SY58035UMG-TR

Clock Buffers, Drivers Overview

The SY58035UMG-TR is a high-speed, precision fanout buffer featuring a 2:1 multiplexer input for clock switchover applications. It provides six ultra-low skew LVPECL copies of the selected differential input, supporting clock frequencies from DC to over 4.5GHz. The device operates on a 2.5V ±5% or 3.3V ±10% supply with a maximum power supply current of 250mA. Key electrical parameters include a propagation delay of less than 320ps, rise/fall times under 110ps, and output-to-output skew below 20ps. It utilizes a unique 3-pin input termination architecture compatible with CML, PECL, and LVDS signals in both AC- and DC-coupled configurations.

Clock Buffers, Drivers Feature Summary

• Integrated 2:1 MUX input enables redundant clock switchover functionality via a single-ended TTL/CMOS SEL pin.
• Ultra-low jitter design achieves a typical RMS phase jitter of 50fs (12kHz to 20MHz integration range).
• Unique 3-pin input termination allows direct interfacing with differential signals as small as 100mV without external level shifting.
• Six temperature-compensated LVPECL outputs provide an 800mV differential swing with low EMI characteristics.

Clock Buffers, Drivers Applications

• Redundant clock distribution systems
• SONET/SDH clock and data distribution networks
• Fibre Channel signal distribution
• Gigabit Ethernet clock distribution

Clock Buffers, Drivers Procurement Notes

Verify that the ordering suffix 'TR' corresponds to the Tape and Reel packaging format specified in the datasheet. Confirm the package type is MLF-32 and check RoHS compliance status, noting that the 'G' suffix indicates a Pb-Free variant with NiPdAu finish. Ensure moisture sensitivity handling protocols are followed as the component is humidity sensitive.

Clock Buffers, Drivers Selection Notes

Select this component when a 1:6 fanout buffer with integrated clock switchover is required for frequencies up to 4.5GHz. Choose this part over the SY58034U if LVPECL outputs are preferred over CML, or over the SY58036U if an 800mV swing is needed instead of 400mV. Ensure the application supports the 2.5V or 3.3V supply voltage ranges and requires the specific MLF-32 footprint.

Clock Buffers, Drivers Part Context

The SY58035UMG-TR belongs to Micrel’s Precision Edge product line, which focuses on high-speed, low-jitter timing solutions. It was originally manufactured by Micrel, Inc., prior to its acquisition by Microchip Technology. The device is designed to replace legacy buffering solutions requiring complex external termination networks for differential inputs.

Clock Buffers, Drivers Replacement Considerations

Public confirmed substitute part numbers: SY58035UMI, SY58035UMITR.

Clock Buffers, Drivers FAQ

How does the device handle differential input termination?

The SY58035U features a unique 3-pin input termination architecture where each side of the differential pair internally terminates to a VT pin through 50Ω resistors, eliminating the need for external termination resistor networks in the signal path.

What is the function of the VREF-AC pins?

The VREF-AC pins bias to VCC–1.2V and are used specifically for AC-coupling inputs. They should be connected directly to their respective VT pins and bypassed with a 0.01µF capacitor to VCC.

Can unused LVPECL output pairs be left floating?

Yes, unused differential output pairs may be left floating. However, single-ended outputs must be terminated or balanced to maintain signal integrity.