CDC319 1-LINE TO 10-LINE CLOCK DRIVER WITH I²C CONTROL INTERFACE

SCAS590 - DECEMBER 1997

features

• High-Speed, Low-Skew 1-to-10 Clock Buffer for SDRAM (Synchronous DRAM) Clock Buffering Applications
• Output Skew, t_sk(o), Less Than 250 ps
• Pulse Skew, t_sk(p), Less Than 500 ps
• Supports up to Two Unbuffered SDRAM DIMMs (Dual Inline Memory Modules)
• I²C Serial Interface Provides Individual Enable Control for Each Output
• Operates at 3.3 V
• Distributed V_CC and Ground Pins Reduce Switching Noise
• ESD Protection Exceeds 2000 V Per MIL-STD-883, Method 3015
• Packaged in 28-Pin Shrink Small Outline (DB) Package

  Intel is a trademark of Intel Corporation

description

The CDC319 is a high-performance clock buffer that distributes one input (A) to 10 outputs (Y) with minimum skew for clock distribution. The CDC319 operates from a 3.3-V power supply, and is characterized for operation from 0°C to 70°C.

The device provides a standard mode (100K-bits/s) I²C serial interface for device control. The implementation is as a slave/receiver. The device address is specified in the I²C device address table. Both of the I²C inputs (SDATA and SCLOCK) provide integrated pullup resistors (typically 140 kΩ) and are 5-V tolerant.

Three 8-bit I²C registers provide individual enable control for each of the outputs. All outputs default to enabled at powerup. Each output can be placed in a disabled mode with a low-level output when a low-level control bit is written to the control register. The registers are write only and must be accessed in sequential order (i.e., random access of the registers is not supported).

The CDC319 provides 3-state outputs for testing and debugging purposes. The outputs can be placed in a high-impedance state via the output-enable (OE) input. When OE is high, all outputs are in the operational state. When OE is low, the outputs are placed in a high-impedance state. OE provides an integrated pullup resistor.

^† The function table assumes that all outputs are enabled via the appropriate I²C configuration register bit. If the output is disabled via the appropriate configuration bit, then the output is driven to a low state, regardless of the state of the A input.

View more information about generic part numbers:CDC319

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