DP8473N NSC [National Semiconductor], DP8473N Datasheet
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DP8473N
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DP8473N Summary of contents
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... Implied seek up to 4000 tracks IBM or ISO formatting Low power CMOS with power down mode Y (Continued 9384 – 1 See NS Package Number N48A July 1990 PCAT and most PS 2 Logic Dual-In-Line Package TL F 9384 – 2 Top View Order Number DP8473N RRD-B30M105 Printed ...
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... IBM formats as well as Sony 3 5 (ISO) formats and other enhancements Block Diagram Note 1 The MTR2 MTR3 DR2 and DR3 are not available on the 48 pin DIP (DP8473N J) versions Note 2 See Figure 4 for filter description Note 3 Total transistor count is 29 700 (approx) ...
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Pin Descriptions DP8473 DP8473 Symbol PCC DIP 19–21 17–19 Address lines from the microprocessor This determines which registers the microprocessor is accessing as shown in Table IV in the Register Description Section Don’t care during DMA transfers ...
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Pin Descriptions (Continued) DP8473 DP8473 Symbol PCC DIP MTR0 8 6 This is an active low motor enable line for drive 0 which is controlled by the Drive Control register This is a high drive open drain output MTR1 7 ...
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Typical Application Recommended Plastic Chip Carrier Socket AMP P N 821551-1 or equivalent FIGURE 2 DP8473 Typical Application Functional Description This section describes the basic architectural features of the DP8473 and many of the enhancements provided Re- fer to Figure ...
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Functional Description (Continued) FIGURE 3 Block Diagram of DP8473’s Data Separator TL F 9384– Single Data Rate Note For all filter configurations 250kb s and 300 kb s share the same filter FIGURE 4 Typical Configuration for Loop ...
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Functional Description (Continued) the IBM standard MFM data rates To provide both FM and MFM filters external logic may be necessary The controller takes best advantage of the internal data separator by implementing a sophisticated ID search algo- rithm This ...
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Functional Description (Continued) C Filter capacitor in series with R With pump current 2 2 this determines loop bandwidth R Filter resistor Determines the PLL damping factor 2 C This filter capacitor improves the performance of the 1 PLL by ...
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Functional Description (Continued) Data Rate Register and Clock Logic This is a two bit register that controls the data rate that the controller uses See Register Description This register feeds logic that se- lects the data rates by programming a ...
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Register Description (Continued) TABLE VI Data Rate and Precompensation Programming Values DRVTYP D1 D0 Pin Normal values when PUMP ...
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Result Phase Status Registers D5 Seek End Seek or Recalibrate Command completed by the Controller (Used during Sense Interrupt com- mand ) D4 Equipment Check After a Recalibrate Command Track 0 signal failed to occur (Used during Sense Inter- rupt ...
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Result Phase Status Registers TABLE VIII Summary of FDC Registers Bits 7 6 Register DCR (W) MTR3 MTR2 Enable Enable MSR (R) Request Data for Direction Master Data 7 Data 6 DRR ( DKR (R) ...
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Processor Software Interface both be set before a byte can be read from the Data Regis- ter during the Result Phase If there is information to be transferred during the Execution Phase there are three methods that can be used ...
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Command Description Table READ DELETED DATA Command Phase MT MFM IPS DR1 DR0 Track Number Drive Head Number Sector Number Number of Bytes per Sector End of Track Sector ...
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Command Description Table SCAN HIGH OR EQUAL Command Phase MT MFM IPS DR1 DR0 Track Number Drive Head Number Sector Number Number of Bytes per Sector End of Track ...
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Command Description READ DATA The Read Data op-code is written to the data register fol- lowed by 8 bytes as specified in the Command Description Table After the last byte is written the controller starts looking for the correct sector ...
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Command Description (Continued) Data Mark is read the sector is read normally If a Regular Data Mark is found and the SK bit is set the sector is not read bit 6 of ST2 (Control Mark) is set and the ...
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Command Description (Continued) Notes FE Data pattern of FE Clock pattern Data pattern of FC Clock pattern Data pattern of FB Clock pattern Data pattern of F8 Clock ...
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Command Description (Continued) SEEK There are two ways to move the disk drive head to the desired track number Method One is to enable the Implied Seek Mode This way each individual Read or Write com- mand will automatically move ...
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Command Description (Continued) SENSE DRIVE STATUS This two byte command obtains the status of a disk drive Status Register 3 is returned in the result phase and con- tains the drive status This command does not generate an interrupt MODE ...
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Absolute Maximum Ratings If Military Aerospace specified devices are required please contact the National Semiconductor Sales Office Distributors for availability and specifications Supply Voltage ( Input Voltage ( Output ...
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Phase Locked Loop Characteristics Symbol Parameter V SETCUR Pin Reference REF Voltage K VCO Gain (Note 5) VCO R Recommended Pump 1 Resistor Range K Charge Pump Up Current P(UP) Gain ( (Note 6) REF P(UP) K Charge ...
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AC Electrical Characteristics MICROPROCESSOR READ TIMING Symbol Parameter t Address Valid prior to Read Strobe AR t Address Hold from Read Strobe RA t Read Strobe Width RR t Read Strobe and Chip Select to Data Valid RD t Address ...
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AC Electrical Characteristics OSC2 CLOCK AND RESET TIMING Symbol Parameter t Clock High Time H t Clock Low Time L t Reset Pulse Width RW DMA TIMING (Note 9) Symbol Parameter t End of DRQ from DAK AQ t DAK ...
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AC Electrical Characteristics DRIVE WRITE TIMING Symbol Parameter t Write Data Pulse Width WD t Head Select Setup to Write Gate Assertion HDS t Head Select Hold from Write Gate HDH Note 11 Whenever WGATE is asserted the WDATA line ...
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AC Test Conditions (Notes 11 12 13) Input Pulse Levels GND to 3V Input Rise and Fall Times Input and Output Reference Levels TRI-STATE Reference Levels Active High Active Low Note 11 C 100 pF includes jig and scope capacitance ...
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... Physical Dimensions inches (millimeters) Plastic Dual-In-Line Package (N) Order Number DP8473N NS Package Number N48A 27 ...
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Physical Dimensions inches (millimeters) (Continued) LIFE SUPPORT POLICY NATIONAL’S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION As used herein 1 ...