Integrated Circuit Systems, Inc. ICS9248-50 Frequency Timing Generator for Pentium II Systems General Description Features The ICS9248-50 is the Main clock solution for Notebook designs using the Intel 440BX style chipset. Along with an SDRAM buffer such as the ICS9179-03, it provides all necessary clock signals for such a system. Spread spectrum may be enabled by driving pin 26, SPREAD# active (Low) at power-on. Spread spectrum typically reduces system EMI by 8dB to 10dB. This simplifies EMI qualification without resorting to board design iterations or costly shielding. The ICS9248-50 employs a proprietary closed loop design, which tightly controls the percentage of spreading over process and temperature variations. Block Diagram Generates the following system clocks: - 2CPU(2.5V) up to 100MHz. - 6 PCI(3.3V) @ 33.3MHz (Includes one free running). - 2 REF clks (3.3V) at 14.318MHz. Skew characteristics: - CPU CPU<175ps - PCI PCI < 500ps - CPU(early) PCI = 1.5ns 4ns. Supports Spread Spectrum modulation for CPU and PCI clocks, 0.5% down spread Efficient Power management scheme through stop clocks and power down modes. Uses external 14.318MHz crystal, no external load cap required for CL=18pF crystal. 28-pin (209 mil) SSOP and (6.1mm) TSSOP package Pin Configuration 28-Pin SSOP & TSSOP Power Groups VDD, GND = PLL core VDDREF, GNDREF = REF(0:1), X1, X2 VDDPCI, GNDPCI = PCICLK_F, PCICLK (0:4) VDD48, GND48 = 48MHz, 48/24MHz Pentium is a trademark on Intel Corporation. 9248-50 Rev - E 6/3/99 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. ICS9248-50 Pin Descriptions Pin number Pin name Type Description 1 2 3 4 5,6,9,10,11 7 8 12 13 GNDREF X1 X2 PCICLK_F PCICLK (1:5) GNDPCI VDDPCI VDD48 48 MHz Power Input Output Output Output Power Power Power Output 14 TS#/48/24MHz Output 15 GND48 Power 16 SEL 100/66# Input 17 PD# Input 18 CPU_STOP# Input 19 VDD Power 20 PCI-Stop# Input 21 22 23,24 25 GND GNDL CPUCLK(1:0) VDDL Power Power Output Power 26 REF1/SPREAD# Output 27 REF0/SEL48# Output 28 VDDREF Power Ground for 14.318 MHz reference clock outputs 14.318 MHz crystal input 14.318 MHz crystal output 3.3 V free running PCI clock output, will not be stopped by the PCI_STOP# 3.3 V PCI clock outputs, generating timing requirements for Pentium II Ground for PCI clock outputs 3.3 V power for the PCI clock outputs 3.3 V power for 48/24 MHz clocks 3.3 V 48 MHz clock output, fixed frequency clock typically used with USB devices 3.3 V 48 or 24 MHz output and Tri-state option, active low = tri state mode for testing, active high = normal operation Ground for 48/24 MHz clocks control for the frequency of clocks at the CPU & PCICLK output pins. If logic "0" is used the 66.6 MHz frequency is selected. If Logic "1" is used, the 100 MHz frequency is selected. The PCI clock is multiplexed to run at 33.3 MHz for both selected cases. Asynchronous active low input pin used to power down the device into a low power state. The internal clocks are disabled and the VCO and the crystal are stopped. The latency of the power down will not be greater than 3ms. Asynchronous active low input pin used to stop the CPUCLK in active low state, all other clocks will continue to run. The CPUCLK will have a "Turnon " latency of at least 3 CPU clocks. Isolated 3.3 V power for core Synchronous active low input used to stop the PCICLK in active low state. It will not effect PCICLK_F or any other outputs. Isolated ground for core Ground for CPU clock outputs 2.5 V CPU clock outputs 2.5 V power for CPU clock outputs 3.3 V 14.318 MHz reference clock output and power-on spread spectrum enable option. Active low = spread spectrum clocking enable. Active high = spread spectrum clocking disable. 