RTM680-229

DDR/SDRAM Buffer General Description The RTM 680-229 is a 3.3V/2.5V DDR / SDRAM fan out buffer. The RTM680-229 can be used in conjunction with the RTM560/660/360 or similar clock synthesizer for the VIA 266/333/400 chipset. The clock chip provides standard serial bus for programming device function. And RTM 680-229 also builds in the enhance function. Features z z z z z z z z z Support Up to 400MHz DDR. Programmable clock skew. Programmable drive strength. Power Down feature. 1 input to 12 output buffer 1 feedback clock Supports 2 DDR DIMMs. Supports 3 SDRAM DIMMs. Supports 2 type package ID (D2/D6) by bonding option. Delay select DDR#/SDRAM PAD CLK OUT DDR#/SDRAM clk_in Delay select DDR PAD CLK OUT PD# Delay select FEED BACK PAD CLK OUT RESET# Power On Reset# RESET# SCLK I2C SDATA CR06h CR07h CR08h CR10h CR23h CR24h STOP# 02/09/12 -1- DDR/SDRAM Buffer Pin Description Pin Name SEL_DDR/SDR# 228 R 28 Type I Description DDR mode Select: Select input for DDR or SDRAM mode 0=SDRAM mode. 1=DDR mode. Data pin for serial interface. Clock pin for serial interface. Buffer Input: Single ended buffer input. 2.5V inout for DDR mode;3.3V for SDRAM mode. Feedback output: Output voltage depend on VDD3.3_2.5V. Power Down Control: LVTTL compatible input that places the device in power down mode when held low. All pin tri-state. .(S/W option) RESET in : LVTTL compatible input that places the device to initial state when held low.(S/W option) True Clock of differential pair...