NXP Semiconductors MC88LV915TFN

Overview

The MC88LV915TFN from Motorola is a low-skew CMOS PLL clock driver designed for synchronous clock distribution in high-performance PC and workstation systems. It locks five Q outputs (Q0–Q4) to a reference clock with <500 ps output-to-output skew, provides 2X_Q (up to 100 MHz) and Q/2 outputs, and supports frequency ratios of 2:1, 1:1, and 1:2 via FREQ_SEL pin control.

For engineers reviewing the MC88LV915TFN datasheet, MC88LV915TFN pinout, MC88LV915TFN application, or MC88LV915TFN equivalent, key selection criteria include guaranteed 500 ps rising-edge skew across Q0–Q4, ±36 mA CMOS/TTL-compatible drive strength, 3.3 V operation, PLCC-28 package compatibility, and PLL-based 2× multiplication capability for system timing synchronization.

Technical Context

The MC88LV915TFN implements a phase-locked loop with internal VCO optimized for 20–100 MHz operation, enabling precise alignment of rising edges between SYNC and FEEDBACK inputs (part-to-part skew <550 ps). Its feedback path includes programmable divide-by-1/divide-by-2 selection via FREQ_SEL, allowing VCO frequency tuning while maintaining optimal lock range.

It delivers seven synchronized outputs: five non-inverted Q outputs (Q0–Q4), one inverted Q5 (180° phase shift), one 2X_Q output at double Q frequency (max 100 MHz), and one Q/2 output at half Q frequency. All outputs support 3-state enable/disable via OE/RST and feature LOCK indicator signaling steady-state phase lock within ≤10 ms.

Key Specifications

Pinout & Package

MC88LV915TFN is housed in a 28-lead plastic PLCC (FN suffix, Case 776–02), surface-mount package with gull-wing leads and exposed thermal pad.

Key Features

Applications

Equivalent & Alternatives

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

Compared with ICS8302AMLF and PI6C20400LEX, the MC88LV915TFN uniquely combines 100 MHz 2X_Q capability, five low-skew Q outputs, Q/2 and Q5 outputs, FREQ_SEL programmability, and dedicated test-mode pins - making it optimal for complex, test-aware PC/workstation clock architectures requiring flexibility and precision.

Availability

MC88LV915TFN is available at Aetrix Electronics and suitable for PC mainboard design, workstation multi-processor synchronization, and embedded graphics subsystem timing requiring stable component supply and long-term industrial availability.

Supply support for MC88LV915TFN 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

Motorola (now part of NXP Semiconductors) is a pioneer in high-performance timing solutions, known for robust analog-intensive ICs serving computing and communications markets.

The MC88LV915TFN belongs to Motorola's low-skew PLL clock driver family, engineered specifically for synchronous clock distribution in high-speed PC and workstation platforms where deterministic skew and flexible frequency synthesis are critical.

FAQ

What is the maximum guaranteed operating frequency of the 2X_Q output on the MC88LV915TFN?

The MC88LV915TFN guarantees a maximum 2X_Q output frequency of 100 MHz under recommended operating conditions (TA = 0°C to +70°C, VCC = 3.3 V ±0.3 V). This specification is validated with the device in phase-locked condition and applies to all production units meeting Motorola's AC characteristics table. The MC88LV915TFN achieves this using its internal VCO optimized for 20–100 MHz operation.

How does the FREQ_SEL pin affect the MC88LV915TFN's PLL behavior?

The FREQ_SEL pin selects the feedback divider ratio in the MC88LV915TFN's PLL: high = divide-by-1, low = divide-by-2. When FREQ_SEL is low, the VCO runs at twice the selected output frequency, allowing the MC88LV915TFN to maintain optimal VCO operation (>20 MHz) even with low-frequency reference clocks (e.g., 5–25 MHz). This preserves loop stability and jitter performance without changing external components.

Can the MC88LV915TFN be used for board-level functional testing, and how?

Yes, the MC88LV915TFN supports board-level functional testing via two dedicated pins: pulling PLL_EN low disables the VCO and routes the SYNC input directly to outputs, enabling low-frequency validation; pulling OE/RST low places all clock outputs (2X_Q, Q0–Q4, Q5, Q/2) into high-impedance state for isolation during boundary-scan or probe-based testing. The LOCK output remains active to confirm PLL status independently.

What is the guaranteed output-to-output skew specification for Q0–Q4 on the MC88LV915TFN?

The MC88LV915TFN guarantees output-to-output skew of less than 500 ps between the rising edges of Q0–Q4 outputs, measured under AC conditions (TA = 0°C to +70°C, VCC = 3.3 V ±0.3 V, 50 Ω load terminated to VCC/2). This skew value reflects worst-case variation across process, voltage, and temperature, and is critical for maintaining timing margins in high-speed synchronous systems using the MC88LV915TFN.

Does the MC88LV915TFN support both CMOS and TTL logic families on its inputs and outputs?

Yes, the MC88LV915TFN supports TTL-level inputs (VIH ≥ 2.0 V, VIL ≤ 0.8 V) and delivers CMOS-level outputs (VOH ≥ 2.4 V at –24 mA, VOL ≤ 0.44 V at +24 mA) compatible with both CMOS and TTL loads. Its ±36 mA drive strength and ±88 mA IOL/IOH ratings ensure reliable switching into 50 Ω transmission lines, making the MC88LV915TFN interoperable across mixed-logic designs without level-shifting circuitry.