LTC1743 Datasheet, PDF (1/24 Pages) Linear Technology – 12-Bit, 50Msps ADC

FEATURES
s _{Sample Rate: 50Msps}
s _{72.5dB SNR and 85dB SFDR (3.2V Range)}
s _{71dB SNR and 90dB SFDR (2V Range)}
s _{No Missing Codes}
s _{Single 5V Supply}
s _{Power Dissipation: 1000mW}
s _{Selectable Input Ranges: ±1V or ±1.6V}
s _{150MHz Full Power Bandwidth S/H}
s _{Pin Compatible Family}
25Msps: LTC1746 (14-Bit), LTC1745 (12-Bit)
50Msps: LTC1744 (14-Bit), LTC1743 (12-Bit)
65Msps: LTC1742 (14-Bit), LTC1741 (12-Bit)
80Msps: LTC1748 (14-Bit), LTC1747 (12-Bit)
s _{48-Pin TSSOP Package}
U
APPLICATIO S
s _{Telecommunications}
s _Receivers
s _{Cellular Base Stations}
s _{Spectrum Analysis}
s _{Imaging Systems}
, LTC and LT are registered trademarks of Linear Technology Corporation.
LTC1743
12-Bit, 50Msps ADC
DESCRIPTIO
The LTC^®1743 is a 50Msps, sampling 12-bit A/D con-
verter designed for digitizing high frequency, wide
dynamic range signals. Pin selectable input ranges of ±1V
and ±1.6V along with a resistor programmable mode
allow the LTC1743’s input range to be optimized for a
wide variety of applications.
The LTC1743 is perfect for demanding communications
applications with AC performance that includes 72.5dB
SNR and 85dB spurious free dynamic range. Ultralow jitter
of 0.3ps_RMS allows undersampling of IF frequencies with
excellent noise performance. DC specs include ±1LSB
maximum INL and ±0.8LSB DNL over temperature.
The digital interface is compatible with 5V, 3V and 2V logic
systems. The ENC and ENC inputs may be driven differen-
tially from PECL, GTL and other low swing logic families or
from single-ended TTL or CMOS. The low noise, high gain
ENC and ENC inputs may also be driven by a sinusoidal
signal without degrading performance. A separate output
power supply can be operated from 0.5V to 5V, making it
easy to connect directly to any low voltage DSPs or FIFOs.
The 48-pin TSSOP package with a flow-through pinout
simplifies the board layout.
BLOCK DIAGRA
A_IN+
±1V
DIFFERENTIAL
ANALOG INPUT _AIN–
SENSE
V_CM
4.7µF
RANGE
SELECT
2.5V_REF
50Msps, 12-Bit ADC with a 2V Differential Input Range
OV_DD
0.1µF
0.5V TO 5V
0.1µF
S/H
12-BIT
AMP
PIPELINED ADC
BUFFER
DIFF AMP
12
OUTPUT
LATCHES
OF
•••
D11
D0
CLKOUT
OGND
CONTROL LOGIC
V_DD
5V
1µF
1µF
1µF
GND
REFLB
0.1µF
1µF
REFHA
4.7µF
REFLA REFHB ENC ENC MSBINV
0.1µF DIFFERENTIAL
1µF
ENCODE INPUT
1743 BD
OE
1743f
1