W83194R-39/-39A 100MHZ 3-DIMM CLOCK 1.0 GENERAL DESCRIPTION The W83194R-39/-39A is a Clock Synthesizer which provides all clocks required for high-speed RISC or CISC microprocessor such as Intel Pentium II. W83194R-39 provides eight different frequency of CPU and PCI clocks and W83194R-39A provides sixteen CPU/PCI frequencies which are externally selectable with smooth transitions. W83194R-39/-39A also provides 13 SDRAM clocks controlled by the none-delay buffer_in pin. The W83194R-39/-39A accepts a 14.318 MHz reference crystal as its input and runs on a 3.3V supply. Spread spectrum built in at O0.5% or O0.25% to reduce EMI. Programmable stopping individual clock outputs and frequency selection through I2C interface. The device meets the Pentium power-up stabilization, which requires CPU and PCI clocks be stable within 2 ms after power-up. It is not recommend to use the dual function pin for the slots(ISA, PCI, CPU, DIMM). The add on cards may have a pull up or pull down. High drive six PCI and thirteen SDRAM CLOCK outputs typically provide greater than 1 V /ns slew rate into 30 pF loads. Two CPU CLOCK outputs typically provide better than 1 V /ns slew rate into 20 pF loads as maintaining 50O 5% duty cycle. The fixed frequency outputs as REF, 24MHz, and 48 MHz provide better than 0.5V /ns slew rate. 2.0 PRODUCT FEATURES * Supports Pentium II CPU with I2C. * 2 CPU clocks (one free-running CPU clock) * 13 SDRAM clocks for 3 DIMs * 6 PCI synchronous clocks * One IOAPIC clock for multiprocessor support * Optional single or mixed supply: (Vddq1=Vddq2 = Vddq3 = Vddq4 = VddL1 =VddL2= 3.3V) or (Vddq1= Vddq2 = Vddq3=Vddq4 = 3.3V, VddL1 = VdqL2 = 2.5V) * < 250ps skew among CPU and SDRAM clocks * < 250ps skew among PCI clocks * < 5ns propagation delay SDRAM from buffer input * Skew from CPU(earlier) to PCI clock -1 to 4ns, center 2.6ns. * Smooth frequency switch with selections from 50 MHz to 133 MHz CPU * I C 2-Wire serial interface and I C read back 2 2 -1- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY * O0.25% or O0.5% spread spectrum function to reduce EMI * Programmable registers to enable/stop each output and select modes (mode as Tri-state or Normal ) * 2ms power up clock stable time * MODE pin for power Management * One 48 MHz for USB & one 24 MHz for super I/O * 48-pin SSOP package 3.0 BLOCK DIAGRAM W83194R-39A W83194R-39 48MHz PLL2 ~ Xin STOP IOAPIC BUFFER IN 2 6 PLL1 MODE* CPU_STOP# Control Logic SDATA* Config. Reg. 2 6 4 PCI Clock Divider STOP CPUCLK1 13 SDRAM(0:12) CPUCLK_F FS(0:3)* 4 STOP LATCH 12 4 POR CPU_STOP# PCI_STOP# SDATA* SDCLK* CPUCLK1 SDRAM12 ~ PCICLK(0:4) 5 -2- STOP Spread Spectrum MODE* PCICLK_F PCI_STOP# SDCLK* STOP LATCH POR BUFFER IN IOAPIC REF(0:1) PLL1 STOP 3 ~ REF(0:1) STOP XTAL OSC CPUCLK_F Spread Spectrum FS(0:2)* Xin Xout 24MHz 1/2 ~ XTAL OSC Xout 48MHz PLL2 24MHz 1/2 PCI Clock Divider STOP SDRAM(0:11) PCICLK(0:4) 5 PCICLK_F Control Logic Config. Reg. Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 4.0 PIN CONFIGURATION Vddq1 PCI_STOP#/REF0 Vss Xin Xout Vddq2 PCICLK_F/MODE* (W83194R-39A ) PCICLK0/FS3* Vss PCICLK1 PCICLK2 PCICLK3 PCICLK4 Vddq2 BUFFER IN Vss SDRAM11 SDRAM10 Vddq3 SDRAM 9 SDRAM 8 Vss SDATA SDCLK 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 48 47 46 45 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 VddL1 IOAPIC REF1/FS2* Vss CPUCLK_F CPUCLK1 VddL2 CPU_STOP# SDRAM12 Vss SDRAM 0 SDRAM 1 Vddq3 SDRAM 2 SDRAM 3 Vss SDRAM 4 SDRAM 5 Vddq3 SDRAM 6 SDRAM 7 Vddq4 48MHz/FS0* 24MHz/FS1* 5.0 PIN DESCRIPTION IN - Input OUT - Output I/O - Bi-directional Pin # - Active Low * - Internal 250k pull-up -3- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 5.1 Crystal I/O SYMBOL PIN I/O Xin 4 IN Xout 5 OUT FUNCTION Crystal input with internal loading capacitors and feedback resistors. Crystal output at 14.318MHz nominally. 5.2 CPU, SDRAM, PCI, IOAPIC Clock Outputs SYMBOL PIN I/O CPUCLK_F 44 OUT Free running CPU clock. Not affected by CPU_STOP# CPUCLK1 43 OUT Low skew (< 250ps) clock outputs for host frequencies such as CPU, Chipset and Cache. Powered by VddL2. Low if CPU_STOP# is low. CPU_STOP# 41 IN IOAPIC 47 OUT High drive buffered output of the crystal, and is powered by VddL1. 17,18,20,21,28 ,29,31,32,34, 35,37,38,40 OUT SDRAM clock outputs. Fanout buffer outputs from BUFFER IN pin.(Controlled by chipset) 7 I/O SDRAM [ 0:12] PCICLK_F/ This asynchronous input halts CPUCLK1,IOAPIC & SDRAM(0:12) at logic "0" level when driven low. *MODE PCICLK0/*FS3 (W83194R-39A) PCICLK [ 0:4 ] SDRAM [ 0: 11 ] Free running PCI clock during normal operation. Latched Input. Mode=1, Pin 2 is REF0; Mode=0, Pin2 is PCI_STOP# 8 I/O Low skew (< 250ps) PCI clock outputs. Latched input for FS3 at initial power up for H/W selecting the output frequency of CPU, SDRAM and PCI clocks. 8,10,11,12,13 OUT 15 IN Inputs to fanout for SDRAM outputs. 17,18,20,21, 28,29,31,32, 34,35,37,38 O Synchronous DRAM DIMs clocks which have the same frequency as CPU clocks (W83194R-39) BUFFER IN FUNCTION -4- Low skew (< 250ps) PCI clock outputs. Synchronous to CPU clocks with 1-48ns skew(CPU early). Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 5.3 I2C Control Interface SYMBOL PIN I/O FUNCTION 2 SDATA 23 I/O Serial data of I C 2-wire control interface with internal pull-up resistor. SDCLK 24 IN Serial clock of I2C 2-wire control interface with internal pull-up resistor. 5.4 Fixed Frequency Outputs SYMBOL REF0 / PCI_STOP# PIN I/O 2 I/O FUNCTION 14.318MHz reference clock. This REF output is the stronger buffer for ISA bus loads. Halt PCICLK(0:4) clocks at logic 0 level, when input low (In mobile mode. MODE=0) REF1 / *FS2 46 I/O 14.318MHz reference clock. Latched input for FS2 at initial power up for H/W selecting the output frequency of CPU, SDRAM and PCI clocks. 24MHz / *FS1 25 I/O 24MHz output clock. Latched input for FS1 at initial power up for H/W selecting the output frequency of CPU, SDRAM and PCI clocks. 48MHz / *FS0 26 I/O 48MHz output for USB during normal operation. Latched input for FS0 at initial power up for H/W selecting the output frequency of CPU, SDRAM and PCI clocks. 5.5 Power Pins SYMBOL PIN FUNCTION Vddq1 1 Power supply for Ref [0:1] crystal and core logic. VddL1 48 Power supply for IOAPIC output, either 2.5V or 3.3V. VddL2 42 Power supply for CPUCLK[0:3], either 2.5V or 3.3V. Vddq2 6, 14 Vddq3 19, 30, 36 Power supply for SDRAM[0:12], and CPU PLL core, nominal 3.3V. Vddq4 27 Power for 24 & 48MHz output buffers and fixed PLL core. Vss Power supply for PCICLK_F, PCICLK[0:4], 3.3V. 3,9,16,22,33,39,45 Circuit Ground. -5- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 6.0 FREQUENCY SELECTION 6.1 Frequency table of W83194R-39 FS2 FS1 FS0 CPU,SDRAM (MHz) PCI (MHz) REF,IOAPIC (MHz) 0 0 0 50 25(CPU/2) 