AV9155C-44 Integrated Circuit Systems, Inc. Low Cost 20-Pin Frequency Generator General Description Features The AV9155C-44 is a low cost frequency generator designed specifically for desktop and notebook PC applications with either 3.3V or 5.0V power supply voltage. Its CPU clocks provide all necessary CPU frequencies for 286, 386 and 486 systems, including support for the latest speeds of processors. The device uses a 14.318 MHz crystal to generate the CPU and all peripheral clocks for integrated desktop motherboards. The dual 14.318 MHz clock outputs allows one output for the system and one to be the input to an ICS graphics frequency generator such as the AV9194. The CPU clock offers the unique feature of smooth, glitchfree transitions from one frequency to the next, making this ideal device to use whenever slowing the CPU speed. The AV9155C-44 makes a gradual transition between frequencies, so that it obeys the Intel cycle-to-cycle timing specification for 486 systems. The simultaneous 2X and 1X CPU clocks offer controlled skew to within 1.5ns (max) of each other. Block Diagram Compatible with 286, 386, and 486 CPUs Supports turbo modes Generates communications clock, keyboard clock, floppy disk clock, system reference clock, bus clock and CPU clock Output enable tristates outputs Up to 100 MHz at 5V or 3.3V 20-pin DIP or SOIC All loop filter components internal Skew-controlled 2X and 1X CPU clocks Power-down option Pin Configuration 20-Pin DIP or SOIC THIS DATA SHEET (AV9155C-44) IS AN ADDENDUM TO THE EXISTING AV9155C DATA SHEET. ALL INFORMATION IN THIS DATA SHEET SUPERSEDES THE DATA FOUND IN THE ORIGINAL AV9155C DATA SHEET. 9155-44 Rev D 02/12/98 ICS reserves the right to make changes in the device data identified in this publication without further notice. ICS advises its customers to obtain the latest version of all device data to verify that any information being relied upon by the customer is current and accurate. AV9155C-44 Pin Descriptions for AV9155C-44 PIN NUMBER 1 2 3 4 5 6 7 8 9 10 PIN NAME 3.529 MHz X2 X1 VDD GND 20 MHz N/C 30 MHz AGND N/C 11 OE# 12 13 14 15 16 17 18 19 20 N/C 16 MHz N/C GND VDD 2XCPU N/C FS1 FS0 TYPE OUT OUT IN PWR PWR OUT OUT PWR IN OUT PWR PWR OUT IN IN DESCRIPTION 3.529 MHz reference clock output. CRYSTAL connection. CRYSTAL connection. DIGITAL POWER SUPPLY (+5V). Digital GROUND. 20 MHz clock output. Not internally connected. 30 MHz keyboard clock output. ANALOG GROUND (original version). Not internally connected. OUTPUT ENABLE. Tristates 2XCPU output when high. (Has internal pull-up.) Not internally connected. 16 MHz reference clock output. Not internally connected. Digital GROUND. DIGITAL POWER SUPPLY (+5V). CPU clock output. Not internally connected. CLOCK frequency SELECT #1. (Has internal pull-up.) CLOCK frequency SELECT #0. (Has internal pull-up.) 2 AV9155C-44 Functionality (Using 16.0 MHz input.All frequencies in MHz.) CPU FS1 (Pin 19) FS0 (Pin 20) 2XCPU (Pin 17) 0 0 20.0 0 1 28.0 1 0 22.59 1 1 39.38 (Pin 1) (Pin 6) (Pin 8) 3.529 Mhz 20 MHz 30 MHz * 5V only PERIPHERAL CLOCKS REFERENCE CLOCKS (Pin 13) 16 Mhz Specification Limits (superseding AV9155C general data sheet) No internal capacitors on crystal pins X1 and X2. PARAMETER Jitter, One Sigma,1 all clocks 20 to 40 MHz Jitter, One Sigma,1 clocks below 20 MHz Jitter, Absolute, all clocks 20 to 40 MHz Jitter, Absolute,1 all clocks below 20 MHz SYMBOL TEST CONDITIONS MIN TYP MAX UNITS tj1sa 10,000 cycles 500 ps tj1sb 10,000 cycles 2.0 % tjabsa 10,000 cycles -1000 1000 ps tjabsb 10,000 cycles -3.0 3.0 % Note: Parameter is guaranteed by design and characterization, not subject to production testing. 3 AV9155C-44 SOIC LEAD COUNT 20L DIMENSION L 0.504 20 Pin DIP Ordering Information AV9155C-44CW20 Example: ICS XXXX-PPP M X#W Lead Count & Package Width Lead Count=1, 2 or 3 digits W=.3 SOIC or .6 DIP; None=Standard Width Package Type W=SOIC T&R=Tape and Reel Pattern Number (2 or 3 digit number for parts with ROM code patterns) Device Type (consists of 3 or 4 digit numbers) Prefix ICS, AV=Standard Device 4 ICS reserves the right to make changes in the device data identified in this publication without further notice. ICS advises its customers to obtain the latest version of all device data to verify that any information being relied upon by the customer is current and accurate.