Product Summary

The Si5332 is a programmable clock generator that can output up to 12 channels and integrates various functions into a single chip. Skyworks' MultiSynth technology enables highly accurate frequency (division ratio) settings for each output clock channel.

In addition, the clock format (eg LVDS, LVPECL, LVCMOS, etc.) can be selected for each bank. In addition, various functions can be assigned by the external pin Universal Hardware input Pin (HW Input Pin). And with Clock Builder Pro, users can easily configure and adjust these great features for many applications.

How to determine the official model number according to the product characteristics of Si5332

There are two types of model numbers for the Si5332: a blank (unwritten) product, and a custom product with the customer's required specifications (register settings) written in the internal NVM memory.

Also, for each, the built-in frequency divider type (Fractional and Integer / Integer mode only), input type (External Crystal Input / Embedded Crystal), output frequency range (5MHz~333MHz / 5MHz~ 200MHz).

See the table below from the Si5332 datasheet for details.

Features of Si5332

1. 6/8/12ch output (differential) can be combined in one chip
2. High jitter performance performance (e.g. 190fs rms @ 12kHz~20MHz offset, 156.25MHz LVPECL output)
3. MultiSynth technology achieves 0ppm frequency output (input clock frequency accuracy = output clock frequency accuracy [ppm])
Four. Output format and output voltage can be selected for each output bank
Five. Dynamically adjustable frequency and phase for each output channel
6. Supports spread spectrum function to reduce EMI
7. 50MHz crystal oscillator built-in type available
8. Various functions can be assigned by HW Input Pin (Input 1 to 7 pins in the figure below)
9. Equipped with Multi-profile function

MultiSynth technology

Skyworks' original technology, this MultiSynth technology enables high-precision/high-resolution frequency setting. Specifically, it is an excellent technology that allows frequency setting up to the 6th decimal place (1.000000Hz) in the order of 1MHz for the input frequency, and also enables synchronized output at 0ppm with no phase error.

As a general frequency divider characteristic, compared to integer division, jitter performance tends to be worse when dividing by fractional frequency. Doing. The block diagram of MultiSynth is shown below. As an example, jitter performance is reduced to 150fs rms when using MultiSynth. (Click here for frequency conditions)

Spread spectrum function

Spread spectrum spreads over a wider band than the frequency band of the original clock signal, and at the same time spreads the energy of the peak portion of the signal to reduce EMI. The spread spectrum function can be easily set by using Clock Builder Pro (CBPro). This is possible by using the MultiSynth divider (N-divider in CBPro) on the Si5332. As an example, you can use the spread spectrum function by assigning an N-divider as shown below.

After completing the spread spectrum function allocation, first select the spreading method from two types of methods: center spread and down spread. Next, select the degree of modulation in the range of 0.1 to 2.5%, select register control or pin control, and the setting is complete.

Types of functions that can be set by HW Input Pins

The Si5332 supports 5/7/7 HW Input Pins for products with 6/8/12 output channels. Also, using Clock Builder Pro, it is possible to assign the following functions to each HW Input pin.

1. SSEN_EN0: Enables spread spectrum, supports MultiSynth0 (N0)
2. SSEN_EN1: MultiSynth1 (N1) capable, enabling spread spectrum
3. FS_INTx: Output side By turning on/off the dividing function of integer, 2 patterns of frequency output can be set.
Four. FS_MSx: Spread spectrum can be set for 2 profiles + 2 patterns of frequency output can be set, or either can be used
Five. OE: Enable/Disable of specified output channel
6. I2C address select: High(1) or Low(0) input to this pin can change the least significant bit of the I2C address
7. CLKIN_SEL[1:0]: Crystal oscillator or input clock can be selected
8. PROFILE_SEL[x]: Input/output/function assignment can be set individually for each profile

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