View ICS94236_409984.PDF datasheet online --- IC-ON-LINE

Datasheet File OCR Text:

Integrated Circuit Systems, Inc.
ICS94236
Programmable System Clock Chip for AMD - K7TM processor
Recommended Application: VIA KX/KT133 style chipset Output Features: * 1 - Differential pair open drain CPU clocks * 1 - CPU clock @ 3.3V * 13 - SDRAM @ 3.3V * 6 - PCI @3.3V, * 1 - 48MHz, @3.3V fixed. * 1 - 24/48MHz @ 3.3V * 2 - REF @3.3V, 14.318MHz. Features: * Programmable ouput frequency. * Programmable ouput rise/fall time. * Programmable PCI_F and PCICLK skew. * Spread spectrum for EMI control typically by 7dB to 8dB, with programmable spread percentage. * Watchdog timer technology to reset system if over-clocking causes malfunction. * Uses external 14.318MHz crystal. * FS pins for frequency select
Pin Configuration
VDDREF REF0 GND X1 X2 VDDPCI 1 FS4/PCICLK_F **FS3/PCICLK0 GND *SEL24_48#/PCICLK1 PCICLK2 PCICLK3 PCICLK4 VDDPCI BUFFER IN GND SDRAM11 SDRAM10 VDDSDR SDRAM9 SDRAM8 GND SDATA SCLK 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 REF1/FS2** GND CPUCLK GND CPUCLKC0 CPUCLKT0 VDDCPU PD#* SDRAM_OUT GND SDRAM0 SDRAM1 VDDSDR SDRAM2 SDRAM3 GND SDRAM4 SDRAM5 VDDSDR SDRAM6 SDRAM7 VDD48 48MHz/FS0* 24/48MHz/FS1**
48-Pin 300mil SSOP
* ** 1 Internal Pull-up Resistor of 120K to VDD. Internal Pull-down Resistor of 120K to GND. Internal Pull-down Resistor of 60K to GND.
Block Diagram
PLL2 /2 X1 X2 XTAL OSC PLL1 Spread Spectrum 48MHz 24_48MHz
Functionality
FS 3 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 FS 2 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 ( M H z) 95.00 100.00 102.00 105.00 110.00 113.00 115.00 120.00 1 3 3 . 33 135.00 137.00 139.00 141.00 143.00 145.00 150.00 P C IC L K (MHz) 31.67 33.33 34.00 35.00 36.67 37.67 38.33 40.00 33.33 33.75 34.25 34.75 35.25 35.75 36.25 37.50
REF (1:0) CPUCLK
CPU DIVDER
CPUCLKC0 CPUCLKT0
SEL24_48# SDATA SCLK FS (4:0) PD#
Control Logic Config. Reg.
PCI DIVDER
PCICLK (4:0) PCICLK_F
SDRAM DRIVER
SDRAM (11:0) SDRAM_OUT
BUFFER IN
* 16 additional frequency selectables via FS4, refer to page5 for frequency table.
0451A--01/10/03
ICS94236
General Description
The ICS94236 is a main clock synthesizer chip for AMD-K7 based systems with VIA style chipset. This provides all clocks required for such a system. The ICS94236 belongs to ICS new generation of programmable system clock generators. It employs serial programming I2C interface as a vehicle for changing output functions, changing output frequency, configuring output strength, configuring output to output skew, changing spread spectrum amount, changing group divider ratio and dis/ enabling individual clocks. This device also has ICS propriety 'Watchdog Timer' technology which will reset the frequency to a safe setting if the system become unstable from over clocking.
