LTM9001-BX_15 Datasheet, PDF (18/30 Pages) Linear Technology – 16-Bit IF/Baseband Receiver Subsystem

LTM9001-Ax/LTM9001-Bx
OPERATION
The following sections describe in further detail the func-
tional operation of the LTM9001. The SiP technology allows
the LTM9001 to be customized and this is described in
the first section. The remaining outline follows the basic
functional elements as shown in Figure 1.
ADC
AMPLIFIER
INPUT
ADC
NETWORK
9001 F01
Figure 1. Basic Functional Elements
SEMI-CUSTOM OPTIONS
The μModule construction affords a new level of flexibility in
application-specific standard products. Standard ADC and
amplifier components can be integrated regardless of their
process technology and matched with passive components
to a particular application. The LTM9001-AA, as the first
example, is configured with a 16-bit ADC sampling at rates
up to 130Msps. The amplifier gain is 20dB with an input
impedance of 200Ω and an input range of 233mV_P-P. The
matching network is designed to optimize the interface
between the amplifier output and the ADC under these
conditions. Additionally, there is a 2-pole bandpass filter
designed for 162.5MHz ±25MHz.
However, other options are possible through Linear Tech-
nology’s semi-custom development program. Linear
Technology has in place a program to deliver other speed,
resolution, IF range, gain and filter configurations for a
wide range of applications. See Table 1 for the LTM9001-AA
configuration and potential options. These semi-custom
designs are based on existing ADCs and amplifiers with
an appropriately modified matching network. The final
subsystem is then tested to the exact parameters defined
for the application. The final result is a fully integrated,
accurately tested and reliable solution. For more details
on the semi-custom receiver subsystem program, contact
Linear Technology.
Note that not all combinations of options in Table 1 are
possible at this time and specified performance may differ
significantly from existing values. This data sheet discusses
devices with LVDS and CMOS outputs. The lower speed
options that only support CMOS outputs are available on
a separate data sheet. The CMOS-only options have a
different pin assignment.
AMPLIFIER INFORMATION
The amplifiers used in the LTM9001 are low noise and low
distortion fully differential ADC drivers. The amplifiers are
very flexible in terms of I/O coupling. They can be AC- or
DC-coupled at the inputs. Users are advised to keep the
input common mode voltage between 1V and 1.6V for
proper operation. If the inputs are AC-coupled, the input
common mode voltage is automatically biased. The input
signal can be either single-ended or differential with almost
no difference in distortion performance.
Table 1. Semi-Custom Options
AMPLIFIER IF AMPLIFIER INPUT
RANGE
IMPEDANCE AMPLIFIER GAIN
FILTER
ADC SAMPLE
RATE
300MHz
200Ω
20dB
162.5MHz BPF, 50MHz BW 130Msps
300MHz
200Ω
14dB
70MHz BPF, 25MHz BW 130Msps
300MHz
400Ω
8dB
DC-300MHz LPF
160Msps
Select Combination of Options from Columns Below
DC-300MHz
50Ω
26dB
LPF TBD
160Msps
DC-140MHz
200Ω
20dB
BPF TBD
130Msps
DC-70MHz
200Ω
14dB
105Msps
DC-35MHz
400Ω
8dB
80Msps
200Ω
6dB
65Msps
40Msps
25Msps
10Msps
ADC
RESOLUTION
16-bit
16-bit
16-bit
16-bit
14-bit
OUTPUT
LVDS/CMOS
LVDS/CMOS
LVDS/CMOS
LVDS/CMOS
LVDS/CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
CMOS
PART NUMBER
LTM9001-AA
LTM9001-AD
LTM9001-BA
9001fc
18