Renesas 151TS311TE-E

Overview

151TS311TE-E from Renesas Electronics is a spread spectrum clock generator IC designed for DDR SDRAM memory systems, delivering seven differential 2.5 V clock outputs (DDRT/DDRC[6:0]) at 133 MHz or 167 MHz, with integrated SSC modulation (–0.5%, –1.0%, or OFF), 14.318 MHz reference output, and CPUCLK at 2.5 V - used in laser beam printers and other EMI-sensitive embedded systems.

For engineers reviewing the 151TS311TE-E datasheet, 151TS311TE-E pinout, 151TS311TE-E application, or 151TS311TE-E equivalent, key selection criteria include DDR clock skew control (±480 ps), SSC modulation depth selection, differential output drive strength (16.2 mA), and TSSOP-48 package compatibility with high-density PCB layouts.

Technical Context

The 151TS311TE-E integrates a crystal oscillator input (X1/X2), PLL-based frequency synthesis, and an SSC modulator to reduce EMI by spreading spectral energy across ±0.5% or ±1.0% of nominal frequency. It supports two selectable DDR clock frequencies via FS0 and provides independent skew and slew rate control for CPUCLK and all seven DDR clock pairs.

It features three dedicated skew control groups: TCPURAM[2:0] for CPUCLK-to-DDRT0/DDRC0 alignment, TRAMRAM[2:0] for inter-DDR-group skew, and separate SRCPU[1:0] and SRRAM[1:0] inputs for fine-tuning edge rates on CPUCLK and DDR outputs respectively - all implemented with internal 120 kΩ pulldown resistors.

Key Specifications

Pinout & Package

TSSOP-48 (PTSP0048KA-A / TTP-48DBV) package with 0.5 mm pitch, 6.1 mm × 12.5 mm body, Ni/Pd/Au plating, and 0.2 g typical mass - optimized for automated SMT assembly and thermal dissipation in compact printer logic boards.

Key Features

Applications

Equivalent & Alternatives

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

Compared with IDT72V2231L and ICS9FGP102, the 151TS311TE-E uniquely balances DDR2-specific timing precision, integrated EMI suppression, and TSSOP-48 compactness - making it optimal for cost-sensitive, space-constrained LBP and industrial controller designs where SSC is mandatory.

Availability

151TS311TE-E is available at Aetrix Electronics and suitable for laser beam printers, industrial HMIs, and networked embedded controllers requiring stable component supply, EMI-compliant clock generation, and DDR2 memory interface timing accuracy.

Supply support for 151TS311TE-E 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

Renesas Electronics is a global semiconductor leader specializing in microcontrollers, analog, power, and timing solutions for automotive, industrial, and consumer applications.

The 151TS311TE-E belongs to Renesas' legacy spread spectrum clock generator product line, engineered specifically for EMI mitigation in DDR-based office equipment and industrial control systems operating under strict regulatory emission limits.

FAQ

What is the primary function of the 151TS311TE-E in DDR memory systems?

The 151TS311TE-E serves as a dedicated spread spectrum clock generator that produces seven differential DDR clock pairs (DDRT/DDRC[6:0]), one CPU clock (CPUCLK), and a 14.318 MHz reference output - all synchronized to reduce EMI while maintaining precise timing alignment required by DDR SDRAM interfaces. Its design directly targets EMI compliance in laser beam printers and similar embedded systems.

Does the 151TS311TE-E support both 133 MHz and 167 MHz DDR clock frequencies?

Yes, the 151TS311TE-E supports both 133 MHz and 167 MHz DDR clock outputs, selected via the FS0 input pin. The device maintains specified jitter (±180 ps cycle-to-cycle) and skew (120–480 ps) across both frequencies under all SSC modulation modes (OFF, –0.5%, –1.0%), as confirmed in the AC electrical characteristics tables of its official datasheet.

How does the 151TS311TE-E implement spread spectrum clocking, and what are the available modulation depths?

The 151TS311TE-E implements spread spectrum clocking using an internal modulator that dithers output frequencies at ≤30 kHz. Modulation depth is selected via SSON# and SS% pins: –0.5% (SSON# = L, SS% = L), –1.0% (SSON# = L, SS% = H), or OFF (SSON# = H). These settings are explicitly defined in Table 2 of the HD151TS311 datasheet Rev. 2.00.

What package type and pin count does the 151TS311TE-E use?

The 151TS311TE-E uses a TSSOP-48 package (JEITA code TTP-48DBV, Renesas code PTSP0048KA-A), with 0.5 mm pitch, 6.1 mm × 12.5 mm body dimensions, and Ni/Pd/Au terminal plating. This information is confirmed in the "Ordering Information" section and mechanical drawing on page 14 of the HD151TS311 datasheet Rev. 2.00.

Can the 151TS311TE-E's output skew and slew rate be configured, and how?

Yes, the 151TS311TE-E provides configurable skew and slew rate: TCPURAM[2:0] and TRAMRAM[2:0] pins adjust CPUCLK-to-DDRT0 and inter-DDR-group skew in discrete steps; SRCPU[1:0] and SRRAM[1:0] pins set CPUCLK and DDR output edge rates. All control inputs feature internal 120 kΩ pulldowns, enabling default operation without external biasing - as detailed in Tables 4–7 and the Terminal Description section.