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  5. LTC6561


Features and Benefits

  • 220MHz –3dB Bandwidth with 2pF Input Capacitance
  • Single-Ended Output
  • 74kΩ Transimpedance Gain
  • 4.8pA/√Hz Input Current Noise Density at 200MHz (2pF)
  • 64nARMS Integrated Input Current Noise Over 200MHz (2pF)
  • Linear Input Range 0µA to 30µA
  • Overload Current > ±400mA Peak
  • Fast Overload Recovery 12ns, 1mA 
  • Fast Channel Switchover < 50ns
  • Single 5V Supply
  • 200mW Power Dissipation for 4 Channels
  • 2VP-P Output Swing on 100Ω Load
  • 4mm × 4mm, 24-Lead QFN Package
  • Output MUX Combines Multiple 4-Channel Devices to Create 4, 8,12,16, 24, 32 Channel Solutions
  • AEC-Q100 Qualified for Automotive Applications

Product Details

The LTC6561 is a low-noise four-channel, transimpedance amplifier (TIA)with 220MHz bandwidth. The LTC6561 multi-channel transimpedance amplifier’s low noise, high transimpedance, and low power dissipation are ideal for LIDAR receivers using Avalanche Photodiodes (APDs). The amplifier features 74kΩ transimpedance gain and 30µA linear input current range. Using an APD input circuit with a total capacitance of 2pF, the input current noise density is 4.5pA/√Hz at 200MHz. With lower capacitance, noise and bandwidth improve further. Only a 5V single supply is needed and the device consumes only 200mW. Utilizing the internal 4-to-1 MUX along with the LTC6561’s output MUX; multiple 4-channel LTC6561 devices can be combined to directly interface with 8, 12, 16 and 32-channel APD arrays. The LTC6561’s fast overload recovery and fast channel switchover make it well suited for LIDAR receivers with multiple APDs. Its single-ended output can swing 2VP-P on a 100Ω load. While its low impedance op amp-style output can drive back-terminated 50Ω cables.

The LTC6561 is packaged in a compact 4mm × 4mm 24-pin leadless QFN package with an exposed pad for thermal management and low inductance.


  • LIDAR Receiver
  • Industrial Imaging

Product Lifecycle icon-recommended Recommended for New Designs

This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.

Evaluation Kits (2)

Tools & Simulations


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.


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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
LTC6561DICE Material Declaration Reliability Data CHIPS OR DIE
LTC6561DWF Material Declaration Reliability Data UNSAWN DIE/WAFER SALES
LTC6561HUF#PBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LTC6561HUF#TRPBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LTC6561HUF#WPBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LTC6561HUF#WTRPBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LTC6561IUF#PBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
LTC6561IUF#TRPBF Material Declaration Reliability Data 24-Lead QFN (4mm x 4mm x 0.75mm w/ EP)
Wafer Fabrication Data

Sample & Buy

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Buy Now Pricing

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Evaluation Boards

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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.