SI5355 Datasheet, PDF (10/22 Pages) Silicon Laboratories – ANY-FREQUENCY 1–200 MHZ QUAD FREQUENCY 8-OUTPUT CLOCK GENERATOR

Si5355
3.3. Input and Output Frequency Configuration
The Si5355 utilizes a single PLL-based architecture, four independent MultiSynth fractional output dividers, and a
MultiSynth fractional feedback divider such that a single device provides the clock generation capability of 4
independent PLLs. Unlike competitive multi-PLL solutions, the Si5355 can generate four unique non-integer
related output frequencies with 0 ppm frequency error for any combination of output frequencies. In addition, any
combination of output frequencies can be generated from a single reference frequency without having to change
the crystal or reference clock frequency between frequency configurations.
The Si5355 frequency configuration is set when the device configuration is specified using the ClockBuilder web-
based utility available at www.silabs.com/ClockBuilder. Any combination of output frequencies ranging from 1 to
200 MHz can be configured on each of the device outputs. Up to three unique device configurations can be
specified in a single device, enabling the Si5355 to replace 3 different clock generators.
3.4. Multi-Function Control Inputs
The Si5355 supports 5 user-defined input pins (pins 3, 5, 6, 12, 19) that are customizable to support the functions
listed below. The pinout of each device is customized using the ClockBuilder utility. This enables the device to be
custom tailored to a specific application. Each of the different functions is described in Table 8.
Pin Function
OEB_ALL
OEB_A
OEB_B
OEB_C
OEB_D
FS0
FS1
RESET
Table 8. Multi-Function Control Inputs Description
Description
Output Enable All.
All outputs enabled when low.
Output Enable Bank A.
CLK0/1 enabled when low.
Output Enable Bank B.
CLK2/3 enabled when low.
Output Enable Bank C.
CLK4/5 enabled when low.
Output Enable Bank D.
CLK6/7 enabled when low.
Frequency Select.
Selects active device frequency plan from factory-
configured profiles.
Frequency Select.
Selects active device frequency plan from factory-
configured profiles.
Reset.
Device reset required to change FS[1:0] pin setting.
Assignable Pin Name
P1, P2, P3, P4, or P5
P1, P2, P3, P4, or P5
P1, P2, P3, P4, or P5
P1, P2, P3, P4, or P5
P1, P2, P3, P4, or P5
P2
P3
P1, P3, P4, P5
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Rev. 1.1