Texas Instruments

The CDC318A is a high-performance clock buffer designed to distribute high-speed clocks in PC applications. This device distributes one input (A) to 18 outputs (Y) with minimum skew for clock distribution. The CDC318A operates from a 3.3-V power supply. It is characterized for operation from 0°C to 70°C. This device has been designed with consideration for optimized EMI performance. Depending on the application layout, damping resistors in series to the clock outputs (like proposed in the PC100 specification) may not be needed in most cases. 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) are 5-V tolerant and provide integrated pullup resistors (typically 140 k). 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 CDC318A 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 CDC318A is a high-performance clock buffer designed to distribute high-speed clocks in PC applications. This device distributes one input (A) to 18 outputs (Y) with minimum skew for clock distribution. The CDC318A operates from a 3.3-V power supply. It is characterized for operation from 0°C to 70°C. This device has been designed with consideration for optimized EMI performance. Depending on the application layout, damping resistors in series to the clock outputs (like proposed in the PC100 specification) may not be needed in most cases. 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) are 5-V tolerant and provide integrated pullup resistors (typically 140 k). 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 CDC318A 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 CDC328A contains a clock-driver circuit that distributes one input signal to six outputs with minimum skew for clock distribution. Through the use of the polarity-control inputs (T\/C), various combinations of true and complementary outputs can be obtained. The CDC328A is characterized for operation from -40°C to 85°C. The CDC328A contains a clock-driver circuit that distributes one input signal to six outputs with minimum skew for clock distribution. Through the use of the polarity-control inputs (T\/C), various combinations of true and complementary outputs can be obtained. The CDC328A is characterized for operation from -40°C to 85°C.

The CDC329A contains a clock-driver circuit that distributes one input signal to six outputs with minimum skew for clock distribution. Through the use of the polarity-control inputs (T\/C), various combinations of true and complementary outputs can be obtained. The CDC329A is characterized for operation from -40°C to 85°C. The CDC329A contains a clock-driver circuit that distributes one input signal to six outputs with minimum skew for clock distribution. Through the use of the polarity-control inputs (T\/C), various combinations of true and complementary outputs can be obtained. The CDC329A is characterized for operation from -40°C to 85°C.

The CDC340 is a high-performance clock-driver circuit that distributes one (A) input signal to eight (Y) outputs with minimum skew for clock distribution. Through the use of the control pins (1G and 2G), the outputs can be placed in a high state regardless of the A input. The propagation delays are adjusted at the factory using the P0 and P1 pins. These pins are not intended for customer use and should be strapped to GND. The CDC340 is characterized for operation from 0°C to 70°C. The CDC340 is a high-performance clock-driver circuit that distributes one (A) input signal to eight (Y) outputs with minimum skew for clock distribution. Through the use of the control pins (1G and 2G), the outputs can be placed in a high state regardless of the A input. The propagation delays are adjusted at the factory using the P0 and P1 pins. These pins are not intended for customer use and should be strapped to GND. The CDC340 is characterized for operation from 0°C to 70°C.