MAX3679A
MAX3679A is Low-Jitter Crystal to LVPECL Clock Generator manufactured by Maxim Integrated.
19-4858; Rev 0; 8/09
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KIT ATION EVALU E L B AVAILA
+3.3V, Low-Jitter Crystal to LVPECL Clock Generator
General Description Features
- Crystal Oscillator Interface: 25MHz
- CMOS Input: 25MHz
- Output Frequencies for Ethernet 62.5MHz, 125MHz, 156.25MHz, 312.5MHz
- Low Jitter 0.14ps RMS (1.875MHz to 20MHz) 0.36ps RMS (12k Hz to 20MHz)
- Excellent Power-Supply Noise Rejection
- No External Loop Filter Capacitor Required
The MAX3679A is a low-jitter precision clock generator with the integration of three LVPECL and one LVCMOS outputs optimized for Ethernet applications. The device integrates a crystal oscillator and a phase-locked loop (PLL) clock multiplier to generate high-frequency clock outputs for Ethernet applications. Maxim’s proprietary PLL design Features ultra-low jitter (0.36ps RMS) and excellent power-supply noise rejection, minimizing design risk for network equipment.
Applications
Ethernet Networking Equipment
Ordering Information
PART MAX3679AETJ+ TEMP RANGE -40°C to +85°C PIN-PACKAGE 32 TQFN-EP-
Pin Configuration appears at end of data sheet.
+Denotes a lead(Pb)-free/Ro HS-pliant package.
- EP = Exposed pad.
Typical Application Circuit
+3.3V ±5% 10.5Ω 0.1μF 0.1μF 0.1μF 0.01μF 0.1μF
10μF 0.1μF MR
VCC VCCA REF_IN IN_SEL QAC_OE QA_OE QB0_OE VCC QB1_OE BYPASS SELA1 SELA0 SELB1 SELB0 RES1 RES0 X_OUT
VCCO_A
VCCO_B
VDDO_A QA_C 125MHz QA QA 125MHz
36Ω
Z0 = 50Ω
ASIC
Z0 = 50Ω Z0 = 50Ω 50Ω...