What is the AD9508BCPZ-REEL7?
The AD9508BCPZ-REEL7 is a 1:4 fanout buffer and clock divider from Analog Devices, accepting a single CMOS input and distributing it to four outputs configurable as CMOS, HSTL, or LVDS. It operates up to 1.65 GHz, making it suitable for distributing high-speed reference clocks to multiple ADCs, DACs, or FPGAs in a clock tree.
The 1.65 GHz maximum frequency sets the upper bound for the input clock rate. For a 1 GHz reference clock, the part has 650 MHz of margin, but at 1.6 GHz the jitter performance will be closer to the datasheet limits. The 1:4 fanout ratio means one input drives four loads directly, saving external fanout buffers and reducing PCB area. The differential input/output capability allows the part to handle LVDS or HSTL signals natively, which is essential for low-jitter distribution in high-speed converter systems. Supply voltage spans 2.375 V to 3.465 V, covering common 2.5 V and 3.3 V rails. The wide range gives flexibility in mixed-voltage systems, but the output swing will track the supply — a 2.5 V rail produces a smaller CMOS swing than 3.3 V, which may affect noise margin at the receiver.
Production status and sourcing posture
It is available for new designs and volume production through standard distribution.
Package and mounting notes
The part is housed in a 24-lead LFCSP (4x4 mm) with an exposed pad. The 0.50 mm pitch demands careful solder paste stencil design and a controlled reflow profile. The exposed pad also serves as the ground return for the die, so a solid via array to the ground plane is recommended.