IDT72V8985 Integrated Device Technology, IDT72V8985 Datasheet
IDT72V8985
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IDT72V8985 Summary of contents
Page 1
... Supporting both GCI and ST-BUS internal circuit to automatically identify the polarity and format of the frame synchronization. A functional block diagram of the IDT72V8985 device is shown on page 1. The serial streams operate continuously at 2.048 Mb/s and are arranged in 125µs wide frames each containing 32, 8-bit channels. Eight input (RX0-7) and ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 PIN CONFIGURATION INDEX RX3 7 RX4 8 RX5 9 RX6 10 RX7 F0i 13 C4i PLCC: 0.05in. pitch, 0.65in. x 0.65in (J44-1, order code: J) TOP VIEW Package Type SSOP: 0.025in. pitch, 0.625in. x 0.295in. ...
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... This output is a 2.048 Mb/s line which contains 256 bits per frame. The level of each bit is controlled by the contents of the CCO bit in the Connection Memory HIGH locations. This input (active LOW) puts the IDT72V8985 in its reset state that clears the device internal counters, registers and brings TX0-7 and microport data outputs to a high-impedance state. The time constant for a power up reset circuit must be a minimum of five times the rise time of the power supply ...
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... DELAY THROUGH THE IDT72V8985 The transfer of information from the input serial streams to the output serial streams results in a delay through the device. The delay through the IDT72V8985 device varies according to the mode selected in the V/C bit of the Connection Memory High. VARIABLE DELAY MODE The delay in Variable Delay Mode is dependent only on the combination of source and destination on the input and output streams ...
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... Processor Mode; i.e., the contents of the Connection Memory LOW (CML, see Table 5) are output on the output streams once every frame unless the ODE input pin is LOW bit is HIGH, then the IDT72V8985 behaves as if bits 2 (Channel Source) and 0 (Output Enable) of every Connection Memory High (CMH, see Table 4) locations were set to HIGH, regardless of the actual value ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 Incoming Now Time Slot 28............ Slots For J: DELAY=3 Slots, 32 Slots, 33 Slots, and 34 Slots For G, H, and I: DELAY= 3 slots Incoming Time Slot 28............ Slots For Slot 1 (" ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 Control Register The Control Register is only accessed when A5=0. All other address bits have no effect when A5=0. When A5 =1, only 32 bytes are randomly accessable via A0-A4 at any one instant. Which 32 bytes are accessed is determined by the state of CRb0 -CRb4. ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 TABLE 3 CONTROL REGISTER Bit Name 7 SM (Split Memory) When 1, all subsequent reads are from the Data Memory and writes are to the Connection Memory, except when the Control Register is accessed again. The Memory Select bits need to specify the memory for the operations. ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 ABSOLUTE MAXIMUM RATINGS Symbol Parameter Vcc Symbol Voltage Vi Voltage on Digital Inputs V Voltage on Digital Outputs O I Current at Digital Outputs O T Storage Temperature S P Package Power Dissapation D NOTE: 1. Stresses greater than those listed under ABSOLUTE MAXIMUM RATINGS may cause permanent damage to the device ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 AC ELECTRICAL CHARACTERISTICS ST-BUS TIMING Symbol Parameter t Frame Pulse Width F0iW t Frame Pulse Setup Time F0iS t Frame Pulse Hold Time F0iH t TX delay Active to Active DAA t RX Setup Time STiS t RX Hold Time ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 AC ELECTRICAL CHARACTERISTICS Symbol Parameter t Clock Period C4i tCL, tCH Pulse Width t Frame Width High WFH t Frame Setup F0iS t Frame Hold F0iH t Data Delay/Clock Active to Active DAA t RX Input Setup STiS t RX Input Hold ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 AC ELECTRICAL CHARACTERISTICS SERIAL STREAM TIMING Symbol Characteristics t TX0-7 Delay - Active to High Z TAZ t TX0-7 Delay - High Z to Active TZA t Output Driver Enable Delay OED t CCO Output Delay XCD t Reset to High Z RSZ t High Z to Reset ...
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... IDT72V8985 3.3V Time Slot Interchange Digital Switch 256 x 256 AC ELECTRICAL CHARACTERISTICS MICROPROCESSOR TIMING Symbol Characteristics CS Setup from DS Rising t CSS t R/W Setup from DS Rising RWS t Add Setup from DS Rising ADS CS Hold after DS Falling t CSH t R/W Hold after DS Falling RWH t Add Hold after DS Falling ADH ...
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ORDERING INFORMATION IDT XXXXXX XX Device Type Package DATASHEET DOCUMENT HISTORY 05/24/2000 pgs and 14. 08/21/2000 pgs and 14. 01/24/2001 pgs. 1 and 9. 04/05/2001 pg. 11. 03/10/2003 pg. 13. 05/09/2003 pgs and ...