Pin Descriptions
P I N N U MB E R 1 2 3,9,16,22, 33,39,45, 47 4 5 6,14 7 FS4 2 8 10 11, 12, 13 15 17, 18, 20, 21, 28, 29, 31, 32, 34, 35,37,38 19,30,36 23 24 25 26 27 40 41 42 43 44 46 48 FS3 PCICLK0 SEL24_48#1, 2 PCICLK1 PCICLK(2:4) BUFFER IN SDRAM (11:0) VDDSDR SDATA SCLK 24_48MHz FS1 2 48MHz FS0 2 VDD48 SDRAM_OUT PD#1, 2 VDDCPU CPUCLKT0 CPUCLKC0 CPUCLK REF1 FS22
2
PIN NAME V DDR E F R E F0 GND X1 X2 V DDPC I PCICLK_F
TY P E DE SCRIPT ION P WR R EF, XTA L p ow er su pp ly, no minal 3.3 V 1 4.3 1 8 Mh z r ef er en ce clo ck.Th is REF ou tpu t is th e STRONGER O UT bu f f e r f o r I S A B U S l oa d s P WR IN OUT P WR O UT IN IN O UT IN O UT O UT IN O UT PWR IN IN O UT IN O UT IN PWR O UT IN PWR O UT O UT O UT OUT IN Gro u nd Cr ys tal in pu t, h as in tern al lo ad cap (3 6 pF) an d f eedb ack r e s i s t o r f ro m X 2 Cr ys tal o utp ut, no minally 1 4.3 1 8MH z. Has in ter n al load c a p ( 3 6 pF ) S up ply f o r PC IC LK_F an d PC IC LK, no min al 3 .3V Free running PCI clock not affected by PCI_STOP# for power management. Pin 17, pin 18 function select pin, 1=Desktop Mode, 0=Mobile Mode. Latched Input. Frequency select pin. Latched Input. Internal Pull-down to GND PCI clock output Logic input to select 24 or 48MHz for pin 25 output PCI clock output. PCI clock outputs. Input to Fanout Buffers for SDRAM outputs. SDRAM clock outputs, Fanout Buffer outputs from BUFFER IN pin (controlled by chipset). Supply for SDRAM nominal 3.3V. Data input for I2C serial input, 5V tolerant input Clock input of I2C input, 5V tolerant input 24MHz/48MHz clock output Frequency select pin. Latched Input. 48MHz output clock Frequency select pin. Latched Input Power for 24 & 48MHz output buffers and fixed PLL core. Reference clock for SDRAM zero delay buffer Powers down chip, active low Supply for CPU clock 3.3V "True" clocks of differential pair CPU outputs. These open drain outputs need an external 1.5V pull-up. "Complementory" clocks of differential pair CPU outputs. These open drain outputs need an external 1.5V pull-up. 3.3V CPU clock output powered by VDDCPU 14.318 MHz reference clock. Frequency select pin. Latched Input
Notes: 1: Internal Pull-up Resistor of 120K to 3.3V on indicated inputs 2: Bidirectional input/output pins, input logic levels are latched at internal power-on-reset. Use 10Kohm resistor to program logic Hi to VDD or GND for logic low.
0451A--01/10/03
2
ICS94236
General I2C serial interface information for the ICS94236 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 Byte 0 through Byte 20 (see Note) * 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 Byte 0 through byte 8 (default) ICS clock sends Byte 0 through byte X (if X(H) was written to byte 8). * 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 /Receive r)
ACK
Dummy Byte Count
ACK
Byte 0
ACK
Byte 1
ACK
Byte 2
ACK
Byte 3
ACK
Byte 4
ACK
Byte 5 Byte 6
ACK If 7H has been written to B8 ACK
Byte 18 Byte 19 Byte 20 Stop Bit
If 12H has been written to B8 ACK If 13H has been written to B8 ACK If 14H has been written to B8 ACK Stop Bit
*See notes on the following page.
0451A--01/10/03
3
ICS94236
Brief I2C registers description for ICS94236 Programmable System Frequency Generator
Register Name Functionality & Frequency Select Register Output Control Registers Byte 0 Description Output frequency, hardware / I C frequency select, spread spectrum & output enable control register. Active / inactive output control registers/latch inputs read back. Byte 11 bit[7:4] is ICS vendor id - 1001. Other bits in this register designate device revision ID of this part. Writing to this register will configure byte count and how many byte will be read back. Do not write 00 H to this byte. Writing to this register will configure the number of seconds for the watchdog timer to reset. Watchdog enable, watchdog status and programmable 'safe' frequency' can be configured in this register. This bit select whether the output frequency is control by hardware/byte 0 configurations or byte 11&12 programming. These registers control the dividers ratio into the phase detector and thus control the VCO output frequency. These registers control the spread percentage amount. Increment or decrement the group skew amount as compared to the initial skew. These registers will control the output rise and fall time.