3.3 V 14.318 MHz reference clock output and power-on 48/24 MHz select option. Active low = 48 MHz output at pin 14. Active high = 24 MHz output at pin 14. 3.3 V power for 14.318 MHz reference clock outputs. 2 ICS9248-50 Select Functions (Functionality determined by TS# and SEL100/66# pin, see below) Functionality PCI, PCI_F CPUCLK REF0 Tristate HI - Z HI - Z HI - Z Testmode TCLK/21 TCLK/61 TCLK1 Notes: 1. TCLK is a test clock driven on the X1 (crystal in pin) input during test mode. SEL 100/66# TS# Function 0 0 Tri-State 0 - (Reserved) 0 - (Reserved) 0 1 Active 66.6MHz CPU, 33.3 PCI 1 0 Test Mode 1 - (Reserved) 1 - (Reserved) 1 1 Active 100MHz CPU, 33.3 PCI Power Management Clock Enable Configuration C P U _ S TO P # P C I _ S TO P # X X 0 0 0 1 1 0 1 1 P W R _ DW N # 0 1 1 1 1 CPUCLK L ow Low Low 100/66.6MHz 100/66.6MHz PCICLK PCICLK_F L ow L ow Low 33.3MHz 33.3 MHz 33.3MHz Low 33.3MHz 33.3 MHz 33.3MHz REF Stopped Running Running Running Running Crystal O ff Running Running Running Running VCOs O ff Running Running Running Running Full clock cycle timing is guaranteed at all times after the system has initially powered up except where noted. During power up and power down operations using the PD# pin will not cause clocks of a short or longer pulse than that of the running clock. The first clock pulse coming out of a stopped clock condition may be slightly distorted due to clock network charging circuitry. Board routing and signal loading may have a large impact on the initial clock distortion also. ICS9248-50 Power Management Requirements SIGNAL SIGNAL STATE C P U _ S TO P # 0 (Disabled)2 1 (Enabled)1 0 (Disabled)2 1 (Enabled)1 1 (Normal Operation)3 0 (Power Down)4 P C I _ S TO P # PD# L a t e n cy No. of rising edges of free running PCICLK 1 1 1 1 3ms 2max Notes. 1. Clock on latency is defined from when the clock enable goes active to when the first valid clock comes out of the device. 2. Clock off latency is defined from when the clock enable goes inactive to when the last clock is driven low out of the device. 3. Power up latency is when PD# goes inactive (high) to when the first valid clocks are output by the device. 4. Power down has controlled clock counts applicable to CPUCLK, PCICLK only. The REF will be stopped independant of these. 3 ICS9248-50 CPU_STOP# Timing Diagram CPUSTOP# is an asychronous input to the clock synthesizer. It is used to turn off the CPUCLKs for low power operation. CPU_STOP# is synchronized by the ICS9248-50. The minimum that the CPUCLK is enabled (CPU_STOP# high pulse) is 100 CPUCLKs. All other clocks will continue to run while the CPUCLKs are disabled. The CPUCLKs will always be stopped in a low state and start in such a manner that guarantees the high pulse width is a full pulse. CPUCLK on latency is less than 4 CPUCLKs and CPUCLK off latency is less than 4 CPUCLKs. Notes: 1. All timing is referenced to the internal CPUCLK. 