14.318 0 0 1 75 37.5(CPU/2) 14.318 0 1 0 83.3 41.65(CPU/2) 14.318 0 1 1 66.8 33.4(CPU/2) 14.318 1 0 0 103 34.3(CPU/3) 14.318 1 0 1 112 37.33(CPU/3) 14.318 1 1 0 133 33.25(CPU/4) 14.318 1 1 1 100.2 33.3(CPU/3) 14.318 6.2 Frequency table of W83194R-39A FS3=0 CPU,SDRAM (MHz) PCI (MHz) REF,IOAPIC FS2 FS1 FS0 0 0 0 0 0 1 75 37.5(CPU/2) 14.318 0 1 0 83.3 41.65(CPU/2) 14.318 0 1 1 66.8 33.4(CPU/2) 14.318 1 0 0 103 34.3(CPU/3) 14.318 1 0 1 112 37.33(CPU/3) 14.318 1 1 0 133 44.33(CPU/3) 14.318 1 1 1 100.3 33.3(CPU/3) 14.318 CPU,SDRAM (MHz) PCI (MHz) REF,IOAPIC FS3=1 (MHz) 124 41.33(CPU/3) 14.318 FS2 FS1 FS0 (MHz) 0 0 0 120 40.00(CPU/3) 14.318 0 0 1 115 38.33(CPU/3) 14.318 0 1 0 110 36.67(CPU/3) 14.318 0 1 1 105 35.00(CPU/3) 14.318 1 0 0 140 35.00(CPU/4) 14.318 1 0 1 150 37.50(CPU/4) 14.318 1 1 0 124 31.00(CPU/4) 14.318 1 1 1 133 33.25(CPU/4) 14.318 -6- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 7.0 MODE PIN -POWER MANAGEMENT INPUT CONTROL MODE, Pin7 (Latched Input) PIN 2 0 PCI_STOP# (Input) 1 REF0 (Output) -7- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 8.0 FUNTION DESCRIPTION 8.1 POWER MANAGEMENT FUNCTIONS All clocks can be individually enabled or disabled via the 2-wire control interface. On power up, external circuitry should allow 3 ms for the VCO's to stabilize prior to enabling clock outputs to assure correct pulse widths. When MODE=0, pins 15 and 46 are inputs (PCI_STOP#), (CPU_STOP#), when MODE=1, these functions are not available. A particular clock could be enabled as both the 2-wire serial control interface and one of these pins indicate that it should be enable. The W83194R-39/-39Amay be disabled in the low state according to the following table in order to reduce power consumption. All clocks are stopped in the low state, but maintain a valid high period on transitions from running to stop. The CPU and PCI clocks transform between running and stop by waiting for one positive edge on PCICLK_F followed by negative edge on the clock of interest, after which high levels of the output are either enabled or disabled. CPU_STOP# PCI_STOP# CPUCLK1, IOAPIC & SDRAM 0:12 PCI OTHER CLKs XTAL & VCOs 0 0 LOW LOW RUNNING RUNNING 0 1 LOW RUNNING RUNNING RUNNING 1 0 RUNNING LOW RUNNING RUNNING 1 1 RUNNING RUNNING RUNNING RUNNING 8.2 2-WIRE I2C CONTROL INTERFACE The clock generator is a slave I2C component which can be "read back" the data stored in the latches for verification. All proceeding bytes must be sent to change one of the control bytes. The 2wire control interface allows each clock output individually enabled or disabled. On power up, the W83194R-39/-39Ainitializes with default register settings, and then it's optional to use the 2-wire control interface. The SDATA signal only changes when the SDCLK signal is low, and is stable when SDCLK is high during normal data transfer. There are only two exceptions. One is a high-to-low transition on SDATA while SDCLK is high used to indicate the beginning of a data transfer cycle. The other is a low-to-high transition on SDATA while SDCLK is high used to indicate the end of a data transfer cycle. Data is always sent as complete 8-bit bytes followed by an acknowledge generated. Byte writing starts with a "start" condition followed by 7-bit slave address and a write command bit [1101 0010], command code checking [0000 0000], and byte count checking. After successful