Analog Devices Inc. LT5511EFE#PBF

Overview

LT5511EFE#PBF from Analog Devices (formerly Linear Technology) is a high-linearity, upconverting double-balanced mixer IC designed for CATV downstream transmitters and wireless infrastructure transmit systems. It delivers +17dBm IIP3 at 950MHz, +15.5dBm IIP3 at 1900MHz, and +6dBm input 1dB compression point with 56–65mA supply current across 4.0–5.25V operation.

For engineers reviewing the LT5511EFE#PBF datasheet, LT5511EFE#PBF pinout, LT5511EFE#PBF application, or LT5511EFE#PBF equivalent, key selection criteria include broadband RF output (10–3000MHz), integrated LO buffer requiring only –10dBm drive, differential IF/LO/RF ports, enable-controlled shutdown (1–30µA), and 16-pin TSSOP exposed-pad package thermal performance.

Technical Context

The LT5511EFE#PBF integrates a differential limiting LO buffer driving a double-balanced active mixer core, enabling single-ended LO drive without balun. Its IF input stage uses emitter-coupled transistor pairs biased at ~1.2V, requiring external 75Ω termination resistors for optimal linearity and LO suppression.

RF output is differential and collector-driven, supporting center-tap transformer biasing or series inductor matching to 200Ω for 4:1 balun interfacing. The LO buffer operates over 30–2700MHz, while RF output spans 10–3000MHz and IF input covers 1–300MHz - all validated with external matching networks per Figure 2/3 test circuits.

Key Specifications

Pinout & Package

LT5511EFE#PBF is housed in a 16-lead plastic TSSOP with exposed pad (FE package), measuring 4.4mm × 5.0mm. The exposed pad must be soldered to PCB ground for thermal dissipation (θ_JA = 38°C/W) and RF return path integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar upconverting mixer applications.

Compared with LT5511EFE#PBF, LT5512EFE#PBF serves opposite signal direction (downconversion), while ADL5801ACPZ-R7 offers wider bandwidth and higher linearity at the cost of package size, thermal profile, and design complexity - making LT5511EFE#PBF optimal for cost-sensitive, thermally constrained CATV/wireless upconverters.

Availability

LT5511EFE#PBF is available at Aetrix Electronics and suitable for CATV infrastructure, wireless base station transmitters, and high-linearity test equipment requiring stable component supply, long-term lifecycle support, and traceable sourcing for production programs.

Supply support for LT5511EFE#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and RF ICs for precision signal processing applications.

The LT5511EFE#PBF belongs to Linear Technology's high-linearity RF mixer product line, engineered specifically for broadband infrastructure upconversion where spectral purity, power efficiency, and thermal robustness are critical in 24/7 operational environments.

FAQ

What is the recommended LO drive level for LT5511EFE#PBF?

The LT5511EFE#PBF is specified for –10dBm differential LO input power, which fully saturates its integrated LO buffer and maximizes linearity. Driving below –15dBm or above –5dBm degrades IIP3 and conversion gain. Single-ended LO drive is supported using LO+ with LO– grounded via DC-blocking capacitor, maintaining performance within 0.5dB of differential mode.

Can LT5511EFE#PBF operate at 2.4GHz RF output frequency?

Yes, LT5511EFE#PBF supports RF output frequencies up to 3000MHz, including 2.4GHz. Figure 6 in the datasheet validates operation at 2.4GHz with 300MHz IF input, showing –7dB conversion gain and >17dBm IIP3. External matching components (e.g., 12pF C2, 5.2nH L1) must be adjusted per application layout and board parasitics.

How should the exposed pad of LT5511EFE#PBF be connected?

The exposed pad of LT5511EFE#PBF must be soldered to a solid, low-impedance PCB ground plane. It serves as the primary thermal path (θ_JA = 38°C/W) and RF ground reference. Thermal vias (≥4× 0.3mm diameter) should connect the pad to inner ground layers. Floating or unconnected pads cause thermal runaway and degraded RF performance.

What is the purpose of separate VCCLO and VCCBIAS pins on LT5511EFE#PBF?

VCCLO powers only the high-speed LO buffer amplifier, while VCCBIAS supplies the bias circuitry and enable logic. Separating these rails prevents LO switching noise from modulating the bias network, preserving LO suppression and conversion gain stability. Both pins require individual 0.1µF RF bypass capacitors placed ≤2mm from the pin.

Does LT5511EFE#PBF support low-side or high-side LO injection?

Yes, LT5511EFE#PBF supports both low-side and high-side LO injection configurations. Its double-balanced architecture and broadband port matching allow flexible LO placement - e.g., 900MHz LO + 50MHz IF yields 950MHz RF (high-side) or 850MHz RF (low-side). Performance metrics (IIP3, gain, LO leakage) remain consistent across both modes per datasheet characterization.