Texas Instruments CDCEL925PWR

Overview

CDCEL925PWR from Texas Instruments is a programmable 2-PLL, 5-output LVCMOS clock generator optimized for low-power 1.8V systems. It delivers up to five independent output clocks (Y1–Y5) at frequencies up to 230MHz, supports spread-spectrum clocking (SSC) for EMI reduction, and features integrated nonvolatile EEPROM for in-system configuration storage. It targets video/audio timing, USB/IEEE1394 interfaces, and TI DaVinci™/OMAP™ platforms.

For engineers reviewing the CDCEL925PWR datasheet, CDCEL925PWR pinout, CDCEL925PWR application, or CDCEL925PWR equivalent, key selection criteria include its 1.8V VDDOUT supply, ±150ppm VCXO pulling range, 100ps typical peak-to-peak period jitter (CDCEL925), TSSOP-16 package compatibility, and I²C-based SDA/SCL programming interface.

Technical Context

The CDCEL925PWR implements two independent, configurable PLLs with automatic loop filter tuning based on VCO frequency and divider settings. Each PLL supports center-spread or down-spread SSC modulation, enabling EMI suppression without external components.

It accepts input via external crystal (8–32MHz) or single-ended LVCMOS clock (up to 160MHz), with on-chip programmable load capacitance (0–20pF) and selectable VCXO mode for synchronization to PWM control signals. All five LVCMOS outputs share a dedicated 1.8V VDDOUT supply rail.

Key Specifications

Pinout & Package

Packaged in 16-pin TSSOP (PW), 5.00mm × 4.40mm footprint, with exposed pad not electrically connected. Pinout supports dual-function SDA/S1 and SCL/S2 pins, three dedicated control inputs (S0/S1/S2), and separate VDD/VDDOUT supplies.

Key Features

Applications

Equivalent & Alternatives

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

Compared with CDCE925PWR and CDCE949PWR, the CDCEL925PWR provides optimal integration for cost-sensitive 1.8V consumer electronics - delivering five precision clocks in the smallest footprint and lowest power envelope of the CDCEx9xx family.

Availability

CDCEL925PWR is available at Aetrix Electronics and suitable for digital television, set-top box, and DVD recorder applications requiring stable component supply, long-term lifecycle support, and consistent electrical performance across temperature.

Supply support for CDCEL925PWR 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

Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and clock solutions for industrial, automotive, and consumer markets.

The CDCE(L)9xx product line was designed to deliver flexible, low-cost, and low-jitter clock synthesis for multimedia and connectivity applications - emphasizing in-system programmability, EMI reduction, and seamless integration with TI's DaVinci™ and OMAP™ processors.

FAQ

What is the maximum output frequency supported by the CDCEL925PWR?

The CDCEL925PWR supports a maximum LVCMOS output frequency of 230MHz. This capability is verified under recommended operating conditions (VDDOUT = 1.8V, TA = –40°C to 85°C) and applies to all five outputs (Y1–Y5). The device achieves this using its dual-PLL architecture with deep M/N dividers, enabling precise generation of high-speed clocks for USB 2.0, Ethernet PHY, and video interfaces without external frequency multipliers. The CDCEL925PWR maintains <130ps cycle-to-cycle jitter even at 230MHz.

Does the CDCEL925PWR require external loop filter components?

No, the CDCEL925PWR does not require external loop filter components. Its PLLs integrate all necessary loop filter elements internally, and the device automatically adjusts these components based on the configured VCO frequency and divider settings. This eliminates external passive components, reduces PCB area, and simplifies design validation. The integrated filter ensures optimized jitter transfer characteristics and stable lock across the full 80–230MHz VCO range, as confirmed in the CDCEL925PWR datasheet Section 5.5.

Can the CDCEL925PWR generate zero-ppm clocks for audio and video applications?

Yes, the CDCEL925PWR can generate zero-ppm clocks for audio and video applications. Using its deep M/N divider architecture and a stable 27MHz crystal reference, it produces exact integer-ratio frequencies such as 48MHz (audio), 74.25MHz (HD video), and 148.5MHz (dual-link video) with no accumulated timing error. This capability is explicitly documented in the CDCEL925PWR datasheet Section 3 and validated in typical application schematics for TI DaVinci™ and OMAP™ platforms.

How is the CDCEL925PWR programmed in-system?

The CDCEL925PWR is programmed in-system via its 2-wire I²C-compatible serial interface (SDA/SCL pins), supporting standard-mode (100kHz) and fast-mode (400kHz) operation. All registers - including PLL configuration, output dividers, SSC parameters, and control pin mapping - are accessible through this interface. Factory-default settings are stored in nonvolatile EEPROM and can be overwritten in-circuit without removing the CDCEL925PWR from the PCB. Programming is performed using TI's Pro-Clock™ software or custom I²C host firmware.

What is the purpose of the VCtrl pin on the CDCEL925PWR?

The VCtrl pin on the CDCEL925PWR serves as the analog control voltage input for the on-chip VCXO (voltage-controlled crystal oscillator) function. Applying a DC voltage between 0V and 1.8V to VCtrl enables fine frequency pulling of the crystal-based input clock by up to ±150ppm, allowing synchronization to external timing references like PWM signals. When not used, VCtrl must be left open or pulled up to VDD; improper termination causes undefined frequency behavior. This feature is detailed in CDCEL925PWR datasheet Sections 4 and 5.3.