reception of each byte, an "acknowledge" (low) on the SDATA wire will be generated by the clock 2 chip. Controller can start to write to internal I C registers after the string of data. The sequence order is as follows: -8- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY Bytes sequence order for I2C controller : Clock Address A(6:0) & R/W Ack 8 bits dummy Command code Ack 8 bits dummy Byte count Ack Byte0,1,2... until Stop Ack Byte2, 3, 4... until Stop Set R/W to 1 when "read back", the data sequence is as follows : Clock Address A(6:0) & R/W Ack Byte 0 Ack Byte 1 8.3 SERIAL CONTROL REGISTERS The Pin column lists the affected pin number and the @PowerUp column gives the default state at true power up. "Command Code" byte and "Byte Count" byte must be sent following the acknowledge of the Address Byte. Although the data (bits) in these two bytes are considered "don't care", they must be sent and will be acknowledge. After that, the below described sequence (Register 0, Register 1, Register 2, ....) will be valid and acknowledged. 8.3.1 Register 0: CPU Frequency Select Register (default = 0) Bit @PowerUp Pin 7 0 - Description 0 = O0.25% Spread Spectrum Modulation 1 = O0.5% Spread Spectrum Modulation 6 0 - SSEL2 (for frequency table selection by software via I2C) 5 0 - SSEL1 (for frequency table selection by software via I2C) 4 0 - SSEL0 (for frequency table selection by software via I2C) 3 0 - 0 = Selection by hardware 1 = Selection by software I2C - Bit 6:4 2 0 - SSEL3 (for frequency table selection by software via I2C) 1 0 - 0 = Normal 1 = Spread Spectrum enabled 0 0 - 0 = Running 1 = Tristate all outputs 2 Note : The frequency table selected by software via I C is the same as the hardware setting frequency table. -9- Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY Function Table Function Outputs Description CPU PCI SDRAM REF IOAPIC Tri-State Hi-Z Hi-Z Hi-Z Hi-Z Hi-Z Normal see table see table CPU 14.318 14.318 8.3.2 Register 1 : CPU , 48/24 MHz Clock Register (1 = enable, 0 = Stopped) Bit @PowerUp Pin Description 7 1 - Latched FS2# 6 1 - Reserved 5 1 - Reserved 4 1 - Reserved 3 1 40 2 1 - 1 1 43 CPUCLK1 (Active / Inactive) 0 1 44 CPUCLK_F (Active / Inactive) SDRAM12 (Active / Inactive) Reserved - 10 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 8.3.3 Register 2: PCI Clock Register (1 = enable, 0 = Stopped) Bit @PowerUp Pin Description 7 1 - Reserved 6 1 7 PCICLK_F (Active / Inactive) 5 1 - Reserved 4 1 14 PCICLK4 (Active / Inactive) 3 1 12 PCICLK3 (Active / Inactive) 2 1 11 PCICLK2 (Active / Inactive) 1 1 10 PCICLk1 (Active / Inactive) 0 1 8 PCICLK0 (Active / Inactive) 8.3.4 Register 3: SDRAM Clock Register ( 1 = enable, 0 = Stopped ) Bit @PowerUp Pin Description 7 1 - Reserved 6 1 - Reserved 5 1 26 48MHz (Active / Inactive) 4 1 25 24MHz (Active / Inactive) 3 1 - 2 1 21,20,18,17 SDRAM(8:11) (Active / Inactive) 1 1 32,31,29,28 SDRAM(4:7) (Active / Inactive) 0 1 38,37,35,34 SDRAM(0:3) (Active / Inactive) Reserved - 11 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 8.3.5 Register 4: Reserved Register (1 = enable, 0 = Stopped) Bit @PowerUp Pin Description 7 1 - Reserved 6 1 - Reserved 5 1 - Reserved 4 1 - Reserved 3 1 - Latched FS1# 2 1 - Reserved 1 1 - Reserved 0 1 - Reserved 8.3.6 Register 5: Peripheral Control (1 = enable, 0 = Stopped) Bit @PowerUp Pin Description 7 1 - Reserved 6 1 - Reserved 5 1 - Reserved 4 1 47 3 1 - Reserved 2 1 - Reserved 1 1 46 REF1 (Active / Inactive) 0 1 2 REF0 (Active / Inactive) IOAPIC (Active / Inactive) NOTE: 1.Inactive means outputs are held LOW and are disabled from switching. 