DATASHEET
Frequency Generator and Integrated Buffers for Celeron & PII/IIITM
Recommended Application:
810/810E and 815 type chipset.
Pin Configuration
*FS2//REF0 VDD X1 X2 GND GND 3V66-0 3V66-1 3V66-2 VDD VDD PCICLK_F PCICLK0 GND PCICLK1 PCICLK2 GND PCICLK3 PCICLK4 PCICLK5 VDD VDD GND GND 48MHz_0 48MHz_1 VDD FS0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28
ICS9250-27
Output Features:
• • • • • • • 3 CPU (2.5V) (up to 133MHz achievable through I2C) 9 SDRAM (3.3V) (up to 133MHz achievable through I2C) 7 PCI (3.3 V) @33.3MHz 2 IOAPIC (2.5V) @ 33.3 MHz 3 Hublink clocks (3.3 V) @ 66.6 MHz 2 (3.3V) @ 48 MHz (Non spread spectrum) 1 REF (3.3V) @ 14.318 MHz
Features:
• • • • • Supports spread spectrum modulation, 0 to -0.5% down spread. I2C support for power management Efficient power management scheme through PD# Uses external 14.138 MHz crystal Alternate frequency selections available through I2C control.
56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29
GND IOAPIC0 IOAPIC1 VDDL CPUCLK0 VDDL0 CPUCLK1 CPUCLK2 GNDL GND SDRAM0 SDRAM1 VDD SDRAM2 SDRAM3 GND SDRAM4 SDRAM5 VDD SDRAM6 SDRAM7 GND SDRAM_F VDD PD# SCLK SDATA FS1
56-Pin 300mil SSOP
* This input has a 50KΩ pull-down to GND.
Block Diagram Functionality
X1 X2 XTAL OSC PLL1 Spread Spectrum REF0
FS2 X X
FS1 0 0 1 1 1 1
FS0 0 1 0 1 0 1
ICS9250-27
Function Tristate Test Active CPU = 66MHz SDRAM = 100MHz Active CPU = 100MHz SDRAM = 100MHz Active CPU = 133MHz SDRAM = 133MHz Active CPU = 133MHz SDRAM = 100MHz
/2
/3
VDDL CPU66/100/133 (2:0) 3
0 0 1 1
FS (2:0) PD#
Control Logic
3 8
3V66 (2:0) SDRAM (7:0) SDRAM_F
SDATA SCLK Config Reg
/2
6
PCICLK (5:0) PCICLK_F
/2 PLL2
2
IOAPIC (1:0) VDDL 48MHz (1:0)
Power Groups
AVDD = Pin 22 Analog power for PLL AGND = Pin 23 Analog ground VDD48 = Pin 27 Analog power for 48MHz PLL GND = Pin 24 Analog ground for 48MHz PLL
2
IDTTM Frequency Generator and Integrated Buffers for Celeron & PII/IIITM
0395F—01/25/10
1
ICS9250-27 Frequency Generator and Integrated Buffers for Celeron & PII/IIITM
General Description
The ICS9250-27 is a single chip clock solution for 810/810E and 815 type chipset. It provides all necessary clock signals for such a system. Spread spectrum may be enabled through I2C programming. Spread spectrum typically reduces EMI by 8dB to 10 dB. This simplifies EMI qualification without resorting to board design iterations or costly shielding. The ICS925027 employs a proprietary closed loop design, which tightly controls the percentage of spreading over process and temperature variations.
Pin Description
PIN NUMBER 1 3 4 PIN NAME FS2 REF0 X1 X2 TYPE IN OUT IN OUT PWR OUT PWR OUT OUT OUT OUT IN I/O IN IN OUT OUT OUT PWR OUT DESCRIPTION Function Select pin. Determines CPU frequency, all output functionality 3.3V, 14.318MHz reference clock output. Cr ystal input, has inter nal load cap (33pF) and feedback resistor from X2 Cr ystal output, nominally 14.318MHz. Has inter nal load cap (33pF) Ground pins for 3.3V supply 3.3V Fixed 66MHz clock outputs for HUB 3 . 3 V p ow e r s u p p l y Free r unning 3.3V PCI clock output 3.3V PCI clock outputs 3.3V Fixed 48MHz clock outputs for USB 3.3V fixed 48MHz clock output. Stronger output for graphics/video interface (minimum 1V/ns edge rate) Function Select pins. Determines CPU frequency, all output functionality. Please refer to Functionality table on page 1 Data pin for I2C circuitr y 5V tolerant Clock pin of I2C circuitr y 5V tolerant Asynchronous active low input pin used to power down the device into a low power state. The inter nal clocks are disabled and the VCO a n d t h e c r y s t a l a r e s t o p p e d . T h e l a t e n c y o f t h e p ow e r d ow n w i l l n o t b e g r e a t e r t h a n 3 m s. 3.3V output r unning 100MHz. All SDRAM outputs can be tur ned off t h r o u g h I 2C 3 . 3 V f r e e r u n n i n g 1 0 0 M H z S D R A M , c a n n o t b e t u r n e d o f f t h r o u g h I 2C 2.5V Host bus clock output. 66MHz, 100MHz or 133MHz depending o n F S p i n s. 2.5V power suypply for CPU & IOAPIC 2.5V clock outputs r unning at 33.3MHz.
5, 6, 14, 17, 23, 24, 35, 41, 47, GND 48, 56 9, 8, 7 2, 10, 11, 21, 22, 27, 33, 38, 44 12 20, 19, 18, 16, 15, 13 25 26 29, 28 30 31 32 36, 37, 39, 40, 42, 43, 45, 46 34 49, 50, 52 51, 53 54, 55 3V66 (2:0) VDD PCICLK_F PCICLK (5:0) 48MHz_0 48MHz_1 FS (1:0) SDATA SCLK PD# SDRAM (7:0) SDRAM_F CPUCLK (2:0) VDDL IOAPIC (1:0)
IDTTM Frequency Generator and Integrated Buffers for Celeron & PII/IIITM
0395F—01/25/10
2
ICS9250-27 Frequency Generator and Integrated Buffers for Celeron & PII/IIITM
Power Down Waveform
Note 1. After PD# is sampled active (Low) for 2 consective rising edges of CPUCLKs, all the output clocks are driven Low on their next High to Low tranistiion. 2. Power-up latency