2. CPU_STOP# is an asynchronous input and metastable conditions may exist. This signal is synchronized to the CPUCLKs inside the ICS9248-50. 3. All other clocks continue to run undisturbed. 4. PD# and PCI_STOP# are shown in a high (true) state. PCI_STOP# Timing Diagram PCI_STOP# is an asynchronous input to the ICS9248-50. It is used to turn off the PCICLK (0:4) clocks for low power operation. PCI_STOP# is synchronized by the ICS9248-50 internally. The minimum that the PCICLK (0:4) clocks are enabled (PCI_STOP# high pulse) is at least 10 PCICLK (0:4) clocks. PCICLK (0:4) clocks are stopped in a low state and started with a full high pulse width guaranteed. PCICLK (0:4) clock on latency cycles are only one rising PCICLK clock off latency is one PCICLK clock. Notes: 1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS9248 device.) 2. PCI_STOP# is an asynchronous input, and metastable conditions may exist. This signal is required to be synchronized inside the ICS9248. 3. All other clocks continue to run undisturbed. 4. PD# and CPU_STOP# are shown in a high (true) state. 4 ICS9248-50 PD# Timing Diagram The power down selection is used to put the part into a very low power state without turning off the power to the part. PD# is an asynchronous active low input. This signal is synchronized internally by the ICS9248-50 prior to its control action of powering down the clock synthesizer. Internal clocks will not be running after the device is put in power down state. When PD# is active (low) all clocks are driven to a low state and held prior to turning off the VCOs and the crystal oscillator. The power on latency is guaranteed to be less than 3ms. The power down latency is less than three CPUCLK cycles. PCI_STOP# and CPU_STOP# are dont care signals during the power down operations. Notes: 1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS9248 device). 2. PD# is an asynchronous input and metastable conditions may exist. This signal is synchronized inside the ICS9248. 3. The shaded sections on the VCO and the Crystal signals indicate an active clock is being generated. 5 ICS9248-50 Absolute Maximum Ratings Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . 7.0 V Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . GND 0.5 V to VDD +0.5 V Ambient Operating Temperature . . . . . . . . . . . . 0C to +70C Storage Temperature . . . . . . . . . . . . . . . . . . . . . . 65C to +150C Stresses above those listed under Absolute Maximum Ratings may cause permanent damage to the device. These ratings are stress specifications only and functional operation of the device at these or any other conditions above those listed in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect product reliability. Electrical Characteristics - Input/Supply/Com m on O utput Param eters T A = 0 - 70C; Supply Voltage VD D = 3.3 V +/-5% , VD D L = 2.5 V +/-5% (unles s otherwis e s tated) PAR AM ETER Input High Voltage Input Low Voltage Input High C urrent Input Low Current Input Low Current Operating Supply C urrent Power Down Supply C urrent Input frequency Input C apacitance 1 Transition Time 1 Clk Stabilization Skew 1 1 SYM B OL V IH V IL IIH IIL1 IIL2 IDD3 .3 OP6 6 IDD3 .3 OP1 0 0 ID D 2 .5 O P 6 6 ID D 2 .5 O P 1 0 0 IDD3 .3 PD C ONDITIONS V IN = V DD V IN = 0 V; Inputs with no pull-up