Diodes Incorporated PI6CBF18501ZLAIEX

Overview

PI6CBF18501 from Diodes Incorporated is a 5-output, very low power PCIe Gen1–Gen4 fanout buffer with HCSL input and five differential low-power HCSL outputs featuring on-chip 50Ω termination, 1.8V supply, and individual output enable control. It delivers <50ps differential cycle-to-cycle jitter and <50ps output-to-output skew for high-speed server, storage, and AI accelerator clock distribution.

For engineers reviewing the PI6CBF18501 datasheet, PI6CBF18501 pinout, PI6CBF18501 application, or PI6CBF18501 equivalent, key selection criteria include PCIe Gen4-compliant additive phase jitter (≤0.05ps RMS), programmable slew rate/amplitude per output via SMBus, 3.3V-tolerant SMBus interface, and industrial temperature support (–40°C to +85°C).

Technical Context

The PI6CBF18501 implements a fully differential HCSL signal path with separate analog (VDDA/VDD_R) and digital (VDD_DIG/VDD) power domains, enabling precise noise isolation. Its proprietary architecture achieves sub-5ps additive cycle-to-cycle jitter at 100MHz while maintaining <1% duty cycle distortion across all outputs.

Each of the five HCSL output pairs (Q0–Q4) features independent OE# pins and SMBus-configurable amplitude (0.6–0.9V) and slew rate (1.1–4.0 V/ns), allowing board-level optimization without hardware changes. The device supports dual SMBus address options (1101011b / 1101100b) latched at power-up via SADR_TRI.

Key Specifications

Pinout & Package

Package: 40-lead, 5×5mm, 0.5mm pitch Very Thin Quad Flat No-Lead (TQFN, ZLA code). Exposed pad (EPAD) must be connected to GND for thermal and electrical integrity.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe fanout buffer applications.

Compared with IDT8T49N242 and Si53302-A01, the PI6CBF18501 uniquely balances 5-output count, on-chip termination, PCIe Gen4 jitter compliance, and per-output configurability - making it optimal for mid-density server/storage clock trees where BOM simplification and skew control are critical.

Availability

PI6CBF18501 is available at Aetrix Electronics and suitable for server motherboard design, AI accelerator timing, and enterprise storage controller development requiring stable component supply, long-term lifecycle assurance, and industrial-grade reliability.

Supply support for PI6CBF18501 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

Diodes Incorporated is a global manufacturer of discrete semiconductors and integrated circuits, specializing in high-performance analog, logic, and timing solutions for industrial, computing, and communications markets.

The PI6CBF18501 belongs to Diodes' Pericom-branded PCIe timing portfolio, engineered specifically for low-jitter, low-power clock distribution in next-generation data center and AI infrastructure where signal integrity and power efficiency are co-optimized.

FAQ

What is the function of the SADR_TRI pin?

The SADR_TRI pin is a tri-level input that selects one of two SMBus slave addresses (1101011b or 1101100b) at power-up. When pulled low, it latches the first address; when pulled high, it latches the second; when left floating (via internal pull-down), it defaults to the first. This enables multiple PI6CBF18501 devices on a shared SMBus without address conflict.

How does the on-chip termination reduce design complexity?

The PI6CBF18501 integrates 50Ω series termination on each HCSL output pair, eliminating the need for 24 external 50Ω resistors (4 per differential pair). This reduces PCB layer count, minimizes stub effects, improves impedance matching, and cuts assembly cost - verified to maintain <50ps output-to-output skew without layout tuning.

Can the SMBus interface operate at 3.3V while the core runs at 1.8V?

Yes. The SMBus pins (SCLK and SDATA) are explicitly rated for 3.3V tolerance per datasheet Section 6, supporting direct connection to 3.3V host controllers without level shifters. Internal voltage translation ensures reliable communication even when VDD_DIG = 1.8V and SMBus VDD = 3.3V, with VIH ≥2.1V and VIL ≤0.6V thresholds.

What happens to outputs during PD# assertion?

When PD# is driven low, all five HCSL outputs immediately transition to a forced LOW/LOW state (not high-impedance), and internal circuitry enters ultra-low-power mode drawing <0.8mA total. Upon PD# de-assertion, outputs re-enable after 20–300μs latency, with full clock stabilization occurring within 2ms - verified across –40°C to +85°C.