{"product_id":"cjmcu-5351-si5351a-clock-generator-i2c-8khz-160mhz-arduino-sdr","title":"CJMCU-5351 Si5351A Clock Generator Module — I2C, 8kHz–160MHz for Arduino \u0026 SDR","description":"\u003ch2\u003eCJMCU-5351 Si5351A Clock Generator Module — I2C, 8kHz–160MHz\u003c\/h2\u003e\n\u003cp\u003eThe \u003cstrong\u003eCJMCU-5351\u003c\/strong\u003e breakout module is built around Silicon Labs’ \u003cstrong\u003eSi5351A\u003c\/strong\u003e programmable any-frequency clock generator IC. It provides \u003cstrong\u003ethree independent, phase-coherent clock outputs\u003c\/strong\u003e from 8kHz to 160MHz, all configurable via I2C from an Arduino, Raspberry Pi, or any microcontroller. With a 25MHz TCXO reference and fractional-N PLL synthesis, it generates precise, stable frequencies for software-defined radio (SDR) VFOs, signal generators, frequency counters, and clock distribution applications.\u003c\/p\u003e\n\n\u003ch2\u003eKey Specifications\u003c\/h2\u003e\n\u003ctable\u003e\n  \u003ctr\u003e\n\u003cth\u003eParameter\u003c\/th\u003e\n\u003cth\u003eValue\u003c\/th\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eIC\u003c\/td\u003e\n\u003ctd\u003eSilicon Labs Si5351A\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eOutput Channels\u003c\/td\u003e\n\u003ctd\u003e3 independent clock outputs (CLK0, CLK1, CLK2)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eFrequency Range\u003c\/td\u003e\n\u003ctd\u003e8kHz – 160MHz per output\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eFrequency Resolution\u003c\/td\u003e\n\u003ctd\u003eSub-Hz (fractional-N PLL)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eInterface\u003c\/td\u003e\n\u003ctd\u003eI2C (address 0x60)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eSupply Voltage\u003c\/td\u003e\n\u003ctd\u003e3.3V \/ 5V compatible (onboard regulator)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eOutput Level\u003c\/td\u003e\n\u003ctd\u003e3.3V CMOS square wave\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003ePhase Coherence\u003c\/td\u003e\n\u003ctd\u003eYes — outputs share PLL reference\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eReference Crystal\u003c\/td\u003e\n\u003ctd\u003e25MHz (onboard)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003ctr\u003e\n\u003ctd\u003eOrigin\u003c\/td\u003e\n\u003ctd\u003eCN\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\n\u003ch2\u003eWhy Choose the Si5351A?\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003e3 independent outputs\u003c\/strong\u003e — Generate three different frequencies simultaneously; ideal for IQ signal generation (90° phase offset) in SDR applications\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSub-Hz resolution\u003c\/strong\u003e — Fractional-N PLL synthesis allows extremely fine frequency steps across the full 8kHz–160MHz range\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eI2C control\u003c\/strong\u003e — Simple 2-wire interface; no SPI bus conflicts; works with any I2C-capable microcontroller\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eWide library support\u003c\/strong\u003e — Adafruit Si5351 Arduino library provides easy frequency setting, phase control, and output enable\/disable\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePhase-coherent outputs\u003c\/strong\u003e — All outputs derived from the same PLL reference; enables quadrature (I\/Q) signal generation for direct-conversion SDR receivers\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eTypical Applications\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003eSoftware-defined radio (SDR) VFO and local oscillator\u003c\/li\u003e\n  \u003cli\u003eArduino \/ Raspberry Pi signal generator (audio to HF range)\u003c\/li\u003e\n  \u003cli\u003eFrequency counter reference clock\u003c\/li\u003e\n  \u003cli\u003eQRP amateur radio transceiver VFO\u003c\/li\u003e\n  \u003cli\u003eClock distribution for multiple MCU or FPGA modules\u003c\/li\u003e\n  \u003cli\u003eQuadrature (I\/Q) signal source for direct-conversion receivers\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003ch3\u003eQ: Can the Si5351A output above 160MHz?\u003c\/h3\u003e\n\u003cp\u003eThe Si5351A is specified to 160MHz. Some units may operate up to 200MHz with reduced output amplitude, but this is outside the guaranteed specification. For frequencies above 160MHz, consider the Si5351C or a dedicated VCO module.\u003c\/p\u003e\n\n\u003ch3\u003eQ: What Arduino library should I use?\u003c\/h3\u003e\n\u003cp\u003eUse the \u003cstrong\u003eAdafruit Si5351\u003c\/strong\u003e library (available in the Arduino Library Manager). It supports frequency setting on all three outputs, phase offset control, and output enable\/disable. For advanced PLL configuration, refer to the Silicon Labs Si5351A datasheet and AN619 application note.\u003c\/p\u003e\n\n\u003ch2\u003ePackage Contents\u003c\/h2\u003e\n\u003cul\u003e\n  \u003cli\u003e1× CJMCU-5351 Si5351A Clock Generator Breakout Module\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Keszoox","offers":[{"title":"Orange","offer_id":46985544007915,"sku":"14:350852","price":12.96,"currency_code":"USD","in_stock":true},{"title":"Red","offer_id":46985544040683,"sku":"14:10","price":12.32,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/1005\/8731\/files\/cjmc-5351-clock-generator-module.webp?v=1761198687","url":"https:\/\/keszoox.com\/products\/cjmcu-5351-si5351a-clock-generator-i2c-8khz-160mhz-arduino-sdr","provider":"Keszoox","version":"1.0","type":"link"}