LTC1747 Linear Technology, LTC1747 Datasheet - Page 9

• Manufacturer Part Number: LTC1747
• Description: 12-Bit 80Msps Low Noise ADC
• Manufacturer: Linear Technology

SENSE (Pin 1): Reference Sense Pin. Ground selects 1V.
V DD selects 1.6V. Greater than 1V and less than 1.6V
applied to the SENSE pin selects an input range of V
V
Bypass to ground with 4.7 F ceramic chip capacitor.
GND (Pins 3, 6, 9, 12, 13, 16, 19, 21, 36, 37): ADC Power
Ground.
A
A
V
with 1 F ceramic chip capacitors.
REFLB (Pin 10): ADC Low Reference. Bypass to Pin 11
with 0.1 F ceramic chip capacitor. Do not connect to
Pin 14.
REFHA (Pin 11): ADC High Reference. Bypass to Pin 10 with
0.1 F ceramic chip capacitor, to Pin 14 with a 4.7 F ceramic
capacitor and to ground with 1 F ceramic capacitor.
REFLA (Pin 14): ADC Low Reference. Bypass to Pin 15 with
0.1 F ceramic chip capacitor, to Pin 11 with a 4.7 F ce-
ramic capacitor and to ground with 1 F ceramic capacitor.
REFHB (Pin 15): ADC High Reference. Bypass to Pin 14
with 0.1 F ceramic chip capacitor. Do not connect to
Pin 11.
PI FU CTIO S
1.6V is the largest valid input range.
CM
IN
IN
DD
U
+
–
(Pin 2): 2.35V Output and Input Common Mode Bias.
(Pins 7, 8, 17, 18, 20): 5V Supply. Bypass to AGND
(Pin 4): Positive Differential Analog Input.
(Pin 5): Negative Differential Analog Input.
U
U
SENSE
,
MSBINV (Pin 22): MSB Inversion Control. Low inverts
the MSB, 2’s complement output format. High does not
invert the MSB, offset binary output format.
ENC (Pin 23): Encode Input. The input sample starts on the
positive edge.
ENC (Pin 24): Encode Complement Input. Conversion
starts on the negative edge. Bypass to ground with 0.1 F
ceramic for single-ended ENCODE signal.
OE (Pin 25): Output Enable. Low enables outputs. Logic
high makes outputs Hi-Z. OE should not exceed the
voltage on 0V
CLKOUT (Pin 26): Data Valid Output. Latch data on the
rising edge of CLKOUT.
OGND (Pins 27, 38, 47): Output Driver Ground.
NC (Pins 28, 29): Do not connect these pins.
D0-D1 (Pins 30 to 31): Digital Outputs.
OV
ers. Bypass to ground with 0.1 F ceramic chip capacitor.
D2-D4 (Pins 33 to 35): Digital Outputs.
D5-D8 (Pins 39 to 42): Digital Outputs.
D9-D11 (Pins 44 to 46): Digital Outputs.
OF (Pin 48): Over/Under Flow Output. High when an over
or under flow has occurred.
DD
(Pins 32, 43): Positive Supply for the Output Driv-
DD
.
www.DataSheet4U.com
LTC1747
1747fa
9