2
PWD Default See individual byte description See individual byte description See individual byte description
1-6
Vendor ID & Revision ID Registers
7
Byte Count Read Back Register
8
08H
Watchdog Timer Count Register
9
10H
Watchdog Control Registers 10 Bit [6:0]
000,0000
VCO Control Selection Bit
10 Bit [7]
0
VCO Frequency Control Registers Spread Spectrum Control Registers Group Skews Control Registers Output Rise/Fall Time Select Registers
11-12
Depended on hardware/byte 0 configuration Depended on hardware/byte 0 configuration See individual byte description See individual byte description
13-14
15-16 17-20
Notes:
1.
2. 3. 4. 5. 6.
7.
The ICS clock generator is a slave/receiver, I2C component. It can read back the data stored in the latches for verification. Readback will support standard SMBUS controller protocol. The number of bytes to readback is defined by writing to byte 8. When writing to byte 11 - 12, and byte 13 - 14, they must be written as a set. If for example, only byte 14 is written but not 15, neither byte 14 or 15 will load into the receiver. 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.
0451A--01/10/03
4
ICS94236
Serial Configuration Command Bitmap
Byte0: Functionality and Frequency Select Register (default = 0)
Bit
Description Bit2 Bit7 Bit6 Bit5 Bit4 CPUCLK PCICLK Spread % FS4 FS3 FS2 FS1 FS0 MH z MHz 0 0 0 0 0 95.00 31.67 0.45% Center Spread 0 0 0 0 1 100.00 33.33 0.45% Center Spread 0 0 0 1 0 102.00 34.00 0.45% Center Spread 0 0 0 1 1 105.00 35.00 0.45% Center Spread 0 0 1 0 0 110.00 36.67 0.45% Center Spread 0 0 1 0 1 113.00 37.67 0.45% Center Spread 0 0 1 1 0 115.00 38.33 0.45% Center Spread 0 0 1 1 1 120.00 40.00 0.45% Center Spread 0 1 0 0 0 133.33 33.33 0.45% Center Spread 0 1 0 0 1 135.00 33.75 0.45% Center Spread 0 1 0 1 0 137.00 34.25 0.45% Center Spread 0 1 0 1 1 139.00 34.75 0.45% Center Spread 0 1 1 0 0 141.00 35.25 0.45% Center Spread 0 1 1 0 1 143.00 35.75 0.45% Center Spread 0 1 1 1 0 145.00 36.25 0.45% Center Spread 0 1 1 1 1 150.00 37.50 0.45% Center Spread 1 0 0 0 0 100.90 33.63 0.45% Center Spread 1 0 0 0 1 100.00 33.33 0 to - 0.7% spread 1 0 0 1 0 103.00 34.33 0.45% Center Spread 1 0 0 1 1 107.00 35.67 0.45% Center Spread 1 0 1 0 0 117.00 39.00 0.45% Center Spread 1 0 1 0 1 120.00 30.00 0.45% Center Spread 1 0 1 1 0 123.00 30.75 0.45% Center Spread 1 0 1 1 1 125.00 31.25 0.45% Center Spread 1 1 0 0 0 133.33 33.33 0 to - 0.7% spread 1 1 0 0 1 133.90 33.48 0.45% Center Spread 1 1 0 1 0 147.00 36.75 0.45% Center Spread 1 1 0 1 1 151.00 37.75 0.45% Center Spread 1 1 1 0 0 153.00 38.25 0.45% Center Spread 1 1 1 0 1 155.00 38.75 0.45% Center Spread 1 1 1 1 0 160.00 40.00 0.45% Center Spread 1 1 1 1 1 200.00 50.00 0.45% Center Spread 0-Frequency is selected by hardware select, latched inputs 1- Frequency is selected by Bit 2,7:4 0- Normal 1- Spread spectrum enable 0- Running 1- Tristate all outputs
P WD
Bit (2,7:4)
Note 1
Bit 3 Bit 1 Bit 0
0 1 0
Note: Default at power-up will be for latched logic inputs to define frequency, as displayed by Bit 3.
