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Integrated Circuit Systems, Inc. ICS9248-78 Preliminary Product Preview Frequency Timing Generator for Pentium II Systems General Description The ICS9248-78 is a single chip clock for Intel Pentium II. 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 ICS9248-78 employs a proprietary closed loop design, which tightly controls the percentage of spreading over process and temperature variations. Features Generates the following system clocks: - 2 - CPUs @ 2.5V, up to 150MHz. - 1 - IOAPIC @ 2.5V, PCI/2MHz. - 9 SDRAMs (3.3V), up to150MHz. -2 - 3V66 @ 3.3V, 2x PCIMHz. - 8 - PCIs @ 3.3V. - 1 - 48MHz, @ 3.3V fixed. - 2 - REF @ 3.3V, 14.318Hz. - 1 - 24MHz, @ 3.3V fixed. Supports spread spectrum modulation , down spread 0 to -0.5%, 0.25% center spread. I2C support for power management. Efficient power management scheme through PD#. Uses external 14.138 MHz crystal. Block Diagram Pin Configuration 48-Pin 300 mil SSOP Power Groups GNDREF, VDDREF = REF, Crystal GND3V66, VDD3V66 = 3V66 GNDPCI, VDDPCI = PCICLKs GNDCOR, VDDCOR = PLLCORE GND48, VDD48 = 48 GNDSDR, VDDSDR = SDRAM GNDLCPU, VDDLCPU = CPUCLK GNDLPCI, VDDLAPIC = IOAPIC 9248-78 Rev A 7/21/99 1. These pins will have 2X drive strength. * 120K ohm pull-up to VDD on indicated inputs. Pentium II is a trademark of Intel Corporation I2C is a trademark of Philips Corporation PRODUCT PREVIEW documents contain information on new products in the sampling or preproduction phase of development. Characteristic data and other specifications are subject to change without notice. ICS9248-78 Preliminary Product Preview Pin Descriptions PIN NUMBER 1 2, 9, 10, 18, 25, 29, 37 3 4 P I N NA M E REF1 VDD X1 X2 TYPE OUT PWR IN OUT PWR OUT OUT IN OUT IN OUT IN IN IN OUT IN IN OU T OUT OUT PWR OUT PWR OUT IN OUT DESCRIPTION 3.3V, 14.318MHz reference clock output. 3.3V power supply Crystal input, has internal load cap (33pF) and feedback resistor from X2 Crystal output, nominally 14.318MHz. Has internal load cap (33pF) Ground pins for 3.3V supply 3.3V clock outputs for HUB running at 2XPCI MHz 3.3V PCI clock outputs, with Synchronous CPUCLKS Logic input frequency select bit. Input latched at power on. 3.3V PCI clock outputs, with Synchronous CPUCLKS Logic input frequency select bit. Input latched at power on. 3.3V PCI clock outputs, with Synchronous CPUCLKS 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. Clock input of I2C input Data input for I2C serial input. 3 . 3 V F i xe d 4 8 M H z c l o c k o u t p u t f o r U S B Logic input frequency select bit. Input latched at power on. Logic input frequency select bit. Input latched at power on. 3 . 3 V fi x e d 2 4 M H z o u t p u t 3.3V free running SDRAM not affected by I2C 3.3V outputs Ground for 2.5V power supply for CPU & APIC 2 . 5 V H o s t bu s c l o c k o u t p u t . 2.5V power suypply for CPU, IOAPIC 2.5V clock outputs running at PCI/2 MHz This pin selects the 3V66 output frequency. 3.3V, 14.318MHz reference clock output. 5, 6, 14, 21, 28, GND 33, 41 7, 8 3V66 (1:0) 11 12 13, 15, 16, 17, 19, 20 22 23 24 26 PCICLK0 FS0 FS1 PCICLK (2:7) PD# SCLK SDATA 48MHz FS3 FS2 24MHz SDRAM_F SDRAM (7:0) GNDL CPUCLK (1:0) VDDL IOAPIC SEL_3V66 REF01 1 PCICLK11 27 30 40, 39, 38, 36, 35, 34, 32, 31 42 43, 44 45, 47 46 48 Note: 1. These pins will have 2X drive strength. 