High Linearity Differential RF/IF Amplifier/ADC Driver

The LTC6430-20 is a differential gain block amplifier designed to drive high resolution, high speed ADCs with excellent linearity beyond 1000MHz and with low associated output noise. The LTC6430-20 operates from a single 5V power supply and consumes only 850mW.

In its differential configuration, the LTC6430-20 can directly drive the differential inputs of an ADC. Using 1:2 baluns, the device makes an excellent 50Ω wideband balanced amplifier. While using 1:1.33 baluns, the device creates a high fidelity 40MHz to 1000MHz 75Ω CATV amplifier.

The LTC6430-20 is designed for ease of use, requiring a minimum of support components. The device is internally matched to 100Ω differential source/load impedance. On-chip bias and temperature compensation ensure consistent performance over environmental changes.

The LTC6430-20 uses a high performance SiGe BiCMOS process for excellent repeatability compared with similar GaAs amplifiers. All A-grade LTC6430-20 devices are tested and guaranteed for OIP3 at 380MHz. The LTC6430-20 is housed in a 4mm × 4mm, 24-lead, QFN package with an exposed pad for thermal management and low inductance. A single-ended 50Ω IF gain block with similar performance is also available, see the related LTC6431-20.

Applications

* Differential ADC Driver

* Differential IF Amplifier

* OFDM Signal Chain Amplifier

* 50Ω Balanced IF Amplifier

* 75Ω CATV Amplifier

* 700MHz to 800MHz LTE Amplifier

* Low Phase Noise Clock or LO Amplifier

* 51.0dBm OIP3 at 240MHz into a 100Ω Diff Load

* NF = 2.9dB at 240MHz

* 20MHz to 2060MHz –3dB Bandwidth

* 20.8dB Gain

* A-Grade 100% OIP3 Tested at 380MHz

* 0.6nV/√Hz Total Input Noise

* S11 < –10dB Up to 1.4GHz

* S22 < –10dB Up to 1.4GHz

* >2.75VP-P Linear Output Swing

* P1dB = 24.0dBm

* Insensitive to VCC Variation

* 100Ω Differential Gain-Block Operation

* Input/Output Internally Matched to 100Ω Diff

* Single 5V Supply

* DC Power = 850mW

* 4mm × 4mm, 24-Lead QFN Package