2.Latched Frequency Selects(FS#) will be inverted logic load of the input frequency select pin conditions. - 12 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 9.0 SPECIFICATIONS 9.1 ABSOLUTE MAXIMUM RATINGS Stresses greater than those listed in this table may cause permanent damage to the device. Precautions should be taken to avoid application of any voltage higher than the maximum rated voltages to this circuit. Maximum conditions for extended periods may affect reliability. Unused inputs must always be tied to an appropriate logic voltage level (Ground or Vdd). Symbol Parameter Rating Vdd , VIN Voltage on any pin with respect to GND - 0.5 V to + 7.0 V TSTG Storage Temperature - 65C to + 150C TB Ambient Temperature - 55C to + 125C TA Operating Temperature 0C to + 70C 9.2 AC CHARACTERISTICS Vdd = Vddq3 = 3.3V 5 %, Vddq2 = VddL1=VddL2 = 2.375V~2.9V , TA = 0C to +70C Parameter Symbol Output Duty Cycle Min Typ Max Units 45 50 55 % Measured at 1.5V 4 ns 15 pF Load Measured at 1.5V 15 pF Load Measured at 1.5V CPU/SDRAM to PCI Offset tOFF Skew (CPU-CPU), (PCIPCI), (SDRAM-SDRAM) tSKEW 250 ps tCCJ O250 ps tJA 500 ps BWJ 500 KHz 0.4 1.6 ns 15 pF Load on CPU and PCI outputs CPU/SDRAM 1 Test Conditions Cycle to Cycle Jitter CPU/SDRAM Absolute Jitter Jitter Spectrum 20 dB Bandwidth from Center Output Rise (0.4V ~ 2.0V) tTLH & Fall (2.0V ~0.4V) Time tTHL Overshoot/Undershoot Vover 0.7 1.5 V 22 at source of 8 inch PCB run to 15 pF load VRBE 0.7 2.1 V Ring Back must not enter this range. Beyond Power Rails Ring Back Exclusion - 13 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 9.3 DC CHARACTERISTICS Vdd = Vddq3 = 3.3V 5 %, Vddq2 = VddL1=VddL2 = 2.375V~2.9V , TA = 0C to +70C Parameter Symbol Min Typ Max Units 0.8 Vdc Test Conditions Input Low Voltage VIL Input High Voltage VIH Input Low Current IIL -66 A Input High Current IIH 5 A Output Low Voltage VOL 0.4 Vdc All outputs Vdc All outputs using 3.3V power 2.0 Vdc IOL = 4 mA Output High Voltage VOH 2.4 IOH = 4mA Tri-State leakage Current Ioz Dynamic Supply Current Idd3 10 A mA PCI = 33.3 Mhz with load for Vdd + Vddq3 Dynamic Supply Current CPU = 66.6 MHz Idd2 mA Same as above ICPUS3 mA Same as above ICPUS2 mA Same as above IPD3 mA for Vddq2 + Vddq2b CPU Stop Current for Vdd + Vddq3 CPU Stop Current for Vddq2 + Vddq2b PCI Stop Current for Vdd + Vddq3 - 14 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 9.4 BUFFER CHARACTERISTICS 9.4.1 TYPE 1 BUFFER FOR CPU CLOCK Parameter Symbol Min Pull-Up Current Min IOH(min) -27 Pull-Up Current Max IOH(max) Pull-Down Current Min IOL(min) Pull-Down Current Max IOL(max) Rise/Fall Time Min Between 0.4 V and 2.0 V TRF(min) Rise/Fall Time Max Between 0.4 V and 2.0 V TRF(max) Typ Max -27 27 0.4 1.6 Units Test Conditions mA Vout = 1.0 V mA Vout = 2.0V mA Vout = 1.2 V mA Vout = 0.3 V ns 10pF Load ns 20pF Load 9.4.2 TYPE 2 BUFFER FOR IOAPIC Parameter Symbol Pull-Up Current Min IOH(min) Pull-Up Current Max IOH(max) Pull-Down Current Min IOL(min) Pull-Down Current Max IOL(max) Rise/Fall Time Min Between 0.7 V and 1.7 V TRF(min) Rise/Fall Time Max Between 0.7 V and 1.7 V TRF(max) Min Typ Max -29 28 0.4 1.8 - 15 - Units Test Conditions mA Vout = 1.4 V mA Vout = 2.7 V mA Vout = 1.0 V mA Vout = 0.2 V ns 10pF Load ns 20pF Load Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 9.4.3 TYPE 3 BUFFER FOR REF1, 24MHZ, 48MHZ Parameter Symbol Min Pull-Up Current Min IOH(min) -29 Pull-Up Current Max IOH(max) Pull-Down Current Min IOL(min) Pull-Down Current Max IOL(max) Rise/Fall Time Min Between 0.8 V and 2.0 V TRF(min) Rise/Fall Time Max TRF(max) Typ Max Units Test Conditions mA Vout = 1.0 V mA Vout = 3.135V mA Vout = 1.95 V mA Vout = 0.4 V ns 10pF Load 4.0 ns 20pF Load Max Units -23 29 1.0 Between 0.8 V and 2.0 V 9.4.4 TYPE 4 BUFFER FOR SDRAM (0:12) Parameter Symbol Pull-Up Current Min IOH(min) Pull-Up Current Max IOH(max) Pull-Down Current Min IOL(min) Pull-Down Current Max IOL(max) Rise/Fall Time Min Between 0.8 V and 2.0 V TRF(min) Rise/Fall Time Max TRF(max) Min Typ Test Conditions mA Vout = 1.65 V mA Vout = 3.135 V mA Vout = 1.65 V mA Vout = 0.4 V ns 20pF Load 1.3 ns 30pF Load Max Units -46 53 0.5 Between 0.8 V and 2.0 V 9.4.5 TYPE 5 BUFFER FOR PCICLK(0:4,F) Parameter Symbol Min Pull-Up Current Min IOH(min) -33 Pull-Up Current Max IOH(max) Pull-Down Current Min IOL(min) Pull-Down Current Max IOL(max) Rise/Fall Time Min Between 0.8 V and 2.0 V TRF(min) Rise/Fall Time Max TRF(max) Typ -33 30 38 0.5 2.0 Test Conditions mA Vout = 1.0 V mA Vout = 3.135 V mA Vout = 1.95 V mA Vout = 0.4 V ns 15pF Load ns 30pF Load Between 0.8 V and 2.0 V - 16 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 10.0 POWER MANAGEMENT TIMING 10.1 CPU_STOP# Timing Diagram CPUCLK (Internal) 1 2 3 4 1 2 3 4 PCICLK (Internal) PCICLK_F CPU_STOP# CPUCLK[0:3] SDRAM For synchronous Chipset, CPU_STOP# pin is an asynchronous " active low " input pin used to stop the CPU clocks for low power operation. This pin is asserted synchronously by the external control logic at the rising edge of free running PCI clock(PCICLK_F). All other clocks will continue to run while the CPU clocks are stopped. The CPU clocks will always be stopped in a low state and resume output with full pulse width. In this case, CPU "clocks on latency" is less than 4 CPU clocks and "clocks off latency" is less then 4 CPU clocks. 10.2 PCI_STOP# Timing Diagram CPUCLK (Internal) PCICLK 2 1 1 2 (Internal) PCICLK_F PCI_STOP# PCICLK[0:5] For synchronous Chipset, PCI_STOP# pin is an asynchronous "active low" input pin used to stop the PCICLK [0:4] for low power operation. This pin is asserted synchronously by the external control logic at the rising edge of free running PCI clock(PCICLK_F). All other clocks will continue to run while the PCI clocks are stopped. The PCI clocks will always be stopped in a low state and resume output with full pulse width. In this case, PCI "clocks on latency" is less than 2 PCI clocks and "clocks off latency" is less then 2 PCI clocks. - 17 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 11.0 OPERATION OF DUAL FUCTION PINS Pins 2, 7, 8, 25, and 26 are dual function pins and are used for selecting different functions in this device (see Pin description). During power up, these pins are in input mode (see Fig1), therefore, and are considered input select pins. When Vdd reaches 2.5V, the logic level that is present on these pins are latched into their appropriate internal registers. Once the correct information are properly latched, these pins will change into output pins and will be pulled low by default. At the end of the power up timer (within 3 ms) outputs starts to toggle at the specified frequency. 