Overview
Features and Benefits
- Up to 10MHz Center Frequency on a Single 3V Supply
- Easy to Use—A Single Resistor Value Sets Lowpass Cutoff Frequency (200kHz < fC < 5MHz), Unequal Resistor Values Extend Cutoff Frequency Up to 10MHz
- Extremely Flexible—Different Resistor Values Allow Lowpass Transfer Functions with or Without Gain
- SNR = 92dB (fC = 2MHz, 2VP-P)
- THD = –84dB (fC = 2MHz, 1VP-P)
- Internal Capacitors Trimmed to ±0.75%
- Single 4-Pole Lowpass Filter or Matched Pair of 2-Pole Lowpass Filters
- Can be Connected as a Bandpass Filter
- Single-Ended or Differential Output
- Operates from Single 3V (2.7V Min) to ±5V Supply
- Rail-to-Rail Input and Output Voltages
Product Details
The LT1568 is an easy-to-use, active-RC filter building block with rail-to-rail inputs and outputs. The internal capacitors of the IC and the GBW product of the internal low noise op amps are trimmed such that consistent and repeatable filter responses can be achieved. With a single resistor value, the LT1568 provides a pair of matched 2-pole Butterworth lowpass filters with unity gain suitable for I/Q channels.
By using unequal-valued external resistors, the two 2-pole sections can create different frequency responses or gains. In addition, the two stages may be cascaded to create a single 4-pole filter with a programmable response. Capable of cutoff frequencies up to 10MHz, the LT1568 is ideal for antialiasing or channel filtering in high speed data communications systems. The LT1568 can also be used as a bandpass filter.
The LT1568 features very low noise, supporting signal-to-noise ratios of over 90dB. It also provides single-ended to differential signal conversion for directly driving high speed A/D converters. The LT1568 has a shutdown mode that reduces supply current to approximately 0.5mA on a 5V supply.
The LT1568 is available in a narrow 16-lead SSOP package.
Applications
- Replaces Discrete RC Active Filters and LC Filter Modules
- Antialiasing/Reconstruction Filters
- Dual or I-and-Q Channels (Two Matched 2nd Order Filters in One Package)
- Single-Ended to Differential Conversion
- Video Signal Processing
Product Categories
Product Lifecycle
Production
At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.
Evaluation Kits (1)
Documentation & Resources
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R460 Reliability Data3/23/2018
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DC675C - Demo Manual (Rev. A)4/13/2015
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LT1568 Filter Design Guide9/1/2005
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High Speed Amplifiers/ADC Drivers4/29/2015
Tools & Simulations
LTspice
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.

LTspice Simulations
Models for the following parts are available in LTspice:
Design Resources
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.View our quality and reliability program and certifications for more information.
Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
---|---|---|---|---|
LT1568CGN#PBF | Material Declaration | Reliability Data | 16-Lead SSOP (Narrow 0.15 Inch) | |
LT1568CGN#TRPBF | Material Declaration | Reliability Data | 16-Lead SSOP (Narrow 0.15 Inch) | |
LT1568IGN#PBF | Material Declaration | Reliability Data | 16-Lead SSOP (Narrow 0.15 Inch) | |
LT1568IGN#TRPBF | Material Declaration | Reliability Data | 16-Lead SSOP (Narrow 0.15 Inch) | |
Wafer Fabrication Data | R460 Reliability Data |
PCN-PDN Information
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Support & Discussions
LT1568 Discussions
Sample & Buy
Ordering FAQs
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Buy Now Pricing
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List Pricing
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Lead Times
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Sampling
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Evaluation Boards
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Up to two boards can be purchased through Analog.com. To order more than two, please purchase through one of our listed distributors.
Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.