1 Features

1• 2:8 Differential Buffer

• Low Additive Jitter: < 300-fs RMS in 10-kHz to

20-MHz

• Low Output Skew of 45 ps (Maximum)

• Universal Inputs Accept LVDS, LVPECL, and

LVCMOS

• Selectable Clock Inputs Through Control Pin

• 8 LVDS Outputs, ANSI EIA/TIA-644A Standard

Compatible

• Clock Frequency: Up to 800 MHz

• Device Power Supply: 2.375 V to 2.625 V

• LVDS Reference Voltage, VAC_REF, Available for

Capacitive Coupled Inputs

• Industrial Temperature Range: –40°C to 85°C

• Packaged in 5-mm × 5-mm, 28-Pin VQFN (RHD)

• ESD Protection Exceeds 3-kV HBM, 1-kV CDM

2 Applications

• Telecommunications and Networking

• Medical Imaging

• Test and Measurement Equipment

• Wireless Communications

• General-Purpose Clocking

3 Description

The CDCLVD1208 clock buffer distributes one of two

selectable clock inputs (IN0 and IN1) to 8 pairs of

differential LVDS clock outputs (OUT0 through OUT7)

with minimum skew for clock distribution. The

CDCLVD1208 can accept two clock sources into an

input multiplexer. The inputs can either be LVDS,

LVPECL, or LVCMOS.

The CDCLVD1208 is specifically designed for driving

50-Ω transmission lines. In case of driving the inputs

in single-ended mode, the appropriate bias voltage,

VAC_REF, must be applied to the unused negative

input pin.

The IN_SEL pin selects the input which is routed to

the outputs. If this pin is left open, it disables the

outputs (static). The part supports a fail-safe function.

The device incorporates an input hysteresis which

prevents random oscillation of the outputs in the

absence of an input signal.

The device operates in 2.5-V supply environment and

is characterized from –40°C to 85°C (ambient

temperature). The CDCLVD1208 is packaged in

small, 28-pin, 5-mm × 5-mm VQFN package.