resisto rs V IN = 0 V; Inputs with pu ll-up resistors C L = 0 pF; Select @ 66M Hz C L = 0 pF; Select @ 100M Hz CL = 0 pF; Select @ 66.8 M Hz CL = 0 pF; Select @ 100 M Hz M IN 2 V SS -0.3 -5 -200 C L = 0 pF; With input address to Vdd or GND TYP 0.1 2.0 -100 60 66 16 23 M AX UNITS V DD+0.3 V 0.8 V A 5 A A 180 mA 180 mA 72 mA 100 mA 70 600 A V DD = 3.3 V; 11 14.318 16 M Hz C IN C INX Logic Inputs X1 & X2 pins 27 36 5 45 pF pF T tran s To 1st crossing of target Freq. 3 ms 3 ms 4 ns Fi T STAB T CPU-PCI From V DD = 3.3 V to 1% target Freq. VT = 1.5 V; VTL = 1.25 V 6 1.5 3 ICS9248-50 Electrical Characteristics - CPUCLK T A = 0 - 70C; V DD = 3.3 V +/-5%, VDDL = 2.5 V +/-5%; C L = 10 - 20 pF (unless otherwise stated) PARAM ETER Output High Voltage Output Low Voltage Output High Current Output Low Current CONDITIONS IOH = -12.0 mA IOL = 12 mA VOH = 1.7 V VOL = 0.7 V M IN 1.8 TYP 2.3 0.31 M AX 0.4 -27 27 UNITS V V mA mA t r2 B 1 VOL = 0.4 V, VOH = 2.0 V 0.4 1.15 1.6 ns Fall Time t f2 B 1 VOH = 2.0 V, VOL = 0.4 V 0.4 1.4 1.6 ns Duty Cycle d t2 B 1 VT = 1.25 V 44 48 55 % 10 134 10 175 10.5 ps ns 186 250 ps 150 +250 ps Rise Time 1 Skew Jitter t sk 2 B VT = 1.25 V period(norm) VT = 1.25 V; 100M Hz Jitter, One Sigma Jitter, Absolute 1 SYM BOL VOH2 B VOL2 B IOH2 B IOL2B t jcy c-cy c2 B 1 t jab s 2 B 1 VT = 1.25 V VT = 1.25 V -250 Guaranteed by design, not 100% tested in production. Electrical Characteristics - REF/48M Hz/24M Hz T A = 0 - 70C; V DD = 3.3 V +/-5%, V DDL = 2.5 V +/-5%; C L = 10 - 20 pF (unless otherwise stated) PA RA M ETER Output High Voltage Output Low Voltage Output High Current Output Low Current Ris e Time Fall Time 1 1 Duty Cycle Jitter Jitter 1 1 1 SYM BOL VO H 5 VO L 5 IO H 5 IO L 5 CONDITIONS IO H = -12 mA IO L = 9 mA VO H = 2.0 V VO L = 0.8 V M IN 2.6 16 TYP 3.1 0.17 -44 42 M A X UNITS V 0.4 V -22 mA mA t r5 VO L = 0.4 V, VO H = 2.4 V 1.4 4 ns t f5 VO H = 2.4 V, VO L = 0.4 V 1.1 4 ns d t5 VT = 1.5 V t j1 5 t jab s5 t j1 5 t jab s5 45 VT = 1.5 V, REF VT = 1.5 V, REF VT = 1.5 V, 48 M Hz VT = 1.5 V, 48 M Hz 7 53 55 % 185 385 169 469 250 800 250 800 ps ps ps ps ICS9248-50 Electrical Characteristics - PCICLK TA = 0 - 70C; VD D = 3.3 V +/-5%, VD D L = 2.5 V +/-5%; CL = 30 pF PA RA M ETER Output High Voltage Output Low Voltage Output High Current Output Low Current Ris e Time Fall Time 1 1 Duty Cycle Skew Jitter 1 1 1 1 SYM BOL VO H 1 VO L 1 IO H 1 IO L 1 CONDITIONS IO H = -18 mA IO L = 9.4 mA VO H = 2.0 V VO L = 0.8 V M IN 2.1 TYP 3.3 0.1 16 M A X UNITS V 0.4 V -22 mA 57 mA t r1 VO L = 0.4 V, VO H = 2.4 V 1.6 2 ns t f1 VO H = 2.4 V, VO L = 0.4 V 1.8 2 ns d t1 VT = 1.5 V 50 55 % t sk 1 VT = 1.5 V VT = 1.5 V VT = 1.5 V VT = 1.5 V 222 186 52 200 500 500 150 500 ps ps ps ps t jcy c-cy c t j1 s t jab s 45 Guaranteed by des ign, not 100% tes ted in production. 8 ICS9248-50 General Layout Precautions: 1) Use a ground plane on the top layer of the PCB in all areas not used by traces. 2) Make all power traces and vias as wide as possible to lower inductance. Notes: 1 All clock outputs should have series terminating resistor. Not shown in all places to improve readibility of diagram 2 Optional EMI capacitor should be used on all CPU, SDRAM, and PCI outputs. 