Infineon Technologies CY2548QC003T

Overview

CY2548QC003T from Cypress Semiconductor is a quad-PLL programmable clock generator with spread spectrum capability, designed for high-precision timing synthesis in multi-clock domain systems. It delivers nine programmable LVCMOS outputs (3–166 MHz), supports 2.5 V/3.0 V/3.3 V reference input (CLKIN), features fractional-N PLLs for zero-PPM error synthesis, and integrates two spread-spectrum PLLs (PLL3/PLL4) for EMI reduction in PC and networking applications.

For engineers reviewing the CY2548QC003T datasheet, CY2548QC003T pinout, CY2548QC003T application, or CY2548QC003T equivalent, key selection criteria include its 24-pin QFN package, bank-specific output voltage control (VDD_CLK_B1/B2/B3), glitch-free frequency switching via FS0–FS2, and nonvolatile one-time programmability for custom PLL configurations and drive strength settings.

Technical Context

The CY2548QC003T implements four independent fractional-N PLLs-two with integrated spread spectrum (PLL3/PLL4) using Lexmark or Linear modulation profiles-and accepts a 2.5 V/3.0 V/3.3 V reference clock on CLKIN (8–166 MHz). It lacks crystal oscillator circuitry (XIN/XOUT unused), distinguishing it from CY2544.

Output clocks are grouped into three voltage-programmable banks (Bank1: CLK1–CLK3; Bank2: CLK4–CLK6; Bank3: CLK7–CLK9), each powered by dedicated VDD_CLK_Bx supplies (1.8 V/2.5 V/3.0 V/3.3 V). The crossbar switch enables arbitrary routing of six internal clock sources (CLKIN, EXCLKIN, PLL1–PLL4) to any output, supporting unrelated frequency synthesis across domains.

Key Specifications

Pinout & Package

24-pin QFN (4 mm × 4 mm, 0.5 mm pitch), exposed thermal pad, RoHS-compliant. Pin functions validated per Cypress Document 001-12563 Rev. *M (CY2548-specific pinout).

Key Features

Applications

Equivalent & Alternatives

CY2548QC003T has two verified functional alternatives with documented differences in voltage support, crystal interface, and spread spectrum implementation.

Compared with Si5338A-D-GM and ICS8430I-01, CY2548QC003T uniquely combines OTP-based fractional-N synthesis, dual hardware SSC control, and three independent output voltage banks-enabling single-chip EMI-compliant clocking for complex, mixed-voltage embedded systems without external configuration or modulation circuitry.

Availability

CY2548QC003T is available at Aetrix Electronics and suitable for PC motherboard design, industrial PLC backplane synchronization, and consumer set-top box SoC interface applications requiring stable component supply, long-term lifecycle assurance, and traceable sourcing.

Supply support for CY2548QC003T 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

Cypress Semiconductor (now part of Infineon Technologies) is a fabless semiconductor company specializing in high-performance timing, memory, and programmable logic solutions for industrial, automotive, and computing markets.

CY2548 belongs to Cypress's programmable clock generator product line, engineered specifically for EMI-sensitive, multi-domain systems requiring flexible, nonvolatile, and glitch-free clock synthesis without external configuration hardware.

FAQ

Does CY2548QC003T support crystal oscillator input?

No. Unlike CY2544, CY2548QC003T does not support crystal input on XIN/XOUT. Pin 23 is marked DNU (Do Not Use), and XIN/EXCLKIN functions solely as an external 2.5 V/3.0 V/3.3 V clock input (EXCLKIN). The device requires a clean, buffered reference signal on CLKIN or EXCLKIN to achieve PLL lock.

How is spread spectrum enabled or disabled on CY2548QC003T?

Spread spectrum is controlled via the CLK7/SSON pin (Pin 15). When configured as an input, driving SSON low disables spread spectrum on PLL3 and PLL4; driving it high enables modulation. The specific profile (Lexmark/Linear) and spread range (±0.125% to ±2.5% center, or –0.25% to –5.0% down) are programmed into OTP memory during customization.

Can all nine outputs operate at different voltages simultaneously?

Yes. Each of the three output banks (Bank1: CLK1–CLK3; Bank2: CLK4–CLK6; Bank3: CLK7–CLK9) is powered by its own VDD_CLK_Bx supply (Pins 3, 14, 16), which can be independently set to 1.8 V, 2.5 V, 3.0 V, or 3.3 V. This allows concurrent generation of 1.8 V DDR clock, 2.5 V PCIe REFCLK, and 3.3 V legacy peripheral clocks from a single device.

What happens during frequency switching using FS0–FS2 pins?

When FS0–FS2 (Pins 8, 9, 10) change state, the device selects one of eight preprogrammed PLL configurations. Outputs switch glitch-free because reconfiguration occurs only through output dividers-not VCO or feedback dividers-ensuring phase continuity and eliminating runt pulses or metastability in downstream logic.