2 ICS9248-78 Preliminary Product Preview Frequency Selection FS3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 FS2 0 0 0 0 1 1 1 1 0 0 0 0 1 1 1 1 FS1 0 0 1 1 0 0 1 1 0 0 1 1 0 0 1 1 FS0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 CPU SDRAM PCI MHz MHz MHz 100.23 100.90 105.00 66.89 120.00 124.00 133.30 133.30 140.00 150.00 114.99 70.00 75.00 83.31 90.00 95.00 100.23 100.90 105.00 100.33 120.00 124.00 133.30 133.30 140.00 150.00 114.99 105.00 112.50 124.96 90.00 95.00 33.41 33.63 35.00 33.44 40.00 41.33 44.43 33.32 35.00 37.50 38.33 35.00 37.50 41.65 30.00 31.67 3V66 MHz SEL_3V66=0 66.82 67.26 70.00 66.89 64.00* 64.00* 64.00* 66.65 70.00 64.00* 64.00* 70.00 64.00* 64.00* 60.00 63.33 SEL_3V66=1 66.82 67.26 70.00 66.89 80.00 82.66 88.86 66.65 70.00 75.00 76.66 70.00 75.00 83.31 60.00 63.33 16.70 16.81 17.50 16.72 20.00 20.67 22.21 16.66 17.50 18.75 19.16 17.50 18.75 20.83 15.00 15.83 IOAPIC MHz Note: * These output frequencies are not synchronous to CPUCLK and do not have spread spectrum modulation. Clock Enable Configuration PD# 0 1 CPUCLK LOW ON SDRAM LOW ON IOAPIC LOW ON 66MHz LOW ON PCICLK LOW ON REF, 48MHz LOW ON Osc OFF ON VCOs OF F ON 3 ICS9248-78 Preliminary Product Preview 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 <3ms. 3. Waveform shown for 100MHz 4 ICS9248-78 Preliminary Product Preview General I2C serial interface information The information in this section assumes familiarity with I2C programming. For more information, contact ICS for an I2C programming application note. How to Write: Controller (host) sends a start bit. Controller (host) sends the write address D2 (H) ICS clock will acknowledge Controller (host) sends a dummy command code ICS clock will acknowledge Controller (host) sends a dummy byte count ICS clock will acknowledge Controller (host) starts sending first byte (Byte 0) through byte 5 ICS clock will acknowledge each byte one at a time. Controller (host) sends a Stop bit How to Read: Controller (host) will send start bit. Controller (host) sends the read address D3 (H) ICS clock will acknowledge ICS clock will send the byte count Controller (host) acknowledges ICS clock sends first byte (Byte 0) through byte 5 Controller (host) will need to acknowledge each byte Controller (host) will send a stop bit How to Write: Controller (Host) Start Bit Address D2(H) Dummy Command Code ICS (Slave/Receiver) How to Read: Controller (Host) Start Bit Address D3(H) ICS (Slave/Receiver) ACK ACK Dummy Byte Count ACK Byte Count ACK ACK Byte 0 Byte 0 ACK Byte 1 ACK Byte 1 ACK Byte 2 ACK Byte 2 ACK Byte 3 ACK Byte 3 ACK Byte 4 ACK Byte 4 ACK Byte 5 ACK Byte 5 ACK Stop Bit ACK Stop Bit Notes: 1. 2. 3. 4. 5. The ICS clock generator is a slave/receiver, I2C component. It can read back the data stored in the latches for verification. Read-Back will support Intel PIIX4 "Block-Read" protocol. The data transfer rate supported by this clock generator is 100K bits/sec or less (standard mode) The input is operating at 3.3V logic levels. The data byte format is 8 bit bytes. To simplify the clock generator I2C interface, the protocol is set to use only "Block-Writes" from the controller. The bytes must be accessed in sequential order from lowest to highest byte with the ability to stop after any complete byte has been transferred. The Command code and Byte count shown above must be sent, but the data is ignored for those two bytes. The data is loaded until a Stop sequence is issued. At power-on, all registers are set to a default condition, as shown. 