Skyworks Solutions Inc. SL28EB740AZI

Overview

SL28EB740AZI from Silicon Labs is a programmable EProClock® clock generator optimized for Intel Tunnel Creek and Top Cliff platforms, delivering differential CPU clocks (up to 166 MHz), 100 MHz SRC outputs, 75/100 MHz SATA clocks, 96 MHz DOT, 48/12 MHz USB, 14.318 MHz, and 25 MHz reference clocks - all with I²C programmability, spread-spectrum control, and Wake-on-LAN support.

For engineers reviewing the SL28EB740AZI datasheet, SL28EB740AZI pinout, SL28EB740AZI application, or SL28EB740AZI equivalent, this device serves as a CK505-compliant, industrial-grade (–40°C to +85°C), 56-pin TSSOP timing solution for embedded x86 compute platforms requiring precise multi-output clock synthesis with dynamic output enable, slew rate tuning, and low-power stop modes.

Technical Context

The SL28EB740AZI integrates four independent PLLs - three non-SSC and one SSC-enabled - supporting simultaneous generation of CPU, SRC, SATA, DOT, PCI, and USB clocks from a single 25 MHz crystal or external clock input. Its EProClock® non-volatile configuration allows factory-programmed frequency sets, differential skew/duty cycle/amplitude control, and per-output enable/disable via SMBus.

It implements hardware-strapped and SMBus-configurable frequency selection (via FS[3:0] pins), supports synchronous clock stopping via CPU_STP# and PCI/SRC_STP#, and features dual-function CKPWRGD/PD# for power-down sequencing. All differential outputs comply with Intel CK505 AC/DC specifications including <100 ps cycle-to-cycle jitter and ±100 ppm long-term accuracy.

Key Specifications

Pinout & Package

SL28EB740AZI is housed in a 56-pin Thin Shrink Small Outline Package (TSSOP) with 0.5 mm pitch, thermally enhanced for industrial compute applications. Pin assignments are fully defined in the official Silicon Labs SP-AP-0006 Rev. AC documentation.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICS9LPRS495AKLFT and PI6C557-03LEX, the SL28EB740AZI uniquely combines Intel CK505 compliance, EProClock® field-programmability, WOL-ready 25 MHz reference, and full differential output flexibility - making it irreplaceable for validated Tunnel Creek/Top Cliff platform designs requiring timing adaptability and industrial reliability.

Availability

SL28EB740AZI is available at Aetrix Electronics and suitable for Intel Atom-based industrial PCs, embedded network appliances, medical imaging terminals, and transportation infotainment systems requiring stable component supply, long-lifecycle support, and CK505-compliant timing performance.

Supply support for SL28EB740AZI 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

Silicon Labs is a fabless semiconductor company specializing in timing, wireless, and MCU solutions for embedded systems, with leadership in programmable clock technology and energy-efficient mixed-signal ICs.

The SL28EB740AZI belongs to Silicon Labs' EProClock® family - engineered specifically for Intel Atom processor platforms to deliver CK505-compliant, software-configurable, low-jitter clock synthesis with industrial-grade reliability and EMI mitigation.

FAQ

What is the primary function of the SL28EB740AZI in Intel Tunnel Creek and Top Cliff platforms?

The SL28EB740AZI serves as the central clock generator for Intel Tunnel Creek and Top Cliff platforms, synthesizing and distributing multiple synchronized clock domains - including differential CPU (up to 166 MHz), SRC (100 MHz), SATA (75/100 MHz), DOT (96 MHz), USB (48/12 MHz), and reference (25 MHz/14.318 MHz) clocks - all compliant with Intel CK505 specifications. Its EProClock® programmability enables precise tuning of output characteristics without hardware modification.

Does the SL28EB740AZI support spread-spectrum clocking, and how is it configured?

Yes, the SL28EB740AZI supports triangular spread-spectrum clocking (SSC) on CPU, SRC, and PCI outputs with a default modulation depth of –0.5%. Spread enable is controlled via Bit 5 of Control Register 0 (Spread Enable), accessible through the SMBus interface. The SSC profile is non-volatile and can be programmed during manufacturing or system initialization - no runtime reconfiguration is required once set.

How does the SL28EB740AZI implement Wake-On-LAN functionality?

The SL28EB740AZI supports Wake-On-LAN by maintaining its 25 MHz reference clock output during system suspend states (S3/S4) when the WOL_EN bit (Byte 1, Bit 1) is set to "1". This occurs even when only VDD_SUSPEND is powered - enabling network controllers to remain operational for remote wake events. When WOL_EN = 0, the CKPWRGD/WOL_STP#/PD# pin functions solely as a power-down signal.

Can the SL28EB740AZI generate both 75 MHz and 100 MHz SATA clocks, and how is the selection made?

Yes, the SL28EB740AZI generates either 75 MHz or 100 MHz SATA clocks on the SATA75M/SRC0 differential pair. Selection is controlled by the SEL_SATA75 pin (Pin 5): logic low selects 100 MHz, logic high selects 75 MHz. This hardware-strapped option is sampled at CKPWRGD assertion and cannot be changed dynamically - ensuring deterministic SATA clock behavior at boot.

What package type and thermal characteristics does the SL28EB740AZI use?

The SL28EB740AZI uses a 56-pin TSSOP package with 0.5 mm pitch and JEDEC-standard thermal metrics: θJA = 60°C/W and θJC = 20°C/W. It operates across the industrial temperature range of –40°C to +85°C ambient, with maximum junction temperature rated at 150°C. Power dissipation is managed via configurable output enables and low-power stop modes, keeping typical IDD below 115 mA under full load.