0451A--01/10/03
5
ICS94236
Byte 1: CPU, Active/Inactive Register (1= enable, 0 = disable)
BIT
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
Byte 2: PCI, Active/Inactive Register (1= enable, 0 = disable)
PI N #
46 40 43,44 -
PWD
X 1 1 X 1 X 1 1 FS2#
DE S CR I P TI ON
CPUCLK (Reserved) FS3# SDRAM_OUT (SEL24_48#)# CPUCLK0 enable (both differential pair. "True" and Complimentary") (Reserved)*
BI T
Bi t 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bi t 1 Bit 0
PI N#
7 13 12 11 10 8
P WD
X 1 1 1 1 1 1 1 FS0#
DE S C RI P T IO N
PCICLK_F (Reserved) PCICLK4 PCICLK3 PCICLK2 PCICLK1 PCICLK0
Note:
* It is recommended to drive this bit to 0. Byte 3: SDRAM, Active/Inactive Register (1= enable, 0 = disable) Byte 4: SDRAM , Active/Inactive Register (1= enable, 0 = disable)
B IT
Bit 7 Bi t 6 Bit 5 Bi t 4 Bit 3 Bi t 2 Bit 1 Bi t 0
P IN#
26 25 17 18 20 21
P WD
1 1 1 1 1 1 1 1
DE S CR IP T I O N
(Reserved) (Reserved) 48MHz 24_48MHz SD R A M 1 1 SD R A M 1 0 SD R A M 9 SD R A M 8
B IT
Bit 7 Bi t 6 Bit 5 Bi t 4 Bi t 3 Bi t 2 Bit 1 Bi t 0
PI N# PW D
28 29 31 32 34 35 37 38 1 1 1 1 1 1 1 1
DE SCRI PTI ON
S DRAM 7 S DRAM 6 S DRAM 5 S DRAM 4 S DRAM 3 S DRAM 2 S DRAM 1 S DRAM 0
Byte 5: Peripheral , Active/Inactive Register (1= enable, 0 = disable)
Byte 6: Peripheral , Active/Inactive Register (1= enable, 0 = disable)
BI T
Bi t 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bi t 1 Bit 0 Notes:
PI N# PW D
48 2 1 1 1 X X 1 1 1
DE S CR IP T I ON
(Reserved) (Reserved) (Reserved) Mode FS1# (Reserved) REF 1 REF0
B IT B it7 B i t6 B it 5 B i t4 B it 3 B i t2 B it1 B i t0
P IN# -
PWD 0 0 0 0 0 1 1 0
D ESCRI PTI ON Res erved (Not e) Res erved (Not e) Res erved (Not e) Res erved (Not e) Res erved (Not e) Res erved (Not e) Res erved (Not e) Res erved (Not e)
Note: Don't write into this register, writing into this register can cause malfunction
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.
0451A--01/10/03
6
ICS94236
Byte 7: Vendor ID and Revision ID Register
Byte 8: Byte Count and Read Back Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 0 0 1 X X X X X
Description Vendor ID Vendor ID Vendor ID Revision ID Revision ID Revision ID Revision ID Revision ID
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 0 0 0 0 1 0 0 0
Description Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved
Byte 9: Watchdog Timer Count Register
Byte 10: VCO Control Selection Bit & Watchdog Timer Control Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 0 0 0 0 0 0 0 0
Description The decimal representation of these 8 bits correspond to 290ms or 1ms the watchdog timer will wait before it goes to alarm mode and reset the frequency to the safe setting. Default at power up is 290ms.
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 0 0 0 1 0 0 0 0
Description 0=Hw/B0 freq / 1=B11 & 12 freq WD Enable 0=disable / 1=enable WD Status 0=normal / 1=alarm WD Safe Frequency, Byte 0 bit 2 WD Safe Frequency, FS3 WD Safe Frequency, FS2 WD Safe Frequency, FS1 WD Safe Frequency, FS0
Note: FS values in bit [0:4] will correspond to Byte 0 FS values. Default safe frequency is same as 00000 entry in byte0.
Byte 11: VCO Frequency Control Register
Byte 12: VCO Frequency Control Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description VCO Divider Bit0 REF Divider Bit6 REF Divider Bit5 REF Divider Bit4 REF Divider Bit3 REF Divider Bit2 REF Divider Bit1 REF Divider Bit0
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description VCO Divider Bit8 VCO Divider Bit7 VCO Divider Bit6 VCO Divider Bit5 VCO Divider Bit4 VCO Divider Bit3 VCO Divider Bit2 VCO Divider Bit1
Note: The decimal representation of these 7 bits (Byte 11 [6:0]) + 2 is equal to the REF divider value .
