Renesas QLX4600SIQT7

Overview

QLX4600SIQT7 from Intersil (now Renesas) is a quad-channel receive-side equalizer IC for high-speed serial links, supporting up to 6.25 Gb/s line rates with CML I/O, 32-level programmable per-channel equalization, 30 m reach on 24 AWG twin-axial cable, and individual channel power-down for PCIe applications.

For engineers reviewing the QLX4600SIQT7 datasheet, QLX4600SIQT7 pinout, QLX4600SIQT7 application, or QLX4600SIQT7 equivalent, this device delivers deterministic signal restoration in DisplayPort v1.2, InfiniBand SDR/DDR, PCI Express Gen 1/2, and 10GBase-CX4 active cable assemblies - with no adaptation latency, full protocol-aware line silence preservation, and dual control modes (pin-selectable or serial bus).

Technical Context

The QLX4600SIQT7 implements four independent Current Mode Logic (CML) receive channels, each featuring a fixed-coefficient, non-adaptive equalizer followed by a limiting amplifier. Its architecture avoids closed-loop adaptation, enabling immediate signal fidelity restoration from the first bit at data rates from 2.5 to 6.25 Gb/s.

Each channel supports dual configuration paths: three CMOS control pins (CP[k][A,B,C]) for 18 discrete boost levels, or a 4-wire serial interface (DI/DO/CLK/ENB) for full 32-level register-based programming. Input impedance can be switched between 50 Ω (active) and >200 kΩ (power-down) via dedicated IS[k] pins, directly supporting PCIe Fundamental Reset signaling.

Key Specifications

Pinout & Package

QLX4600SIQT7 is housed in a RoHS-compliant 46-lead TQFN package (4 mm × 7 mm, 0.4 mm pitch) with exposed thermal pad. Pin assignments are validated per FN6979 Rev 2.00 datasheet, Page 3–4.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar quad-channel receive equalizer applications.

Compared with ISL36411 and QLX4600-SL30, QLX4600SIQT7 uniquely balances protocol-aware line silence, flexible DT threshold control, and PCIe-compatible power-down - making it the optimal choice for multi-standard active cable designs requiring interoperability across DisplayPort, InfiniBand, and PCIe.

Availability

QLX4600SIQT7 is available at Aetrix Electronics and suitable for DisplayPort v1.2 active cable modules, InfiniBand SDR/DDR interconnects, and 10GBase-CX4 data center cabling requiring stable component supply, long-term lifecycle support, and traceable sourcing.

Supply support for QLX4600SIQT7 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

Renesas Electronics (formerly Intersil) is a global semiconductor leader specializing in analog, mixed-signal, and power management ICs for high-performance computing, communications, and industrial systems.

The QLX4600-S30 product line was designed specifically for high-density, low-power quad-lane extension in active copper cable assemblies - targeting DisplayPort, PCIe, and InfiniBand ecosystems with deterministic equalization and protocol-aware signal integrity.

FAQ

What is the maximum supported data rate for QLX4600SIQT7?

The QLX4600SIQT7 supports line rates up to 6.25 Gb/s NRZ, fully compliant with DisplayPort v1.2 HBR2, PCI Express Gen 2, InfiniBand DDR, and 10GBase-CX4. It also operates reliably at lower rates including 2.5, 3.125, 4.25, and 5 Gb/s - with consistent equalization performance across the entire range.

Does QLX4600SIQT7 support line silence preservation for InfiniBand and PCIe protocols?

Yes, QLX4600SIQT7 actively preserves line silence (electrical idle) by muting its differential outputs to <20 mV_P-P when input amplitude falls below the DT pin threshold. This maintains InfiniBand quiescent state and PCIe Electrical Idle Exit sequence integrity - a key differentiator versus conventional limiting amplifiers.

How many equalization levels does QLX4600SIQT7 offer, and how are they configured?

QLX4600SIQT7 provides 32 equalization levels per channel when programmed via its serial interface (DI/DO/CLK/ENB), or 18 levels when set using external CP[k][A,B,C] control pins. The serial mode enables full flexibility and daisy-chaining; the pin mode offers board-level simplicity with no host controller dependency.

What is the power consumption of QLX4600SIQT7 per channel and in total?

QLX4600SIQT7 consumes 78 mW per channel under typical operation at 1.2 V, totaling 312 mW for all four channels. When a channel is powered down via its IS[k] pin, current draw drops from 50 mA to 3.8 mA - reducing per-channel power to ~4.6 mW and enabling dynamic power optimization in multi-lane systems.

What package type and thermal characteristics does QLX4600SIQT7 use?

QLX4600SIQT7 uses a 46-lead TQFN package (4 mm × 7 mm, 0.4 mm pitch) with exposed thermal pad. Its thermal resistance is θ_JA = 32°C/W and θ_JC = 2.3°C/W. The exposed pad must be soldered to the PCB ground plane to ensure proper thermal dissipation and maintain junction temperature ≤125°C under full-load conditions.