LTC6420IUDC-20#TRPBF

Overview

The LTC6420IUDC-20#TRPBF is a dual high-speed differential amplifier and ADC driver from Analog Devices, packaged in a 20-lead 3mm × 4mm QFN. It features a fixed gain of 10V/V (20dB) with a 1.8GHz -3dB bandwidth. The device operates on a supply voltage range of 2.85V to 3.5V, drawing 80mA per amplifier. Key electrical specifications include a slew rate of 4500 V/μs, an input offset voltage of ±0.4mV, and a noise figure of 6.2dB at 100MHz. It supports DC or AC coupling and includes independent enable pins for shutdown control.

Feature Summary

• Dual matched amplifiers with channel-to-channel gain matching of ±0.1dB and phase matching of ±0.1° at 100MHz.
• Integrated output common mode voltage control via external VOCM pin, eliminating the need for transformers or AC-coupling capacitors.
• Rail-to-rail output swing capability with low distortion performance suitable for driving high-resolution ADCs.
• Independent logic-controlled enable pins allow for individual channel shutdown to reduce power consumption.

Applications

• Differential ADC Driver
• Single Ended to Differential Conversion
• IF Sampling (Diversity) Receivers
• Broadband I/Q Amplifiers
• Satellite Communications

Procurement Notes

Verify the specific suffix #TRPBF indicates tape and reel packaging rather than tube. Confirm the 'I' grade designation matches the required operating temperature range of –40°C to 85°C. Ensure the component source is authorized to prevent counterfeit parts, as this is a specialized high-frequency analog device.

Selection Notes

Select this part when a dual-channel solution with precise gain and phase matching is required for broadband applications. It is optimized for driving 12-, 14-, and 16-bit ADCs directly. Consider the 200Ω differential input impedance and fixed 20dB gain when designing the signal chain. Verify that the 3V supply voltage aligns with the system power architecture.

Part Context

This component belongs to the LTC6420-20 family of dual matched differential amplifiers. It shares the same core architecture and specifications as the LTC6420CUDC-20 but differs in the industrial temperature grade. The 'I' suffix denotes operation from –40°C to 85°C, whereas the 'C' variant is rated for 0°C to 70°C.

Replacement Considerations

LTC6420CUDC-20#TRPBF

FAQ

How is the output common mode voltage determined?

The output common mode voltage is set by an external voltage applied to the VOCM pin, which can be adjusted between 1.1V and 1.6V.

What is the differential input impedance?

The differential input impedance is nominally 200Ω.