Notes: 1. PWD = Power on Default
Note: The decimal representation of these 9 bits (Byte 12 bit [7:0] & Byte 11 bit [7] ) + 8 is equal to the VCO divider value. For example if VCO divider value of 36 is desired, user need to program 36 - 8 = 28, namely, 0, 00011100 into byte 12 bit & byte 11 bit 7.
0451A--01/10/03
7
ICS94236
Byte 13: Spread Sectrum Control Register
Byte 14:
Spread Sectrum Control Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description Spread Spectrum Bit7 Spread Spectrum Bit6 Spread Spectrum Bit5 Spread Spectrum Bit4 Spread Spectrum Bit3 Spread Spectrum Bit2 Spread Spectrum Bit1 Spread Spectrum Bit0
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description Reserved Reserved Reserved Spread Spectrum Bit12 Spread Spectrum Bit11 Spread Spectrum Bit10 Spread Spectrum Bi 9 Spread Spectrum Bit8
Note: Please utilize software utility provided by ICS Application Engineering to configure spread spectrum. Incorrect spread percentage may cause system failure.
Note: Please utilize software utility provided by ICS Application Engineering to configure spread spectrum. Incorrect spread percentage may cause system failure.
Byte 15: Output Skew Control
Byte 16: Output Skew Control
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD Description 0 0 PCI_F Skew Control 0 0 0 0 PCICLK [0:4] Skew Control 0 0
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved
Byte 17: Output Rise/Fall Time Select Register
Byte 18: Output Rise/Fall Time Select Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 1 1 X 0 1 0 1 0
Description CPUCLKT0 CPUCLKC0 Reserved CPUCLK SDRAM_OUT: Slew Rate Control SDRAM [0:11] Slew Rate Control
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD 1 0 1 0 1 0 1 0
Description PCI [0:4]: Slew Rate Control PCI_F Slew Rate Control 48MHz: Slew Rate Control 24MHz: Slew Rate Control
Notes: 1. PWD = Power on Default 2. The power on default for byte 13-20 depends on the harware (latch inputs FS[0:4]) or I2C (Byte 0 bit [1:7]) setting. Be sure to read back and re-write the values of these 8 registers when VCO frequency change is desired for the first pass. 3. If Byte 8 bit 7 is driven to "1" meaning programming is intended, Byte 21-24 will lose their default power up value.
0451A--01/10/03
8
ICS94236
Byte 19: Reserved Register
Byte 20: Reserved Register
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved
Bit Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
PWD X X X X X X X X
Description Reserved Reserved Reserved Reserved Reserved Reserved Reserved Reserved
Note: Byte 19 and 20 are reserved registers, these VCO Programming Constrains VCO Frequency ...................... 150MHz to 500MHz VCO Divider Range ................ 8 to 519 REF Divider Range ................. 2 to 129 Phase Detector Stability .......... 0.3536 to 1.4142 Useful Formula VCO Frequency = 14.31818 x VCO/REF divider value Phase Detector Stabiliy = 14.038 x (VCO divider value)-0.5 To program the VCO frequency for over-clocking. 0. Before trying to program our clock manually, consider using ICS provided software utilities for easy programming. 1. Select the frequency you want to over-clock from with the desire gear ratio (i.e. CPU:SDRAM:3V66:PCI ratio) by writing to byte 0, or using initial hardware power up frequency. 2. Write 0001, 1001 (19H) to byte 8 for readback of 21 bytes (byte 0-20). 3. Read back byte 11-20 and copy values in these registers. 4. Re-initialize the write sequence. 5. Write a '1' to byte 9 bit 7 and write to byte 11 & 12 with the desired VCO & REF divider values. 6. Write to byte 13 to 20 with the values you copy from step 3. This maintains the output spread, skew and slew rate. 7. The above procedure is only needed when changing the VCO for the 1st pass. If VCO frequency needed to be changed again, user only needs to write to byte 11 and 12 unless the system is to reboot. Note: 1. User needs to ensure step 3 & 7 is carried out. Systems with wrong spread percentage and/or group to group skew relation programmed into bytes 13-16 could be unstable. Step 3 & 7 assure the correct spread and skew relationship. 2. If VCO, REF divider values or phase detector stability are out of range, the device may fail to function correctly. 3. Follow min and max VCO frequency range provided. Internal PLL could be unstable if VCO frequency is too fast or too slow. Use 14.31818MHz x VCO/REF divider values to calculate the VCO frequency (MHz). 4. ICS recommends users, to utilize the software utility provided by ICS Application Engineering to program the VCO frequency. 5. Spread percent needs to be calculated based on VCO frequency, spread modulation frequency and spreadamount desired. See Application note for software support.
