Diodes Incorporated PI6CG18201ZDIEX

Overview

PI6CG18201 from Diodes Incorporated is a 2-output, very low power PCIe Gen1–Gen4 clock generator with on-chip HCSL termination, 1.8V supply, 25MHz crystal/CMOS input, and 100MHz differential outputs. It integrates a proprietary PLL for sub-50ps cycle-to-cycle jitter and supports spread-spectrum modulation (0%, –0.25%, or –0.5%) to reduce EMI in high-speed server and storage platforms.

For engineers reviewing the PI6CG18201 datasheet, PI6CG18201 pinout, PI6CG18201 application, or PI6CG18201 equivalent, key selection criteria include PCIe Gen4 compliance, integrated 33Ω HCSL termination per output, SMBus/strapping configurability, 1.8V analog/digital supplies, and <1.5ps RMS phase jitter on the REFOUT.

Technical Context

The PI6CG18201 employs a fully integrated PLL architecture optimized for PCIe timing budgets, locking to a 25MHz fundamental-mode crystal or CMOS reference and generating two independent 100MHz low-power HCSL clocks. Its analog PLL core uses voltage-controlled oscillator (VCO) and charge-pump feedback to achieve <0.5ps integrated phase jitter (RMS) for PCIe Gen4 Common Clock Architecture.

Each HCSL output pair (Q0±, Q1±) features programmable slew rate (via SMBus or strapping), amplitude control (0.6–0.9V), and individual enable/disable via OE0# and OE1#. The device also provides a buffered 100MHz LVCMOS REFOUT with <1.5ps RMS phase jitter and configurable slew rate, plus tri-level SS_SEL_TRI for hardware-selectable spread-spectrum at power-up.

Key Specifications

Pinout & Package

PI6CG18201 is housed in a 24-lead, 4×4 mm TQFN package with exposed thermal pad (pin 24 = GND_XTAL). Pin assignments are validated per Diodes DS39996 Rev 6-2.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar PCIe clock generator applications.

Compared with IDT 9FGV1006A and Microchip SY89467L, the PI6CG18201 uniquely delivers dual HCSL outputs with on-chip termination, 1.8V operation, and spread-spectrum capability - reducing component count by 8 resistors and enabling PCIe Gen4-compliant timing in thermally constrained, EMI-sensitive platforms.

Availability

PI6CG18201 is available at Aetrix Electronics and suitable for PCIe Gen4 server backplanes, enterprise NVMe SSD controllers, AI accelerator modules, and industrial embedded systems requiring stable component supply across multi-year production cycles.

Supply support for PI6CG18201 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 timing, power management, and signal integrity solutions for computing, communications, and industrial markets.

The PI6CG18201 belongs to Diodes' PCIe-optimized clock generator product line, designed specifically to meet Gen4 timing margins while minimizing power, board space, and EMI in high-density data center and storage applications.

FAQ

What is the minimum startup time from power-on to stable 100MHz HCSL output?

The PI6CG18201 achieves full lock and stable 100MHz differential output within 20 ms after PD# de-assertion, with clock stabilization complete by 1.8 ms after input clock stability or PD# release. This includes internal PLL lock time and output enable latency of 1–3 clock cycles after OE# assertion.

Can the REFOUT be used simultaneously as an SMBus address pin?

No - SADR/REFOUT is a multiplexed pin that operates in one mode only: either as SMBus address select (when configured via strapping at power-up) or as 1.8V LVCMOS REFOUT buffer. The function is latched at power-on and cannot be dynamically switched during operation.

How does the on-chip HCSL termination affect PCB layout compared to discrete termination?

The integrated 33Ω termination eliminates eight 0402/0603 resistors and their associated vias and routing, reducing layer count by 1–2, shortening differential trace lengths by up to 15mm, and removing impedance discontinuities caused by resistor pads - directly improving insertion loss and return loss above 5 GHz.

Is the PI6CG18201 qualified for automotive applications?

No - the PI6CG18201 is specified for industrial temperature range (–40°C to +85°C) and is not AEC-Q100 qualified. Diodes offers separate automotive-grade variants (e.g., PI6CG18201Q) with PPAP support, IATF 16949 manufacturing, and extended qualification testing for automotive use.