6. 5 ICS9248-78 Preliminary Product Preview Byte 0: Functionality and frequency select register (Default=0) (1 = enable, 0 = disable) Bit Bit 7 0 - 0.25% Center Sperad Spectrum 1-Down Spread Spectrum 0 to -0.5% Bit CPUCLK SDRAM PCICLK (2, 6:4) MHz MHz MHz 0000 0001 0010 0011 0100 0101 Bit (2, 6:4) 0110 0111 1000 1001 1010 1011 1100 1101 1110 100.23 100.90 105.00 66.89 120.00 124.00 133.30 133.30 140.00 150.00 114.99 70.00 75.00 83.31 90.00 100.23 100.90 105.00 100.33 120.00 124.00 133.30 133.30 140.00 150.00 114.99 105.00 112.50 124.96 90.00 33.41 33.63 35.00 33.44 40.00 41.33 44.43 33.32 35.00 37.50 38.33 35.00 37.50 41.65 30.00 3V66 MHz SEL_3V66=0 66.82 67.26 70.00 66.89 64.00* 64.00* 64.00* 66.65 70.00 64.00* 64.00* 70.00 64.00* 64.00* 60.00 SEL_3V66=1 66.82 67.26 70.00 66.89 80.00 82.66 88.86 66.65 70.00 75.00 76.66 70.00 75.00 83.31 60.00 63.33 IOAPIC MHz 16.70 16.81 17.50 16.72 20.00 20.67 22.21 16.66 17.50 18.75 19.16 17.50 18.75 20.83 15.00 15.83 0 1 0 Note 1 Description PWD 0 Bit 3 Bit 1 Bit 0 1111 95.00 95.00 31.67 63.33 0 - Frequency is selected by hardware select, latched inputs 1 - Frequency is selected by Bit 2, 6:4 0 - Normal 1 - Spread spectrum enable 0 - Running 1 - Tristate all outputs Notes: 1. Default at power-up will be for latched logic inputs to define frequency, Bit 2, 6:4 are default to 0000. * These output frequencies are not synchronous to CPUCLK and do not have spread spectrum modulation. 6 ICS9248-78 Preliminary Product Preview Byte 1: Control Register (1 = enable, 0 = disable) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Pin# 27 26 30 PWD X X X 1 1 1 1 1 Description FS3# FS0# FS2# 24MHz (Act/Inact) (Reserved) 48MHz (Act/Inact) (Reserved) SDRAM_F (Act/Inact) Byte 2: Control Register (1 = enable, 0 = disable) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Pin# 31 32 34 35 36 38 39 40 PWD 1 1 1 1 1 Description SDRAM7 (Act/Inact) SDRAM6 (Act/Inact) SDRAM5 (Act/Inact) SDRAM4 (Act/Inact) SDRAM3 (Act/Inact) SDRAM2 (Act/Inact) SDRAM1 (Act/Inact) SDRAM0 (Act/Inact) 1 1 1 Byte 3: Control Register (1 = enable, 0 = disable) Byte 4: Control Register (1 = enable, 0 = disable) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Notes: Pin# 20 19 17 16 15 13 12 11 PWD 1 1 1 1 1 1 1 1 Description PCICLK7 (Act/Inact) PCICLK6 (Act/Inact) PCICLK5 (Act/Inact) PCICLK4 (Act/Inact) PCICLK3 (Act/Inact) PCICLK2 (Act/Inact) PCICLK1 (Act/Inact) PCICLK0 (Act/Inact) Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Pin# 7 8 46 43 44 PWD 0 1 1 X 1 X 1 1 Description (Reserved) 3V66_0 (Act/Inact) 3V66_1 (Act/Inact) SEL_3V66 IOAPIC (Act/Inact0) FS1# CPUCLK1 (Act/Inact) CPUCLK0 (Act/Inact) 1. Inactive means outputs are held LOW and are disabled from switching. These outputs are designed to be configured at power-on and are not expected to be configured during the normal modes of operation. 2. PWD = Power on Default 7 ICS9248-78 Preliminary Product Preview Absolute Maximum Ratings Core Supply Voltage . . . . . . . . . . . . . . . . . . . . . . 4.6 V I/O Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . 3.6V Logic Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . GND 0.5 V to VDD +0.5 V Ambient Operating Temperature . . . . . . . . . . . . 