Overview
The LTC6948IUFD-2#TRPBF is a high-performance, low-noise phase-locked loop (PLL) with a fully integrated voltage-controlled oscillator (VCO) from Analog Devices Inc. This device is designed for applications requiring precise frequency synthesis and low phase noise. It features a reference divider, phase-frequency detector (PFD), ultralow noise charge pump, fractional feedback divider, and VCO output divider. The fractional divider utilizes an advanced 4th order Δ∑ modulator, which ensures exceptionally low spurious levels and wide loop bandwidths, resulting in extremely low integrated phase noise values.
Key Specifications
| Parameter | Value | Units |
|---|---|---|
| Input Frequency Range (REF+) | 10 - 425 | MHz |
| Input Signal Level (Single-Ended) | 0.5 - 2.7 | Vp-p |
| Input Slew Rate | 20 | V/μs |
| Input Duty Cycle | 50 % | |
| VCO Frequency Range | 2.24 - 6.39 | GHz |
| VCO Tuning Sensitivity | 4.0 - 7.2 %Hz/V | |
| Output Frequency Range (O_DIV = 1) | 3.080 - 4.910 | GHz |
| Output Divider Range | 1 - 6 | |
| Output Duty Cycle | 50 % | |
| Output Resistance (Single-Ended) | 100 - 175 | Ω |
| Supply Voltage | 3.15 - 5.25 | V |
| Operating Temperature | -40°C to 105°C | |
| Package Type | 28-lead QFN |
Key Features
- Ultralow noise 0.37GHz to 6.39GHz fractional-N synthesizer with integrated VCO.
- Advanced 4th order Δ∑ modulator for exceptionally low spurious levels and wide loop bandwidths.
- Programmable VCO output divider with a range of 1 through 6.
- Normalized in-band phase noise floor of -226dBc/Hz (typ) and normalized in-band 1/f phase noise of -274dBc/Hz (typ).
- Excellent integer boundary spurious performance.
- Output buffer muting and reference input frequency up to 425MHz.
- Fast frequency switching and support for fracNWizard™ software design tool.
- Operating temperature range of -40°C to 105°C.
Applications
- Wireless base stations (LTE, WiMAX, W-CDMA, PCS).
- Microwave data links.
- Military and secure radio systems.
- Test and measurement equipment.
- RF and microwave applications for frequency synthesis and clock generation.
- Transceivers, radar systems, and satellite communications.
Q & A
- What is the LTC6948IUFD-2#TRPBF?
The LTC6948IUFD-2#TRPBF is a high-performance, low-noise phase-locked loop (PLL) with a fully integrated voltage-controlled oscillator (VCO) from Analog Devices Inc..
- What is the frequency range of the VCO?
The VCO frequency range is from 2.24 GHz to 6.39 GHz.[
- What is the input frequency range for the reference input?
The input frequency range for the reference input is from 10 MHz to 425 MHz.[
- What is the output divider range?
The output divider range is from 1 to 6.[
- What is the operating temperature range of the LTC6948IUFD-2#TRPBF?
The operating temperature range is from -40°C to 105°C.[
- What package type is used for the LTC6948IUFD-2#TRPBF?
The device is packaged in a 28-lead QFN (Quad Flat No-Lead) package.[
- What are some key applications of the LTC6948IUFD-2#TRPBF?
Key applications include wireless base stations, microwave data links, military and secure radio systems, test and measurement equipment, and RF and microwave applications for frequency synthesis and clock generation.[
- How does the fractional divider in the LTC6948IUFD-2#TRPBF contribute to its performance?
The fractional divider uses an advanced 4th order Δ∑ modulator, which provides exceptionally low spurious levels and allows for wide loop bandwidths, resulting in extremely low integrated phase noise values.[
- What is the significance of the fracNWizard™ software design tool for the LTC6948IUFD-2#TRPBF?
The fracNWizard™ software design tool supports fast frequency switching and helps in optimizing the PLL loop parameters for desired performance.[
- How should the PCB layout be designed to optimize the performance of the LTC6948IUFD-2#TRPBF?
The PCB layout should be designed carefully to minimize signal distortion and interference. This includes keeping signal traces short, using ground planes effectively, and ensuring proper thermal management.[
