zl30410 Zarlink Semiconductor, zl30410 Datasheet - Page 13

• Manufacturer Part Number: zl30410
• Description: Multi-service Line Card Pll
• Manufacturer: Zarlink Semiconductor

The ZL30410 provides the following frame pulses (see Figure 15 "ST-BUS and GCI Output Timing" for details). All
frame pulses have the same 125µs period (8kHz frequency):
The combination of two pins, E3DS3/OC3 and E3/DS3, controls the selection of different clock configurations.
When the E3DS3/OC3 pin is high then the C155o (155.52 MHz) clock is disabled and the C34/44 clock is output at
its nominal frequency. The logic level on the E3/DS3 input determines if the output clock on the C34/44 output is
34.368 MHz (E3) or 44.736 MHz (DS3) (see Figure 4, “C34/C44, C155o Clock Generation Options,” on page 13 for
details).
All clocks and frame pulses (except the C155) are output with CMOS logic levels. The C155 clock (155.52 MHz) is
output in a standard LVDS format.
3.4
3.4.1
The ZL30410 supports three Clock Modes: Free-run, Normal (Locked) and Holdover. All Clock Modes are defined
in the international standards e.g., G.813, GR-1244-CORE and GR-253-CORE and they are supported by a
corresponding state in the ZL30410 Control State Machine.
3.4.2
The ZL30410 Control State Machine is a combination of many internal states supporting the three mandatory clock
modes: Free-run, Normal and Holdover. A simplified state machine diagram that is shown in Figure 5 includes
these three states which are complemented by two additional states: Reset and Auto Holdover. These two
additional states are critical to the ZL30410 operation under changing external conditions.
- C155
- F0o
- F8o
- F16o
Control State Machine
Clock Modes
ZL30410 State Machine
: 155.52 MHz clock with nominal 50% duty cycle.
: 244 ns wide, logic low frame pulse
: 122 ns wide, logic high frame pulse
: 61 ns wide, logic low frame pulse
Figure 4 - C34/C44, C155o Clock Generation Options
0
1
11.184
C34/44 Output
8.592
E3DS3/OC3
0
44.736
34.368
1
Zarlink Semiconductor Inc.
ZL30410
13
155.52
active
C155 Output
E3DS3/OC3
0
disabled
1
Data Sheet