Texas Instruments CDCE949PW

Overview

CDCE949PW from Texas Instruments is a programmable 4-PLL LVCMOS clock generator with 9 configurable outputs, 2.5V–3.3V output supply, ±150ppm VCXO pull range, and 60ps typical cycle-to-cycle jitter. It generates precise clocks up to 230MHz for video/audio timing, USB, Ethernet, and wireless interfaces in consumer electronics.

For engineers reviewing the CDCE949PW datasheet, CDCE949PW pinout, CDCE949PW application, or CDCE949PW equivalent, this page delivers verified specifications, TSSOP-24 pin mapping, real-world use cases in STBs and DVD recorders, and two validated alternative clock synthesizers with documented functional differences.

Technical Context

The CDCE949PW integrates four independent PLLs with auto-adjusted internal loop filters, enabling stable low-jitter synthesis across varying VCO frequencies (80–230MHz) and divider configurations. Each PLL supports center-spread or down-spread SSC modulation for EMI reduction.

It accepts either an 8–32MHz crystal (with programmable 0–20pF load capacitance) or single-ended LVCMOS input up to 160MHz, and delivers nine LVCMOS outputs with separate VDDOUT pins (2.5V/3.3V), 3-state control, and user-defined S0/S1/S2 function mapping via EEPROM.

Key Specifications

Pinout & Package

Packaged in 24-pin TSSOP (PW), 7.8mm × 6.4mm footprint, with 1.8V core supply (VDD) and dual-output supply rails (VDDOUT at 2.5V or 3.3V).

Key Features

Applications

Equivalent & Alternatives

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

Compared with CDCE937PW and Si5338A-D-GM, the CDCE949PW uniquely balances 9-output density, per-PLL SSC control, and VCXO synchronization in a cost-optimized TSSOP package-making it optimal for multi-interface consumer devices where EMI compliance and design simplicity are prioritized over sub-picosecond jitter.

Availability

CDCE949PW is available at Aetrix Electronics and suitable for digital television, set-top box, and optical disc recorder applications requiring stable component supply, long-term lifecycle support, and consistent parametric performance across production batches.

Supply support for CDCE949PW 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, with decades of expertise in high-performance timing devices for consumer and industrial markets.

The CDCE(L)9xx family was designed specifically for cost-sensitive, multi-clock consumer electronics-delivering flexible PLL-based synthesis with integrated EEPROM, SSC, and mixed-voltage outputs in compact packages.

FAQ

What is the maximum output frequency supported by the CDCE949PW?

The CDCE949PW supports LVCMOS output frequencies up to 230MHz, as confirmed in the Electrical Characteristics table (Section 5.5) under parameter fOUT. This applies to all nine Y1–Y9 outputs when configured with appropriate PLL and divider settings, and is validated across the full –40°C to +85°C operating temperature range.

Does the CDCE949PW require external loop filter components?

No, the CDCE949PW integrates all necessary loop filter components internally. As stated in the Features section and Section 7.1, "PLL loop filter components [are] integrated," and Section 5.5 confirms automatic adjustment based on PLL frequency and divider settings-eliminating external resistors/capacitors and reducing PCB area.

Can the CDCE949PW generate zero-ppm clocks for audio/video applications?

Yes, the CDCE949PW supports 0ppm clock generation using its deep M/N divider ratio, explicitly cited in the Description and Feature sections. This capability enables exact derivation of standards-compliant frequencies (e.g., 27MHz, 74.25MHz, 48MHz) from common reference crystals like 27MHz-critical for HDMI, USB Audio, and broadcast video timing.

What are the valid supply voltage ranges for VDD and VDDOUT on the CDCE949PW?

The CDCE949PW requires VDD = 1.7–1.9V (nominal 1.8V) for the core logic and PLLs, and VDDOUT = 2.3–3.6V (supporting both 2.5V and 3.3V systems) for the nine LVCMOS outputs. These values are specified in Section 5.3 (Recommended Operating Conditions) and distinguish CDCE949PW from the 1.8V-only CDCEL949 variant.

How is spread-spectrum clocking (SSC) implemented on the CDCE949PW?

The CDCE949PW implements SSC independently per PLL, supporting both center-spread and down-spread modes with programmable spread amounts from 0% to ±2%. Configuration is done via EEPROM registers, and SSC modulation is applied directly to the VCO control voltage-enabling EMI reduction without altering output frequency accuracy or requiring external circuitry.