LTC6409CUDB#TRMPBF

Overview

The LTC6409CUDB#TRMPBF is a high-speed, low-distortion differential amplifier designed for driving analog-to-digital converters. It features a 10GHz gain-bandwidth product and an input noise density of 1.1nV/√Hz. The device operates on a supply voltage range of 2.7V to 5.25V, drawing 52mA in active mode and 100µA in shutdown. It supports a differential slew rate of 3300V/µs and includes hardware shutdown functionality. The component is housed in a compact 3mm × 2mm 10-lead QFN package and is specified for operation from 0°C to 70°C.

Feature Summary

• Fully differential architecture with adjustable output common mode voltage
• Input common mode range includes ground for DC-coupled single-ended inputs
• External resistors set gain with minimum stable differential gain of 1 V/V
• Hardware shutdown feature reduces power consumption significantly

Applications

• Differential pipeline ADC driver
• High speed data-acquisition cards
• Automated test equipment
• Time domain reflectometry
• Communications receivers

Procurement Notes

Verify the specific temperature grade suffix matches application requirements. The CUDB variant is rated for 0°C to 70°C, while IUDB covers -40°C to 85°C and HUDB covers -40°C to 125°C. Confirm the TRMPBF suffix indicates the mini tape and reel packaging format containing 500 pieces. Ensure the lead-free finish designation aligns with environmental compliance standards required by the end product.

Selection Notes

Select this component when driving differential ADCs requires a wide bandwidth and low noise performance. The ability to DC-couple ground-referenced signals simplifies interface design. Consider the external gain setting flexibility for custom frequency response tailoring. Evaluate the shutdown current reduction if power management during idle states is critical. Verify that the 3mm x 2mm package fits within the available PCB area constraints.

Part Context

This part belongs to the LTC6409 family of wideband differential amplifiers manufactured by Analog Devices Inc. The family shares core architectural features but differs in temperature ranges and packaging options. The CUDB variant represents the commercial temperature grade version. It is optimized for applications requiring precise phase balancing and even-order harmonic distortion cancellation.

Replacement Considerations

Direct substitutes include the LTC6409IUDB#TRMPBF for wider industrial temperature range (-40°C to 85°C) and the LTC6409HUDB#TRMPBF for extended military/industrial range (-40°C to 125°C). All variants share identical pinouts and electrical characteristics within their respective operating temperatures. Verify thermal management requirements if upgrading to higher temperature grades.

FAQ

How is the output common mode voltage determined?

The output common mode voltage is set by the voltage applied to the VOCM pin. If left floating, an internal resistor divider sets a default voltage of 1.25V with a 5V supply.

What is the minimum stable differential gain?

The LTC6409 is stable at a differential gain of 1 V/V, allowing for low output noise in applications where no gain is desired.

How does the SHDN pin control power consumption?

Connecting the SHDN pin to V– disables the amplifier, reducing supply current to approximately 100µA. Leaving it open or tying it to V+ maintains normal active operation with 52mA consumption.