MT8940AC Zarlink Semiconductor, MT8940AC Datasheet
MT8940AC
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MT8940AC Summary of contents
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Features • Provides T1 clock at 1.544 MHz locked to input frame pulse • Sources CEPT (30+2) Digital Trunk/ST-BUS clock and timing signals locked to internal or external 8 kHz signal • TTL compatible logic inputs and outputs • Uncommitted ...
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MT8940 ISO-CMOS Pin Description Pin # Name 1 EN Variable clock enable (TTL compatible input) - This input (pulled internally controls the three states of CV (pin 22) under all modes of operation. When HIGH, enables CV ...
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Pin Description (continued) Pin # Name 10 C8Kb Clock 8 kHz- Bidirectional (TTL compatible input and open drain output with 100K internal resistor to V locks during its NORMAL mode. When DPLL # SINGLE CLOCK mode, this pin ...
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MT8940 ISO-CMOS Functional Description The MT8940 is a dual digital phase-locked loop providing the timing and synchronization signals to the interface circuits for T1 and CEPT (30+2) Primary Multiplex Digital Transmission links. As shown in Figure 1, it has two ...
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MHz (C4o and C4b) and the 2.048 MHz (C2o and C2o) clocks, and the 8 kHz Mode of MS0 MS1 operation X 0 NORMAL Provides the T1 (1.544 MHz) clock synchronized to the falling edge of ...
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MT8940 ISO-CMOS F0b will have no bearing on the operation of DPLL #2, unless FREE-RUN mode as selected by MS0 and MS1. In FREE-RUN mode, the input on F0b is treated the same way as the C8Kb ...
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Applications The following figures illustrate how the MT8940 can be used in a minimum component count approach to providing the timing and synchronization signals for the Zarlink T1 and CEPT interfaces, and the ST-BUS. The hardware selectable modes independent control ...
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MT8940 ISO-CMOS Crystal Clock (12.355 MHz ± 100 ppm) MS0 MS1 MS2 MS3 F0i C12i EN CV C8Kb C16i EN C4o EN C2o Crystal Clock SS (16.388 MHz ± 32 ppm) Figure 5 - Synchronization at the ...
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MT8940 MS0 MS1 MS2 MS3 F0i C12i EN CV C8Kb Crystal Clock C16i (16.388 MHz ± 32 ppm) EN C4o EN C2o Figure 7 - Synchronization at the Slave End of the CEPT Digital Transmission Link ...
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MT8940 ISO-CMOS Absolute Maximum Ratings* Parameter 1 Supply Voltage 2 Voltage on any pin 3 Input/Output Diode Current 4 Output Source or Sink Current 5 DC Supply or Ground Current 6 Storage Temperature 7 Package Power Dissipation * Exceeding these ...
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AC Electrical Characteristics Characteristics 1 Frame pulse input (F0i) to CVb output (1.544 MHz) delay 2 CVb output (1.544 MHz) rise time 3 CVb output (1.544 MHz) fall D time P 4 CVb output (1.544 MHz) clock L period L ...
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MT8940 ISO-CMOS V IH CVb C8Kb F0b FPL V OH C4b C4o 42LH t 42HL V ...
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AC Electrical Characteristics Characteristics 1 C4b output delay (HIGH to LOW) from C8Kb input/output 2 C4b output clock period 3 C4b output clock width (HIGH) 4 C4b output clock width (LOW) 5 C4b output clock rise time 6 C4b clock ...
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MT8940 ISO-CMOS C8Kb Output V OL C8Kb Input C4b FPL V OH F0b V OL Figure 12 - ST-BUS Timings from DPLL #2 and C8Kb Input/Output AC ...
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AC Electrical Characteristics Characteristics 1 Master clocks input rise time 2 Master clocks input fall time C 3 Master clock period L (12.355MHz Master clock period C (16.388MHz Duty Cycle of master clocks 6 Lock-in ...
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MT8940 ISO-CMOS AC Electrical Characteristics Characteristics 1 Delay from Enable to Output (HIGH to THREE STATE Delay from Enable to Output U (LOW to THREE STATE Delay from Enable to Output U (THREE STATE to ...
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MT8940 ISO-CMOS From From Test output output point under test under test C =50pF L Test load circuit =1kΩ L From Test output point under test C =50pF L Test load circuit- 2 Figure 17 ...
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