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Manufacturer Part #


SX Series 3.3V 1.2 to 1.4 GHz PLL Frequency Synthesizer w/Integrated VCO MLPQ-16

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Mfr. Name: Semtech
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Product Specification Section
Technical Attributes
Attributes Table
Frequency Range: 1.2GHz to 1.4GHz
Supply Current: 0.015mA
Supply Voltage: 3.3V
Phase Noise: -85dBc/Hz
Package Style:  MLPQ-16
Mounting Method: Surface Mount
Features & Applications

Semtech Corporation is a leading supplier of high-quality analog and mixed-signal semiconductor products.  The company is dedicated to providing customers with proprietary solutions and breakthrough technology in power management, protection, advanced communications, human interface, test & measurement, as well as wireless and sensing products.  The Company's integrated circuits (ICs) are employed in communications, computer and computer-peripheral, automated test equipment, industrial and other commercial applications.

SX1781 is a high-performance integer-N frequency synthesizer with built-in phase lock loop (PLL) circuits, including a voltage controlled oscillator (VCO) and loop filter. The SX1781 can generate a frequency output range of 1.2 GHz to 1.4 GHz with an ultra low phase noise characteristics and a very fast settling time. Additionally, the output power level of the device can be programmed to as high as +5dBm.

The chip contributes to environmentally friendly designs with one of the industry’s lowest power consumption levels and with an ultra low power sleep mode for low leakage. The small footprint of the SX1781 represents 36% in board real estate reduction when compared to competitive alternatives, and even more when used to replace a discrete PLL design. The part is RoHS & WEEE compliant, which contributes to hazardous waste reduction.


  • Frequency range:1200 to 1400 MHz
  • Frequency step: 250 kHz min.
  • Phase noise: -85 dBc/Hz @ 10 kHz offset
  • Reference spurs: -67 dBc
  • Hopping time: 350 ms max.
  • Operating voltage: 3.0 - 3.6V
  • Programmable Output Power: up to +5 dBm
  • Integrated VCO and loop filter
  • SPI-bus interface
  • Lock Detect output and squelch
  • Ultra-low power sleep mode
  • Complementary RF outputs
  • Temperature range: -40 to +85°C
  • 4 x 4 mm MLPQ16 package
  • Pb-free and RoHS compliant


  • Wireless Communications Applications
  • Wireless Industrial Applications
  • Automatic Meter Reading
  • Good replacement for discrete PLL Designs


SX1781IMLTRT: MLPQ16 (4mm x 4mm), Lead-Free and RoHS Compliant, 3000 pcs Tape and Reel
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20 Weeks
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