CALIFORNIA MICRO DEVICES

PACDN005

2/00

1

215 Topaz Street, Milpitas, California 95035

Tel: (408) 263-3214

Fax: (408) 263-7846

www.calmicro.com

©2000 California Micro Devices Corp. All rights reserved.

Features

• 36 integrated diodes in a single package

offers 18 channel, dual rail clamping action

• Provides proper bus termination independent of

external line or card loading conditions

• Schottky diode technology; excellent forward

voltage and reverse recovery characteristics

• 24-pin QSOP package saves board space and

eases layout in space critical bus termination

applications versus discrete approaches

Product Description

Note: CMD’s P/Active DN005 Schottky Diode High Speed Bus Terminator is an upgraded version of the original PDN001 or

IPEC DN001 Diode Array. PACDN005 provides minimized lead inductance and parasitic capacitive effects (with added ground

pins), improved forward voltage and crosstalk attributes, and excellent termination performance characteristics at high data

transmission rates. The PACDN005 is recommended for all new designs.

Reflections on high speed data lines lead to undershoot and overshoot disturbances which may result in improper system

operation. Resistor terminations, when used to terminate high speed data lines, increase power consumption and degrade

output (high) levels resulting in reduced noise immunity. Schottky diode termination is the best overall solution for applica-

tions in which power consumption and noise immunity are critical considerations.

shoot disturbances caused by reflection noise on high speed bus lines such as v2.1 66MHz PCI buses, all varieties of RISC

embedded processor/control local buses, synchronous DRAM, and other high speed memory bus termination applications.

This highly integrated Schottky diode network provides very effective termination performance for high speed data lines under

variable loading conditions. The device supports up to 18 terminated lines per package — each of which can be simulta-

neously clamped to both ground and power supply rail. A typical bus termination application will utilize three PAC DN005

devices to replace approximately 50 conventional Schottky diode pairs; thus providing significant reductions in component

and assembly costs, improvements in manufacturing efficiency and reliability, and savings in allocated board area for space-

critical designs.

Applications

• PCI v2.1 Bus Termination for Intel-based Pentium®

and Pentium Pro systems

• Local high speed bus termination for all popular

RISC and embedded microprocessor applications

• High speed memory and SDRAM Memory

Bus Termination

P/ACTIVE SCHOTTKY DIODE HIGH SPEED BUS TERMINATOR

Refer to AP-201 Termination Application Note for

further information.

SCHEMATIC CONFIGURATION

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2

3

4

5

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10

11

12

23

22

21

20

19

18

13

14

17

15

16

VDD

VDD

VDD

GND

GND

GND