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Linduino
Features
- Low Noise Integer-N PLL
- 350MHz to 6GHz VCO Input Range
- –226dBc/Hz Normalized In-Band Phase Noise Floor
- –274dBc/Hz Normalized In-Band 1/f Noise
- –157dBc/Hz Wideband Output Phase Noise Floor
- Excellent Spurious Performance
- Output Divider (1 to 6, 50% Duty Cycle)
- Low Noise Reference Buffer
- Output Buffer Muting
- Charge Pump Supply from 3.15V to 5.25V
- Charge Pump Current from 250μA to 11.2mA
- Configurable Status Output
- SPI Compatible Serial Port Control
- PLLWizard Software Design Tool Support
Typical Application
Description
The LTC®6945 is a high performance, low noise, 6GHz phaselocked loop (PLL), including a reference divider, phasefrequency detector (PFD) with phase-lock indicator, charge pump, integer feedback divider and VCO output divider.
The part features a buffered, programmable VCO output divider with a range of 1 through 6. The differential, low noise output buffer has user-programmable output power ranging from –6dBm to 3dBm, and may be muted through either a digital input pin or software.
The low noise reference buffer outputs a typical 0dBm square wave directly into a 50Ω impedance from 10MHz to 250MHz, or may be disabled through software.
The ultralow noise charge pump contains selectable high and low voltage clamps useful for VCO monitoring, and also may be set to provide a V+/2 bias.
All device settings are controlled through a SPI-compatible serial port.
4x5 QFN-28
Package Variations and Pricing
| Part Number | Package | Pins | Temp | Price (1-99) |
Price (1k)* |
|---|---|---|---|---|---|
| LTC6945IUFD#PBF | QFN | 28 | I | $7.07 | $4.95 |
| LTC6945IUFD#TRPBF | QFN | 28 | I | $5.01 | |
| LTC6945IUFD | QFN | 28 | I | $14.14 | $9.90 |
Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC1649A-A | LTC6945 Demo | Ultralow Noise and Spurious 6GHz Integer-N Synthesizer, VCO=902-928Hz, (Req DC590) | $125.00 |
Companion Boards
| Part Number | Description | Price | Documentation |
|---|---|---|---|
| DC2026C | Linduino One Isolated USB Demo Board: An Arduino- and QuikEval-Compatible Code Development Platform | $75.00 | |
| DC2429A | LT3042 PLL/VCO Supply and Reference Board | $150.00 | |
| DC590B | Isolated USB Serial Controller for Linear Technology QuikEval-Compatible Demo Boards | $50.00 |