0451A--01/10/03
are unused registers writing to these registers will not affect device performance or functinality.
9
ICS94236
Absolute Maximum Ratings
Supply Voltage . . . . . . . . . . . . . . . . . . . . . . . . . 5.5V 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 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 Volt age VDD = 3.3 V +/-5% (unless otherwise stated) PARAMETER SYMBOL CONDITIONS VIH Input High Voltage VIL Input Low Voltage IIH VIN = VDD Input High Current VIN=0 V; Inputs with no pull-up IIL1 Input Low Current resistors Input Low Current Operating Supply Current Power Down Input frequency Input Capacitance1
1
MIN 2 VSS - 0.3 -5 -200
TYP
MAX VDD + 0.3 0.8 5
UNITS V V A uA uA
IIL2 IDD3.3OP66 IDD3.3OP100 IDD3.3OP133 PD Fi CIN CINX TSTAB tCPU-PCI
VIN=0 V; Inputs with pull-up resistors CL=0 pF; Select@ 66MHz CL=0 pF; Select@ 100MHz CL=0 pF; Select@ 133MHz VDD = 3.3 V; Logic Inputs X1 & X2 pins From VDD= 3.3 V to 1% target Freq. VT = 50% to 1.5V
12 27 1
87 91 104 3.25 14.318
180 5 16 5 45 3 4
mA mA MHz pF pF ms ns
1
Clk Stabilization 1 Skew Guaranteed by design, not 100% tested in production.
2.8
0451A--01/10/03
10
ICS94236
Electrical Characteristics - REF(0:1)
TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 20 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS VOH5 IOH = -12 mA Output High Voltage VOL5 IOL = 9 mA Output Low Voltage IOH5 VOH = 2.0 V Output High Current IOL5 VOL = 0.8 V Output Low Current 1 tr5 VOL = 0.4 V, VOH = 2.4 V Rise Time 1 tf5 VOH = 2.4 V, VOL = 0.4 V Fall Time 1 dt5 VT = 1.5V Duty Cycle 1 tjcyc-cyc2B VT = 1.5V Jitter, Cycle-to-cycle
1
MIN 2.4
TYP
MAX 0.4 -22
16 1.2 1.5 54.1 1007 4 4 55 1100
45
UNITS V V mA mA ns ns % ps
Guaranteed by design, not 100% tested in production.
Electrical Characteristics - CPUCLK (Open Drain)
TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 20 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS Z0 VO = VX Output Impedance VOH2B Termination to Vpull-up(external) Output High Voltage VOL2B Termination to Vpull-up(external) Output Low Voltage IOL2B VOL = 0.3 V Output Low Current 1 tr2B VOL = 0.3 V, VOH = 1.2 V Rise Time 1 tf2B VOH = 1.2 V, VOL = 0.3 V Fall Time Differential voltage-AC Differential voltage-DC
1
MIN 1 18
TYP
MAX 1.2 0.4 0.9 0.9
UNITS V V mA ns ns V V
VDIF VDIF
Note 2 Note 2
0.4 0.2
1
Vpu +0.6 Vpu +0.6
VX Note 3 550 1100 mV Differential Crossover 1 dt2B VT = 50% 45 51 55 % Duty Cycle 1 tsk2B VT = 50% 163 200 ps Skew 1 tjcyc-cyc2B VT = VX 201 250 ps Jitter, Cycle-to-cycle 1 tjabs2B VT = 50% -250 250 ps Jitter, Absolute 1 - Guaranteed by design, not 100% tested in production. 2 - VDIF specifies the minimum input differential voltage (VTR-VCP) required for switching, where VTR is the "true" input level and VCP is the "complement" input level 3 - Vpullup(external)=1.5V, Min=Vpullup(External)/2-150mV, Max=Vpullup(external)/2+150mV
