CY28351

CY28351 Differential Clock Buffer/Driver DDR400- and DDR333-Compliant Features Supports 333-MHz and 400-MHz DDR SDRAM 60- – 200-MHz operating frequency Phase-locked loop (PLL) clock distribution for double data rate synchronous DRAM applications Distributes one clock input to ten differential outputs External feedback pin (FBIN) is used to synchronize the outputs to the clock input Conforms to the DDRI specification Spread Aware for electromagnetic interference (EMI) reduction 48-pin SSOP package Description This PLL clock buffer is designed for 2.5-VDD and 2.5-AVDD operation and differential outputs levels. This device is a zero delay buffer that distributes a clock input (CLKIN) to ten differential pairs of clock outputs (YT[0:9], YC[0:9]) and one feedback clock output (FBOUT). The clock outputs are individually controlled by the serial inputs SCLK and SDATA. The two-line serial bus can set each output clock pair (YT[0:9], YC[0:9]) to the Hi-Z state. When AVDD is grounded, the PLL is turned off and bypassed for the test purposes. The PLL in this device uses the input clock (CLKIN) and the feedback clock (FBIN) to provide high-performance, low-skew, low-jitter output differential clocks. Block Diagram 10 Pin Configuration YT0 YC0 YT1 YC1 YT2 YC2 SCLK SDATA YT4 YC4 YT5 YC5 YT6 YC6 CLKIN PLL FBIN YT7 YC7 YT8 YC8 YT9 YC9 CY28351 Serial Interface Logic YT3 YC3 AVDD FBOUT VSS YC0 YT0 VDDQ YT1 YC1 VSS VSS YC2 YT2 VDD SCLK CLKIN NC VDDI AVDD AVSS VSS YC...