MT8940AC Mitel, MT8940AC Datasheet
MT8940AC
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MT8940AC Summary of contents
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... The timing signals for the CEPT transmission link and the ST-BUS are provided by the second PLL locked to an internal or an external 8 kHz frame pulse signal. The MT8940 is fabricated in MITEL’s ISO-CMOS technology. 2:1 MUX Input ...
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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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... DPLL #2 provides the CEPT PCM 30 timing, and the ST-BUS clock and framing signals. In NORMAL mode, DPLL #2 provides the CEPT and ST-BUS compatible timing signals locked to the rising edge of the 8 kHz input signal (C8Kb). These applications involving MITEL’s (T1 interfaces) and ...
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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 (refer to Figure 15). Otherwise, the input on pin 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 ...
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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 Mitel T1 and CEPT interfaces, and the ST-BUS. The hardware selectable modes independent control over each PLL adds flexibility to the interface circuits. It can be easily reconfi ...
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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 Slave End ...
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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 MT8940 ...
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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 AC Electrical Characteristics Characteristics 1 CV/CVb (1.544 MHz) Setup time 2 CV/CVb (1.544 MHz) Hold time † Timing is over recommended temperature & power supply voltages. ‡ Typical figures are and are for design aid ...
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AC Electrical Characteristics Characteristics 1 F0b input pulse width (LOW) 2 C4b input clock period 3 Frame pulse (F0b) setup time 4 Frame pulse (F0b) hold time † Timing is over recommended temperature & power supply voltages ‡ Typical figures ...
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MT8940 ISO-CMOS AC Electrical Characteristics Voltages are with respect to ground (V ) unless otherwise stated. SS Characteristics 1 Propagation delay (LOW to HIGH), input output 2 Propagation delay (HIGH to LOW), input ...