0451A--01/10/03
11
ICS94236
Electrical Characteristics - CPUCLK (Push-Pull)
TA = 0 - 70C; VDDL = 2.5 V +/-5%; CL = 10-20 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS 1 RDSP2B VO = VDD*0.5 Output Impedance 1 RDSN2B VO = VDD*0.5 Output Impedance VOH2B IOH = -12mA Output High Voltage VOL2B IOL = 12mA Output Low Voltage IOH2B VOH = 1.7 V Output High Current IOL2B VOL = 0.7 V Output Low Current 1 tr2B VOL = 0.4 V, VOH = 2.0 V Rise Time 1 VOH = 2.0 V, VOL = 0.4 V Fall Time tf2B 1 dt2B VT = 1.25V Duty Cycle tsk2B VT = 1.25V Skew Window tjcyc-cyc2B VT = 1.25V Jitter, Cycle-to-cycle1 1 - Guaranteed by design, not 100% tested in production. MIN 10 10 2 TYP MAX 20 20 0.4 -19 19 0.4 0.4 45 1.2 1.1 46.9 142 177 1.6 1.6 55 375 250 UNITS
V V mA mA ns ns % ps ps
Electrical Characteristics - PCICLK_F, PCICLK(0:4)
TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 20 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS VOH5 IOH = -11 mA Output High Voltage VOL5 IOL = 9.4 mA Output Low Voltage IOH5 VOH = 2.0 V Output High Current IOL5 VOL = 0.8 V Output Low Current 1 tr5 VOL = 0.4 V, VOH = 2.4 V Rise Time 1 tf5 VOH = 2.4 V, VOL = 0.4 V Fall Time 1 dt5 VT = 1.5V Duty Cycle 1 1 VT = 1.5V Tsk Skew (window) 1 tjcyc-cyc2B VT = 1.5V Jitter, Cycle-to-cycle
1
MIN 2.6
TYP
MAX 0.4 -16
19 1.8 2 51.7 108 223 2.3 2.3 55 500 500
45
UNITS V V mA mA ns ns % ps ps
Guaranteed by design, not 100% tested in production.
0451A--01/10/03
12
ICS94236
Electrical Characteristics - SDRAM
TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 20-30 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS 1 RDSP3B VO = VDD*0.5 Output Impedance VOH3 IOH = -18mA Output High Voltage VOL3 IOL = 9.4mA Output Low Voltage IOH3 VOH = 2.0 V Output High Current IOL3 VOL = 0.8 V Output Low Current 1 tr3 VOL = 0.4 V, VOH = 2.4 V Rise Time 1 tf3 VOH = 2.4 V, VOL = 0.4 V Fall Time 1 dt3 VT = 1.5V Duty Cycle (0:11) tsk3 VT = 1.5V Skew Window (0:12) tsk3 VT = 1.5V Skew Window 1 tjcyc-cyc3 VT = 1.5V Jitter, Cycle-to-cycle 1 - Guaranteed by design, not 100% tested in production. MIN 10 2.4 TYP MAX 24 0.4 -46 19 0.8 0.8 48.5 192 290 173 1.6 1.6 55 250 500 250 UNITS V V mA mA ns ns % pS pS pS
45
Electrical Characteristics - 24MHz,48MHz
TA = 0 - 70C; VDD = 3.3 V +/-5%; CL = 20 pF (unless otherwise stated) PARAMETER SYMBOL CONDITIONS VOH5 IOH = -16 mA Output High Voltage VOL5 IOL = 9 mA Output Low Voltage IOH5 VOH = 2.0 V Output High Current IOL5 VOL = 0.8 V Output Low Current 1 tr5 VOL = 0.4 V, VOH = 2.4 V Rise Time tf5 VOH = 2.4 V, VOL = 0.4 V Fall Time1 1 dt5 VT = 1.5V Duty Cycle 1 VT = 1.5V tj1s5 Jitter, One Sigma tjcyc_cyc2B VT = 1.5V Jitter, Cycle to cycle
1
MIN 2.4
TYP
MAX 0.4 -22
16 1.1 1.28 52 177 4 4 55 0.5 500
45
UNITS V V mA mA ns ns % ns ps
Guaranteed by design, not 100% tested in production.