3 Optional crystal load capacitors are recommended. Capacitor Values: C1, C2 : Crystal load values determined by user All unmarked capacitors are 0.01F ceramic 9 ICS9248-50 COMMON DIMENSIONS SYMBOL D VARIATIONS MIN. NOM. MAX. N MIN. NOM. MAX. A A1 A2 b c D E e H L N 0.068 0.002 0.066 0.010 0.004 0.078 0.008 0.070 0.015 0.008 14 16 20 24 28 30 0.239 0.239 0.278 0.318 0.397 0.397 0.244 0.244 0.284 0.323 0.402 0.402 0.249 0.249 0.289 0.328 0.407 0.407 0 0.073 0.005 0.068 0.012 0.006 See Variations 0.209 0.0256 BSC 0.307 0.030 See Variations 4 0.205 0.301 0.025 0.212 0.311 0.037 Dimensions in inches 8 Ordering Information ICS9248yF-50 Example: ICS XXXX y F - PPP Pattern Number (2 or 3 digit number for parts with ROM code patterns) Package Type F=SSOP Revision Designator Device Type (consists of 3 or 4 digit numbers) Prefix ICS, AV = Standard Device 10 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. ICS9248-50 SYMBOL COMMON DIMENSIONS VARIATIONS D MIN. NOM. MAX. MIN. NOM. MAX. A 1.10 DB 9.60 9.70 9.80 A1 0.05 0.15 A2 0.85 0.90 0.95 aaa 0.10 b 0.19 0.30 b1 0.19 0.22 0.25 bbb 0.10 C 0.09 0.20 C1 0.09 0.16 D See Variations E 6.00 6.10 6.20 e 0.65 BSC H 8.10 BSC L 0.50 0.60 0.75 N See Variations 0 8 Ordering Information ICS9248yG-50 Example: ICS XXXX y G - PPP N 28 Pattern Number (2 or 3 digit number for parts with ROM code patterns) Package Type G=TSSOP Revision Designator Device Type (consists of 3 or 4 digit numbers) Prefix ICS, AV = Standard Device 11 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. Page 1 of 2 Global Sites Search Entire Site Contact IDT | Investors | Press Email | Print Document Search | Package Search | Parametric Search | Cross Reference Search | Green & RoHS | Calculators | Thermal Data | Reliability & Quality | Military Home > Products > Timing Solutions > PC-Notebook-Server Clocks > Clock Synthesizer by Chipset Vendor > Notebook Chipsets > 9248-92 You may also like... Add to myIDT [?] 9248-92 (Notebook Chipsets) Description The ICS9248-92 is a fully compliant timing solution for the Intel mobile 440BX/MX chipset requirements. Market Group PC CLOCK Additional Info General Description: Features include two strong CPU, seven PCI and eight SDRAM clocks. Three reference outputs are available equal to the crystal frequency. Stronger drive CPUCLK outputs typically provide greater than 1 V/ns slew rate into 20pF loads. This device meets rise and fall requirements with 2 loads per CPU output (ie, one clock to CPU and NB chipset, one clock to two L2 cache inputs). Related Orderable Parts Attributes 9248AG-92 9248AG-92LF 9248AG-92LFT 9248AG-92T Voltage 3.3 V (PA48) 3.3 V (PAG48) 3.3 V (PAG48) 3.3 V (PA48) Package TSSOP 48 TSSOP 48 TSSOP 48 TSSOP 48 NA NA NA NA C C C C Status Active Active Active Active Sample No Yes No No Minimum Order Quantity 76 76 1000 1000 Factory Order Increment 38 38 1000 1000 Speed Temperature Related Documents Type Title Datasheet 9248-92 Datasheet Size 342 KB Revision Date 03/24/2006 9248-92 IBIS Model 166 KB 03/24/2006 Home | Site Map | About IDT | Press Room | Investor Relations | Trademark | Privacy Policy | Careers | Register | Contact Us mhtml:file://C:\9248-92.mht 08-Jun-2007 Page 2 of 2 Use of this website signifies your agreement to the acceptable use and privacy policy. Copyright 1997-2007 Integrated Device Technology, Inc. All Rights Reserved. Node: www.idt.com mhtml:file://C:\9248-92.mht 08-Jun-2007