2.5V #7 PCICLK_F/MODE #46 REF1/FS2 #25 24/FS1 #26 48/FS0 Output tri-state Vdd Output pull-low Within 3ms Input All other clocks Output Output tri-state Output pull-low Each of these pins are a large pull-up resistor ( 250 k @3.3V ) inside. The default state will be logic 1, but the internal pull-up resistor may be too large when long traces or heavy load appear on these dual function pins. Under these conditions, an external 10 k resistor is recommended to be connected to Vdd if logic 1 is expected. Otherwise, the direct connection to ground if a logic 0 is desired. The 10 k resistor should be place before the serious terminating resistor. Note that these logic will only be latched at initial power on. If optional EMI reducing capacitor are needed, they should be placed as close to the series terminating resistor as possible and after the series terminating resistor. These capacitor has typical values ranging from 4.7pF to 22pF. - 18 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY Vdd 10k Series Terminating Resistor Device Pin Clock Trace EMI Reducing Cap 10k Optional Ground Ground Programming Header Vdd Pad Ground Pad 10k Series Terminating Resistor Device Pin Clock Trace EMI Reducing Cap Optional Ground - 19 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 13.0 ORDERING INFORMATION Part Number Package Type Production Flow W83194R-39/-39A 48 PIN SSOP Commercial, 0C to +70C 14.0 HOW TO READ THE TOP MARKING W83194R-39 28051234 814GBB W83194R-39A 28051234 814GBB 1st line: Winbond logo and the type number: W83194R-39/-39A 2nd line: Tracking code 2 8051234 2: wafers manufactured in Winbond FAB 2 8051234: wafer production series lot number 3rd line: Tracking code 814 G B B 814: packages made in '98, week 14 G: assembly house ID; A means ASE, S means SPIL, G means GR BB: IC revision All the trade marks of products and companies mentioned in this data sheet belong to their respective owners. - 20 - Publication Release Date: May 1998 Revision 0.20 W83194R-39/-39A PRELIMINARY 15.0 PACKAGE DRAWING AND DIMENSIONS Headquarters Winbond Electronics (H.K.) Ltd. No. 4, Creation Rd. III Science-Based Industrial Park Hsinchu, Taiwan TEL: 886-35-770066 FAX: 886-35-789467 www: http://www.winbond.com.tw/ Rm. 803, World Trade Square, Tower II 123 Hoi Bun Rd., Kwun Tong Kowloon, Hong Kong TEL: 852-27516023-7 FAX: 852-27552064 Winbond Electronics (North America) Corp. 2730 Orchard Parkway San Jose, CA 95134 U.S.A. TEL: 1-408-9436666 FAX: 1-408-9436668 Taipei Office 11F, No. 115, Sec. 3, Min-Sheng East Rd. Taipei, Taiwan TEL: 886-2-7190505 FAX: 886-2-7197502 TLX: 16485 WINTPE Please note that all data and specifications are subject to change without notice. All the trade marks of products and companies mentioned in this data sheet belong to their respective owners. These products are not designed for use in life support appliances, devices, or systems where malfunction of these products can reasonably be expected to result in personal injury. Winbond customers using or selling these products for use in such applications do so at their own risk and agree to fully indemnify Winbond for any damages resulting from such improper use or sale. - 21 - Publication Release Date: May 1998 Revision 0.20