0451A--01/10/03
13
ICS94236
Shared Pin Operation Input/Output Pins
The I/O pins designated by (input/output) on the ICS94236 serve as dual signal functions to the device. During initial power-up, they act as input pins. The logic level (voltage) that is present on these pins at this time is read and stored into a 5-bit internal data latch. At the end of PowerOn reset, (see AC characteristics for timing values), the device changes the mode of operations for these pins to an output function. In this mode the pins produce the specified buffered clocks to external loads. To program (load) the internal configuration register for these pins, a resistor is connected to either the VDD (logic 1) power supply or the GND (logic 0) voltage potential. A 10 Kilohm (10K) resistor is used to provide both the solid CMOS programming voltage needed during the power-up programming period and to provide an insignificant load on the output clock during the subsequent operating period. Figure 1 shows a means of implementing this function when a switch or 2 pin header is used. With no jumper is installed the pin will be pulled high. With the jumper in place the pin will be pulled low. If programmability is not necessary, than only a single resistor is necessary. The programming resistors should be located close to the series termination resistor to minimize the current loop area. It is more important to locate the series termination resistor close to the driver than the programming resistor.
Programming Header Via to Gnd Device Pad 2K
Via to VDD
8.2K Clock trace to load Series Term. Res.
Fig. 1
0451A--01/10/03
14
ICS94236
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 needs to be synchronized internal to the device prior to powering down the clock synthesizer. Internal clocks are not running after the device is put in power down. When PD# is active low all clocks need to be driven to a low value and held prior to turning off the VCOs and crystal. The power up latency needs to be less than 3 mS. The power down latency should be as short as possible but conforming to the sequence requirements shown below. CPU_STOP# is considered to be a don't care during the power down operations. The REF and 48MHz clocks are expected to be stopped in the LOW state as soon as possible. Due to the state of the internal logic, stopping and holding the REF clock outputs in the LOW state may require more than one clock cycle to complete.
Notes: 1. All timing is referenced to the Internal CPUCLK (defined as inside the ICS94236 device). 2. As shown, the outputs Stop Low on the next falling edge after PD# goes low. 3. PD# is an asynchronous input and metastable conditions may exist. This signal is synchronized inside this part. 4. The shaded sections on the VCO and the Crystal signals indicate an active clock. 5. Diagrams shown with respect to 133MHz. Similar operation when CPU is 100MHz.
0451A--01/10/03
15
ICS94236
CPU_STOP# Timing Diagram
CPU_STOP# is an asychronous input to the clock synthesizer. It is used to turn off the CPU clocks for low power operation. CPU_STOP# is synchronized by the ICS94236. The minimum that the CPU clock is enabled (CPU_STOP# high pulse) is 100 CPU clocks. All other clocks will continue to run while the CPU clocks are disabled. The CPU clocks will always be stopped in a low state and start in such a manner that guarantees the high pulse width is a full pulse. CPU clock on latency is less than 4 CPU clocks and CPU clock off latency is less than 4 CPU clocks.
Notes: 1. All timing is referenced to the internal CPU clock. 2. CPU_STOP# is an asynchronous input and metastable conditions may exist. This signal is synchronized to the CPU clocks inside the ICS94236. 3. All other clocks continue to run undisturbed.
0451A--01/10/03
16
ICS94236
SYMBOL
In Millimeters COMMON DIMENSIONS MIN MAX 2.413 0.203 0.203 2.794 0.406 0.343
In Inches COMMON DIMENSIONS MIN MAX .095 .008 .008 .110 .016 .0135
A A1 b c D E E1 e h L N
0.127 0.254 SEE VARIATIONS 10.033 7.391 0.381 10.668 7.595 0.635
.005 .010 SEE VARIATIONS .395 .291 .015 .420 .299 .025
0.635 BASIC 0.508 1.016 SEE VARIATIONS 0 8
0.025 BASIC .020 .040 SEE VARIATIONS 0 8
VARIATIONS N 48 D mm. MIN 15.748 MAX 16.002 MIN .620
JEDEC MO-118 DOC# 10-0034
D (inch) MAX .630
6/ 1/ 00 REV B
Ordering Information
ICS94236yF-T
Example:
ICS XXXX y F - T
Designation for tape and reel packaging Package Type F = SSOP
Revision Designator (will not correlate with datasheet revision)
Device Type Prefix ICS, AV = Standard Device
0451A--01/10/03
17

▲Up To Search▲

Price & Availability of ICS94236

	To Download ICS94236 Datasheet File
If you can't view the Datasheet, Please click here to try to view without PDF Reader .