Renesas 8402015AKILF

Overview

8402015AKILF from Renesas Electronics (formerly IDT) is a low-phase-noise crystal-to-LVDS/LVCMOS clock synthesizer with integrated PLL/VCO, generating three independent output banks (25/50/125 MHz) and a 25 MHz reference from a single 25 MHz parallel-resonant crystal. It delivers 0.373 ps RMS phase jitter at 125 MHz LVDS output and operates fully at 3.3 V across –40°C to +85°C for high-reliability timing in FPGA, ASIC, and telecom infrastructure.

For engineers reviewing the 8402015AKILF datasheet, 8402015AKILF pinout, 8402015AKILF application, or 8402015AKILF equivalent, key selection criteria include bank-selectable output frequencies (25/50/125 MHz), differential LVDS vs. single-ended LVCMOS output routing, RMS phase jitter performance under defined integration bands, supply isolation requirements per VDD/VDDA/VDDO rail, and VFQFN thermal pad layout compliance.

Technical Context

The 8402015AKILF implements a 500 MHz VCO with integer-N PLL architecture, using ÷4, ÷10, and ÷20 dividers to derive Bank A (25/50 MHz), Bank B (125 MHz), and Bank C (125 MHz LVDS) outputs. Crystal input drives an internal oscillator with 25 MHz fundamental-mode operation and 18 pF load capacitance requirement.

Output enable logic (OE[2:0]) configures bank activation and frequency mode per Table 3 - e.g., OE2=1/OE1=1/OE0=0 enables 50 MHz on Bank A while disabling Bank B/C. Master reset (MR) forces all LVCMOS outputs LOW and LVDS pairs into complementary HIGH/LOW states, ensuring deterministic startup behavior.

Key Specifications

Pinout & Package

8402015AKILF is housed in a lead-free, RoHS-compliant 32-pin VFQFN (K package) with 5 mm × 5 mm footprint and 0.5 mm pitch. The exposed thermal pad must be soldered to a PCB ground plane via ≥6 thermal vias (12–13 mil diameter, 1 oz plating) to maintain junction temperature ≤99.5°C at 85°C ambient and full output load.

Key Features

Applications

Equivalent & Alternatives

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

Compared with Si5338A-A-GM and ICS8430I-01LFT, the 8402015AKILF uniquely combines crystal-based simplicity, triple-bank configurability, and industry-leading 0.373 ps jitter - making it optimal for fixed-frequency, low-noise, space-constrained applications where programmability is unnecessary.

Availability

8402015AKILF is available at Aetrix Electronics and suitable for FPGA clock distribution, telecom line card timing, ASIC test equipment, industrial PLC control, and high-speed data acquisition systems requiring stable component supply with guaranteed long-term availability.

Supply support for 8402015AKILF 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 Corporation is a global semiconductor leader formed from the merger of Renesas Technology and NEC Electronics, specializing in microcontrollers, analog, power, and timing solutions.

The 8402015AKILF belongs to Renesas' FemtoClock™ family of ultra-low-jitter clock synthesizers, designed specifically for high-speed serial interface timing in communications, computing, and industrial systems where phase noise directly impacts bit error rate.

FAQ

What crystal specifications are required for reliable operation of the 8402015AKILF?

The 8402015AKILF requires a 25 MHz fundamental-mode, parallel-resonant crystal with 18 pF load capacitance, ≤50 Ω ESR, and 7 pF shunt capacitance. External 27 pF load capacitors (C1/C2) are mandatory for ppm-accurate frequency lock. Crystals rated for 50 MHz or other frequencies are incompatible - the device is characterized exclusively for 25 MHz crystal input.

Can the 8402015AKILF generate 50 MHz outputs on Bank B or Bank C?

No. Bank B (QB0–QB2) and Bank C (QC0/nQC0–QC2/nQC2) are fixed at 125 MHz output frequency per the internal divider architecture (÷4 from 500 MHz VCO). Only Bank A (QA0–QA2) supports 50 MHz operation, enabled when OE2=1 and OE0=0 per Table 3. Bank B and Bank C cannot be reconfigured to 50 MHz.

How should unused LVDS outputs be terminated on the 8402015AKILF?

Unused LVDS outputs (e.g., QC1/nQC1 when only QC0/nQC0 is needed) must be terminated with a 100 Ω resistor across the differential pair, placed as close as possible to the 8402015AKILF output pins. Leaving them unterminated causes signal reflections, increased EMI, and potential jitter degradation - this is explicitly required in the "Recommendations for Unused Input and Output Pins" section of the datasheet.

Does the 8402015AKILF support LVCMOS input on XTAL_IN?

Yes - XTAL_IN accepts a single-ended LVCMOS clock signal via AC coupling (0.1 µF capacitor), but amplitude must be reduced to half-swing (1.65 V ±5%) to avoid rail interference and noise coupling. Full-swing LVCMOS is not supported. XTAL_OUT must remain floating in this configuration, and the driver's output impedance plus series resistance must match the transmission line impedance (typically 50 Ω).

What is the maximum allowable junction temperature for continuous operation of the 8402015AKILF?

The maximum recommended junction temperature for the 8402015AKILF is 125°C. Under worst-case conditions (3.465 V supplies, all 9 outputs loaded, 85°C ambient, no airflow), calculated junction temperature is 99.5°C - well within limit. Maintaining θJA ≤37°C/W via proper thermal pad layout and ≥6 ground vias is essential to sustain this margin.