional serial interface data output.
Data on SDO is read back from the mode control reg-
isters and can be latched on the falling edge of SCK.
SDO is an open-drain N-channel MOSFET output that
requires an external 2k pull-up resistor of 1.8V to
3.3V. If readback from the mode control registers is
not needed, the pull-up resistor is not necessary and
SDO can be left unconnected. In parallel programming
DD
DD
DD
), SDI can be used to power down the part. SDI can
–
), CS selects two-lane or one-lane output mode. CS
(Pin 18): Encode Complement Input. Conversion
(Pin 34): Output Driver Supply. Bypass to ground
DD
), SCK selects 3.5mA
21721014f