LTC1407CMSE Linear Technology, LTC1407CMSE Datasheet - Page 12

• Manufacturer Part Number: LTC1407CMSE
• Description: IC ADC 12BIT 3MSPS SAMPLE 10MSOP
• Manufacturer: Linear Technology

Specifications of LTC1407CMSE

• Number Of Bits: 12
• Sampling Rate (per Second): 3M
• Data Interface: Serial, SPI™
• Number Of Converters: 1
• Power Dissipation (max): 14mW
• Voltage Supply Source: Single Supply
• Operating Temperature: 0°C ~ 70°C
• Mounting Type: Surface Mount
• Package / Case: 10-TFSOP, 10-MSOP (0.118", 3.00mm Width) Exposed Pad
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

APPLICATIONS INFORMATION
LTC1407/LTC1407A
LT1818/LT1819: 400MHz, 2500V/μs, 9mA, Single/Dual
Voltage Mode Operational Amplifi er.
LT6200: 165MHz GBWP , –85dBc distortion at 1MHz,
unity-gain stable, rail-to-rail in and out, 15mA/amplifi er,
0.95nV/√Hz.
LT6203: 100MHz GBWP , –80dBc distortion at 1MHz,
unity-gain stable, rail-to-rail in and out, 3mA/amplifi er,
1.9nV/√Hz.
LT6600: Amplifi er/Filter Differential In/Out with 10MHz
Cutoff.
INPUT FILTERING AND SOURCE IMPEDANCE
The noise and the distortion of the input amplifi er and
other circuitry must be considered since they will add to
the LTC1407/LTC1407A noise and distortion. The small-
signal bandwidth of the sample-and-hold circuit is 50MHz.
Any noise or distortion products that are present at the
analog inputs will be summed over this entire bandwidth.
Noisy input circuitry should be fi ltered prior to the analog
12
ANALOG
ANALOG
INPUT
INPUT
*TIGHT TOLERANCE REQUIRED TO AVOID
Figure 1. RC Input Filter
APERTURE SKEW DEGRADATION
51Ω*
51Ω*
10μF
47pF*
47pF*
11
1
2
3
4
5
inputs to minimize noise. A simple 1-pole RC fi lter is
suffi cient for many applications. For example, Figure 1
shows a 47pF capacitor from CHO
source resistor to limit the net input bandwidth to 30MHz.
The 47pF capacitor also acts as a charge reservoir for the
input sample-and-hold and isolates the ADC input from
sampling-glitch sensitive circuitry. High quality capacitors
and resistors should be used since these components
can add distortion. NPO and silvermica type dielectric
capacitors have excellent linearity. Carbon surface mount
resistors can generate distortion from self heating and
from damage that may occur during soldering. Metal
fi lm surface mount resistors are much less susceptible
to both problems. When high amplitude unwanted signals
are close in frequency to the desired signal frequency a
multiple pole fi lter is required.
High external source resistance, combined with 13pF
of input capacitance, will reduce the rated 50MHz input
bandwidth and increase acquisition time beyond 39ns.
CH0
CH0
V
GND
CH1
CH1
REF
LTC1407A
LTC1407/
+
–
+
–
1407 F01
+
to ground and a 51Ω
1407fb