0C to +70C Storage Temperature . . . . . . . . . . . . . . . . . . . . . . 65C to +150C Case Temperature . . . . . . . . . . . . . . . . . . . . . . . . 115C 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/Common Output Parameters TA = 0 - 70C; Supply Voltage VDD = 3.3 V +5%, VDDL=2.5 V+ 5%(unless otherwise stated) PARAMETER Input High Voltage Input Low Voltage Input High Current Input Low Current Input Low Current Operating Supply Current Power Down Supply Current Input frequency Pin Inductance Input Capacitance1 SYMBOL VIH VIL IIH IIL1 IIL2 IDD3.3OP IDD3.3PD Fi Lpin CIN Cout CINX Ttrans Ts TSTAB tPZH,tPZH tPLZ,tPZH CONDITIONS MIN 2 VSS-0.3 -5 -5 -200 MAX UNITS VDD+0.3 V 0.8 V A 5 A 2.0 A -100 60 100 mA 400 14.318 7 Logic Inputs Out put pin capacitance X1 & X2 pins To 1st crossing of target Freq. From 1st crossing to 1% target Freq. From VDD = 3.3 V to 1% target Freq. output enable delay (all outputs) output disable delay (all outputs) 1 1 3 10 10 5 6 45 3 600 A MHz nH pF pF pF ms ms ms ns ns TYP VIN = VDD VIN = 0 V; Inputs with no pull-up resistors VIN = 0 V; Inputs with pull-up resistors CL = 0 pF; Select @ 66M CL = 0 pF; With input address to Vdd or GND VDD = 3.3 V; 27 Transition Time Settling Time Delay 1 1 1 Clk Stabilization1 Guarenteed by design, not 100% tested in production. 8 ICS9248-78 Preliminary Product Preview Electrical Characteristics - CPU TA = 0 - 70C, VDDL = 2.5 V +/-5%; CL = 10 - 20 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Skew Jitter 1 SYMBOL RDSP2B1 RDSN2B1 VOH2B VOL2B IOH2B IOL2B tr2B1 tf2B1 dt2B1 tsk2B1 tjcyc-cyc1 VO = VDD*(0.5) CONDITIONS VO = VDD*(0.5) IOH = -1 mA IOL = 1 mA VOH @MIN= 1.0V , VOH@ MAX= 2.375V VOL @MIN= 1.2V , VOL@ MAX= 0.3V VOL = 0.4 V, VOH = 2.0 V VOH = 0.4 V, VOL = 2.0 V VT = 1.25 V VT = 1.25 V VT = 1.25 V MIN 13.5 13.5 2 -27 27 0.4 0.4 45 TYP MAX UNITS 45 45 0.4 -27 30 1.6 1.6 V V mA mA ns ns ns ps ps 50 55 175 250 Guarenteed by design, not 100% tested in production. Electrical Characteristics - 3V66 TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 10-30 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Skew Jitter 1 SYMBOL RDSP1 RDSN1 VOH1 VOL1 IOH1 IOL1 tr11 tf1 1 1 1 1 1 CONDITIONS VO = VDD*(0.5) MIN 12 TYP MAX UNITS 55 55 0.55 -33 38 1.6 1.6 55 175 500 V V mA mA ns ns % ps ps VO = VDD*(0.5) 12 IOH = -1 mA 2.4 IOL = 1 mA VOH@ MIN = 1.0 V, VOH@ MAX = 3.135 V -33 VOL@ MIN = 1.95 V, VOL@ MAX= 0.4 30 VOL = 0.4 V, VOH = 2.4 V VOH = 2.4 V, VOL = 0.4 V VT = 1.5 V VT = 1.5 V VT = 1.5 V 0.4 0.4 45 dt1 tsk1 tjcyc-cyc Guarenteed by design, not 100% tested in production. 9 ICS9248-78 Preliminary Product Preview Electrical Characteristics - IOAPIC TA = 0 - 70C;VDDL = 2.5 V +/-5%; CL = 10 - 20 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Jitter 1 SYMBOL RDSP4B1 RDSN4B1 VOH4\B VOL4B IOH4B IOL4B tr4B1 tf4B1 dt4B1 tjcyc-cyc VO = VDD*(0.5) CONDITIONS VO = VDD*(0.5) IOH = -5.5 mA IOL = 9.0 mA VOH@ min = 1.4 V, VOH@ MAX = 2.5 V VOL@ MIN = 1.0 V, VOL@ MAX= 0.2 VOL = 0.4 V, VOH = 2.0 V VOH = 2.0 V, VOL = 0.4 V VT = 1.25 V VT = 1.25 V MIN 9 9 2 -36 36 0.4 0.4 45 TYP MAX UNITS 30 30 0.4 -21 31 1.6 1.6 55 500 V V mA mA ns ns % ps Guarenteed by design, not 100% tested in production. Electrical Characteristics - SDRAM TA = 0 - 70C; VDD = VDDL = 3.3 V +/-5%; CL = 20 - 30 