UPD72852 データシートの表示（PDF） - NEC => Renesas Technology

部品番号

コンポーネント説明

一致するリスト

UPD72852

IEEE1394a-2000 COMPLIANT 400 Mbps TWO-PORT PHY LSI

NEC => Renesas Technology 

µPD72852

3.4 PLL and Crystal Oscillation Circuit

3.4.1 Crystal Oscillation Circuit

To supply the clock of 24.576 MHz ± 100 ppm, use an external capacitor of 10 pF and a crystal of 50 ppm.

3.4.2 PLL

The crystal oscillator multiplies the 24.576 MHz frequency by 16 (393.216 MHz).

3.5 CMC

CMC shows the bus manager function which corresponds to the c bit of the Self_ID packet and the Contender bit

in the PHY register when the input is High.

The value of CMC can be changed with software through the Link layer; this pin sets the initial value during Power-

on Reset. Use a pull-up or pull-down resistor of 10 kΩ, based on the device’s specification.

3.6 PC0-PC2

The PC0-PC2 pin corresponds to the power field of the Self_ID packet and Pwr_class in the PHY register. Refer to

Section 4.3.4.1 of the IEEE1394a-2000 specification for information regarding the Pwr_class. The value of Pwr can

be changed with software through the Link layer controller; this pin sets the initial value during Power-on Reset. Use

a pull-up or pull-down resistor of 10 kΩ based on the application.

3.7 RESETB

Connect an external capacitor of 0.1 µF between the RESETB pin and GND. If the voltage drops below 0 V, a

reset pulse is generated. All of the circuits are initialized, including the contents of the PHY register.

3.8 RI1

Connect an external resistor of 9.1 kΩ between the RI1 pin and GND to limit the LSI’s current.

Data Sheet S14920EJ3V0DS

19

Share Link: