SI5351A-B12005-GTR

The Skyworks Solutions SI5351A-B12005-GTR is a highly integrated, programmable clock generator designed for precision frequency synthesis in communication systems, embedded devices, and test equipment. This device enables multiple, independent, low-jitter clock outputs derived from a single crystal reference or external clock source. The SI5351A-B12005-GTR is optimized for applications requiring flexible frequency generation, stable phase relationships, and low phase noise, making it ideal for microcontrollers, FPGAs, and RF transceiver systems.

## General Features

The SI5351A-B12005-GTR integrates three independent phase-locked loops (PLLs) and eight output drivers, which can be configured as either clock outputs or as disabled channels to save power. It supports both CMOS and clock output levels compatible with I2C control, providing flexible interfacing with modern digital systems. The device operates from a 3.3 V supply and is packaged in a 20-pin TQFN package suitable for compact, high-density PCB designs. The programmable architecture allows dynamic adjustment of output frequencies without hardware changes, facilitating rapid system prototyping and multi-standard support.

## Electrical Specifications

* Supply Voltage (VDD): 3.3 V ±10%
* Supply Current: 80 mA maximum at full load with all outputs enabled
* Output Voltage Levels: CMOS compatible (3.3 V)
* Frequency Output Range: 2.5 kHz to 200 MHz per output
* Reference Input Frequency: 10 kHz to 27 MHz crystal or external clock
* Output Enable/Disable Control: I2C programmable
* RMS Phase Jitter: < 1 ps typical (12 kHz–20 MHz)
* Output Impedance: 25 Ω typical
* Operating Temperature Range: –40 °C to +85 °C
* Package: 20-pin TQFN, 4 mm × 4 mm × 0.9 mm

## Performance and Timing

* Three independent PLLs allow multiple output clocks to maintain fixed or fractional frequency ratios
* Fine resolution frequency synthesis using fractional-N PLL architecture for low phase error
* Low additive phase noise ensures high-quality clock signals suitable for sensitive RF and digital applications
* Fast lock times for PLLs allow quick frequency changes and rapid system initialization
* Programmable output dividers enable frequency scaling across all eight outputs independently

## Protection and Reliability

* Robust operation over industrial temperature range
* ESD protection on all pins rated at 2 kV (HBM)
* Internal thermal protection mechanisms reduce the risk of device failure during abnormal operating conditions
* Stable operation across voltage variations and supply transients, ensuring reliable frequency output
* Long-term reliability in both portable and stationary system designs

## Typical Applications

* Clock generation for microcontrollers, DSPs, and FPGAs requiring multiple synchronized clocks
* RF and communication systems including transceivers, base stations, and wireless infrastructure
* Test and measurement equipment requiring low-jitter, multi-frequency clock sources
* Display and video systems needing precise timing for LCD, LED, and other high-speed interfaces
* Embedded systems requiring flexible clocking for multi-protocol or multi-standard designs

## Key Advantages

* Multiple independent PLLs provide simultaneous output frequencies with fixed or programmable ratios
* Low phase noise and low jitter support high-performance analog and digital systems
* Flexible I2C control enables dynamic frequency changes without hardware modification
* Compact TQFN package allows integration into space-constrained designs
* Wide input reference frequency and output frequency range support diverse applications

## Design Considerations

* Proper decoupling of the supply voltage is recommended to minimize noise and maintain clock signal integrity
* A high-quality reference crystal or external clock improves phase noise and stability
* Routing of clock outputs should minimize trace length and impedance discontinuities to prevent reflections
* Use of termination resistors may be necessary for high-speed or long trace lengths to maintain signal fidelity
* Careful programming of PLL multipliers and dividers is required to ensure the output frequency meets jitter and phase requirements

## Summary

The Skyworks Solutions SI5351A-B12005-GTR is a versatile, low-jitter, programmable clock generator designed for applications demanding multiple, precise clock outputs. Its three independent PLLs, low additive phase noise, and I2C programmability make it ideal for embedded systems, communication equipment, RF transceivers, and high-performance test instruments. With a compact 20-pin TQFN package, wide operating range, and flexible output configuration, it enables reliable and efficient clock management in both industrial and portable designs.