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Skew Jitter 1 SYMBOL RDSP3 RDSN3 VOH3 VOL3 IOH3 IOL3 Tr31 Tf3 Dt3 1 1 1 1 1 CONDITIONS VO = VDD*(0.5) VO = VDD*(0.5) IOH = -1 mA IOL = 1 mA VOH @MIN= 2.0 V, VOH@ MAX=3.135 V VOL@ MIN= 1.0 V, VOL@ MAX=0.4 V VOL = 0.4 V, VOH = 2.4 V VOH = 2.4 V, VOL = 0.4 V VT = 1.5 V VT = 1.5 V VT = 1.5 V MIN 10 10 2.4 -54 54 0.4 0.4 45 TYP MAX UNITS 24 24 0.4 -46 53 1.6 1.6 55 250 250 V V mA mA ns ns % ps ps Tsk3 tj cyc-cyc Guarenteed by design, not 100% tested in production. 10 ICS9248-78 Preliminary Product Preview Electrical Characteristics - PCI TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 10-30 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Skew Jitter 1 SYMBOL RDSP1 RDSN1 VOH1 VOL1 IOH1 IOL1 tr11 tf1 1 1 1 1 1 CONDITIONS VO = VDD*(0.5) MIN 12 TYP MAX UNITS 55 55 0.55 -33 38 2 2 55 500 500 V V mA mA ns ns % ps ps VO = VDD*(0.5) 12 IOH = -1 mA 2.4 IOL = 1 mA VOH@ MIN = 1.0 V, VOH@ MAX = 3.135 V -33 VOL@ MIN = 1.95 V, VOL@ MAX= 0.4 30 VOL = 0.4 V, VOH = 2.4 V VOH = 2.4 V, VOL = 0.4 V VT = 1.5 V VT = 1.5 V VT = 1.5 V 0.5 0.5 45 dt1 tsk1 tjcyc-cyc Guarenteed by design, not 100% tested in production. Electrical Characteristics - 48M, REF TA = 0 - 70C; VDD = VDDL = 3.3 V +/-5%; CL = 10 -20 pF (unless otherwise stated) PARAMETER Output Impedance Output Impedance Output High Voltage Output Low Voltage Output High Current Output Low Current Rise Time Fall Time Duty Cycle Jitter Skew 1 SYMBOL RDSP5 RDSN5 VOH5 VOL5 IOH5 IOL5 tr51 tf5 1 1 1 1 CONDITIONS VO = VDD*(0.5) VO = VDD*(0.5) IOH = 1 mA IOL = -1 mA VOH @MIN=1 V, VOH@MAX= 3.135 V VOL@MIN=1.95 V, VOL@MIN=0.4 V VOL = 0.4 V, VOH = 2.4 V VOH = 2.4 V, VOL = 0.4 V VT = 1.5 V VT = 1.5 V; Fixed Clocks VT = 1.5 V; Ref Clocks VT = 1.5 V MIN 20 20 2.4 -29 29 TYP MAX UNITS 60 60 0.4 -23 27 V V mA mA ns ns % ps ps ps 1.8 1.7 45 4 4 55 500 1000 250 dt5 tjcyc-cyc1 tjcyc-cyc1 Tsk Guarenteed by design, not 100% tested in production. 11 ICS9248-78 Preliminary Product Preview Group Offset Waveforms Group Skews at Common Transition Edges: CPU & IOAPIC load (lumped) = 20pf; PCI, SDRAM, 3V66 LOAD (LUMPED) = 30pf. GROUP SYMBOL CONDITIONS MIN CPU @ 1.25V, 3V66 @ 1.5V (Note: 180 CPU (at 66MHz) to 0 SCPU1-3V66 offset between CPU & 3V66 3V66 CPU @ 1.25V, SDRAM @ 1.5V (Note: 180 CPU (at 100MHz) to 0 SCPU2-SDRAM offset between CPU & 66MHz SDRAM 1.5 3V66 to PCI S3V66-PCI 3V66 @ 1.5V, PCI @ 1.5V IOAPIC to PCI SIOAPIC-PCI IOAPIC @ 1.25V, PCI @1.5V 0 TYP MAX UNITS 500 500 2.1 4 500 ps ps ns ps 12 ICS9248-78 Preliminary Product Preview SSOP Package SYMBOL A A1 A2 B C D E e H h L N COMMON DIMENSIONS MIN. NOM. MAX. .095 .101 .110 .008 .012 .016 .088 .090 .092 .008 .010 .0135 .005 .010 See Variations .292 .296 .299 0.025 BSC .400 .406 .410 .010 .013 .016 .024 .032 .040 See Variations 0 5 8 .085 .093 .100 VARIATIONS AC MIN. .620 D NOM. .625 N MAX . .630 48 X Ordering Information ICS9248yF-78 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 (will not correlate with datasheet revision) Device Type (consists of 3 or 4 digit numbers) Prefix ICS, AV = Standard Device 13 PRODUCT PREVIEW documents contain information on new products in the sampling or preproduction phase of development. Characteristic data and other specifications are subject to change without notice. |
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